Which BGA Rework Station to get? Scotle, ACHI, or something else?

[Spork Schivago]

Hello,

I currently own some Weller equipment.  I own a Weller WHA-900 Hot Air Rework Station, a Weller WX2 Digital Soldering Control Unit, the 40 watt micro soldering iron with the stand, the 120 watt soldering iron with the stand and a Weller WHP-3000 600 watt preheater.

I've now found a need for a BGA Rework Station.   I would like something that would last me a long time, something that's of decent build quality, and something that's not overly complicated to use.   I'm sure there's going to be a learning curve using any BGA Rework Station, but I don't want something overly complex.

I've done some research and found three.   I was hoping I could get some suggestions.   I'd like to know if anyone has used any of these and if they think they're worth the money.   Essentially, which one would be the highest quality and best suite my needs?

The first one is an ACHI IR PRO SC.   It's 680$.   It runs off 240VAC.   I believe it's 2,000 watt for the preheater and around 400 watt for the top IR heater.

The second one is a 2013 Scotle IR Pro SC V5.   It's 1,140.99$.   It runs off 240VAC.   The posts says the bottom heater is IR 2,000 watt and the top heater is dark IR 450 watt.

The third one is the Scotle HR-460C.   It's used but goes for around 1,500$.   This is the one I think I like the most.   It runs off 240VAC, it has a 7" touch screen, a CCD camera and an LCD screen for the camera.   It has three temperature zones,  MCGS system, Programmable PLC controller and an LED light.   What kind of worries me a bit is the bottom part of the unit.   It has the pre-heater but it also has some IR heater for the BGA component.   So the bottom of the board gets extra heat where the BGA component is and so does the top.   I've included a picture of the actual unit: http://www.scotle.com//scotle-hr460c-bga-rework-machine_l384_p147.html

I like how the HR-460C has the nozzles, so I can try to control the heat a bit more.   I can direct it to just one main area, which I think would be nice.   The bottom heater worries me though.   I'm hoping I can turn it off if I need to.

Does anyone have any experience with any of these, especially the Scotle HR-460C?   I like the camera idea so I can watch the solder melt and do a visual inspection.  I have bad eye sight so that could really come in handy.   I can even use the camera for my Weller hot air rework stuff.    I also like the touch screen part.

I would be using whatever BGA Rework Station I buy to replace BGA components on motherboards.   For example, maybe I'd replace the northbridge on an older Asus board, or a broken socket 775 component.   I'd replace GPUs on laptops.   I'm sure I'd even work on some Xbox 360's, PS3's, and other game consoles.   I'd like something that will last me a long time.

If anyone thinks all of these are a waste of money, maybe they could suggest something a bit better, that doesn't cost 30,000$ or so!   Any help would be greatly appreciated.

Thank you.

[John_ITIC]

I have one of these and I'm very happy with it. Easy to use, never overheats the board etc. I have used it for up to 896 ball BGAs. They are occasionally available on Ebay.
http://www.zeph.com/zt-7.htm

[Spork Schivago]

I have one of these and I'm very happy with it. Easy to use, never overheats the board etc. I have used it for up to 896 ball BGAs. They are occasionally available on Ebay.
http://www.zeph.com/zt-7.htm

John,

Thank you for sharing your knowledge with me.   I looked into those a very long time ago.  They're very very expensive, aren't they?   When I looked into them, NASA used them.   From what I remember reading, they're supposed to be really really good.    How much did it cost you, if you don't mind me asking?   I forgot all about those guys.

[Spork Schivago]

I think I found one, a ZT-7 BGA SMT Reflow System plus the ZT-1-BGS Big Grid AirBath Pre-Heater for 1,499.00$ + 70$ shipping.   It's used.

What size boards can I use with that?   It looks kind of small.    And can I setup profiles with it?   Can I connect it to a PC?   Finally, do I need different nozzles for different components?   I'm sorry for all the questions!   It's just a lot of money for me.   It took my wife and me a very long time to save up for this and we want to make sure we get the right one.   It's definitely an investment and I hope we can make our money back and then some.

Thank you!

[helius]

Hi, you can read all about the ZT-7 at http://www.zeph.com/zt-7.htm
That's a good used price, that combination list price is about $4400. I highly recommend to have an inspection period.
According to the vendor, you can store 31 custom profiles. Those are profiles for the top-side unit; the bottom-side preheater ZT-1-BGS has a fixed heating/cooling profile (2–4 deg C /s preheat phase, and cooling phase using ambient air at whatever rate). There is no PC connection, you enter profiles using the built-in PID controller. You should be able to rework boards that are 21"x21", as long as you have a large enough holder. There are nozzles for specific size components.

The ZT-7 doesn't use a camera, instead it relies on repeatable alignment of the Y-axis and Z-axis bearings so that you can align it on the stencil and then place the chip in exactly the same spot.

[Spork Schivago]

Hi, you can read all about the ZT-7 at http://www.zeph.com/zt-7.htm
That's a good used price, that combination list price is about $4400. I highly recommend to have an inspection period.
According to the vendor, you can store 31 custom profiles. Those are profiles for the top-side unit; the bottom-side preheater ZT-1-BGS has a fixed heating/cooling profile (2–4 deg C /s preheat phase, and cooling phase using ambient air at whatever rate). There is no PC connection, you enter profiles using the built-in PID controller. You should be able to rework boards that are 21"x21", as long as you have a large enough holder. There are nozzles for specific size components.

The ZT-7 doesn't use a camera, instead it relies on repeatable alignment of the Y-axis and Z-axis bearings so that you can align it on the stencil and then place the chip in exactly the same spot.

Thank you.   Could you go a bit more in detail about the repeatable alignment process?   I don't fully understand what you mean by that.

My understand of how to replace a BGA component was this.   You use hot air or IR to remove the component and then you clean the board.   I either clean the chip or replace it.   If I clean it, once done, I put flux on it then I put the chip into something called a jig.   I take a stencil and put that in the other part of the jig.   I put the jig together and pour solder balls onto it.   Once I get all the balls into the holes, then I remove the top part of the jig.   At this point in time, I was told I should use my Weller WHA-900 hot air rework station to melt those balls.    Then I align the chip onto the board and use the BGA rework station.

Is the procedure I described incorrect?   I'm going to see if I can find a youtube video of someone replacing a BGA component with the ZT-7 to get an idea.

Also, while looking around on the net, I found this post:

a hot air setup wont be sufficient to reflow a ps3's cpu or gpu - you'll need an IR reflow machine to do it properly. there's a secondary heat transfer metal glued to the top of the chip that disrupts the hot air process, making the heating of the bga balls inaccurate. raising the hot air temp will only force the solder out the side ruining the job. IR penetrates, hot air envelopes. a hot air setup would be perfect for a 360 though....

I know what metal part on the GPU's / CPU's they're talking about on the PS3's.   But is this true?   Would I have a much less success rate repairing Playstation 3's using hot air instead of infrared?   I trust the responses here much more than the posts on psx-scene.com, when it comes to stuff like this, so that's why I'm asking here.   Thank you!

[Spork Schivago]

Also, I want to make sure I understand this correctly,

each nozzle is 299$ and each stencil is 349$?   I found that here:  http://www.zeph.com/nozzles_bga.htm

That claims it's for the ZT-7.   If I need different nozzles for different BGA components, I don't think I could even afford one of those nozzles!   I mean if it was something like 299$ includes all the nozzles they got listed, I could probably do that.   But 299$ per nozzle?   That's crazy!!!

[helius]

Thank you.   Could you go a bit more in detail about the repeatable alignment process?   I don't fully understand what you mean by that.

The ZT-7 has a gantry that moves only in the Y-axis (toward or away from you). It doesn't move along the X-axis (left to right). So as long as your board stays stationary, the location of the nozzle is always the same along the X-axis.
The head moves vertically as well (the Z-axis). When you are ready to place a chip, you put the nozzle down on the board and position it so it lines up exactly with the silkscreen outline, which is generally present for BGAs because it helps placement. If a board was designed without any outline, then aligning the nozzle may require a "template" which is just an alignment aid that is the same outline as the outer pads. Then move the head up the Z-axis, and put the chip into the nozzle (it is held with suction). When you move the head down it will still be in alignment.

My understand of how to replace a BGA component was this.   You use hot air or IR to remove the component and then you clean the board.

The ZT-7 automatically removes the chip from the board when it reaches liquidus. The suction in the nozzle is turned on after it's positioned on the chip to be removed, and automatically lifts the chip off of the board. You can then release the suction to recover the chip, and replace it without moving the machine, so the new chip is exactly where the old one was.

If I clean it, once done, I put flux on it then I put the chip into something called a jig.   I take a stencil and put that in the other part of the jig.   I put the jig together and pour solder balls onto it.   Once I get all the balls into the holes, then I remove the top part of the jig.

All those steps are part of the reballing process, which as you've said, requires special jigs. Zephyrtronics has its own kit for this that uses the nozzle of the ZT-7 to heat the jig so that the balls melt and adhere to the component's pads. http://www.zeph.com/reballing_kit.html

I'm going to see if I can find a youtube video of someone replacing a BGA component with the ZT-7 to get an idea.

[Spork Schivago]

So the nozzles that I use would be the exact same size as the component that I'm removing?   I think I understand now.

I found the same video you found!   I really want this ZT-1 with the solder bath, but if those nozzles really are 299$ each and I need one for each different size chip, there's no way I can afford something like that.   I was expecting the nozzles to be around 20$ to 40$ a piece, depending on the size of the BGA component being removed.

[helius]

If I need different nozzles for different BGA components, I don't think I could even afford one of those nozzles!   I mean if it was something like 299$ includes all the nozzles they got listed, I could probably do that.   But 299$ per nozzle?   That's crazy!!!

They have low sales volumes, so margins are high.

IR penetrates, hot air envelopes.

I know what metal part on the GPU's / CPU's they're talking about on the PS3's.   But is this true?

Unless they've discovered some new physical principle, no, it's not true. Only semiconductors like germanium and silicon, and certain types of glass, are transparent to infrared rays.

[John_ITIC]

Note that there are cheaper SMT nozzles, which cost about half as the BGA nozzles. I spoke with Jack at Zephyrtronics who said that the nozzles are actually the same. The SMT nozzles are however smaller and if your BGZA is large you need to buy the larger (and more expensive BGA nozzles). However, there are SMT nozzles with 33mm in square, which covers most mid-size BGAs too.

http://www.zeph.com/nozzles_smt.htm

Regarding temperature profiles: The older ZT-7 models (like mine) does not have a PID controller which controls the temperature accordingly to a proper soak/reflow/cool down temperature profile. The actual profile looks more like a capacitor charging curve but it works well. Accordingly to Jack @Zephyrtronics, a "proper" reflow curve is not needed but since customers asked for it they simply put in another PID controller in the newer units. There is no PC connection but you can replace the PID controller with one that has a PC interface if you feel like it. This is not needed, however, since I just set the air bath temp to 150 degrees C, wait a couple of minutes, set the upper heater to 260 Deg C, wait a couple of minutes and then the job is done. Easy really.

I'm actually using my ZT-7 tonight, reworking a BGA. I think I paid between $1.5K to $2K for mine but it was new on Ebay.

[Spork Schivago]

If I need different nozzles for different BGA components, I don't think I could even afford one of those nozzles!   I mean if it was something like 299$ includes all the nozzles they got listed, I could probably do that.   But 299$ per nozzle?   That's crazy!!!

They have low sales volumes, so margins are high.

IR penetrates, hot air envelopes.

I know what metal part on the GPU's / CPU's they're talking about on the PS3's.   But is this true?

Unless they've discovered some new physical principle, no, it's not true. Only semiconductors like germanium and silicon, and certain types of glass, are transparent to infrared rays.

I thought as much.   I questioned it though because I thought maybe the mini-heatsink, well, acted like a heatsink, but I didn't really see how IR would affect it any different at all.   If anything, I'd probably have to remove the mini-heatsink / shield / whatever it's called whether I use infrared heating or hot air.   Thank you for clarifying this for me!

The sales margin news is terrible news for me.   I really liked the idea of owning one of these.   I was hoping I was misreading the information on the page.

[Spork Schivago]

Note that there are cheaper SMT nozzles, which cost about half as the BGA nozzles. I spoke with Jack at Zephyrtronics who said that the nozzles are actually the same. The SMT nozzles are however smaller and if your BGZA is large you need to buy the larger (and more expensive BGA nozzles). However, there are SMT nozzles with 33mm in square, which covers most mid-size BGAs too.

http://www.zeph.com/nozzles_smt.htm

Regarding temperature profiles: The older ZT-7 models (like mine) does not have a PID controller which controls the temperature accordingly to a proper soak/reflow/cool down temperature profile. The actual profile looks more like a capacitor charging curve but it works well. Accordingly to Jack @Zephyrtronics, a "proper" reflow curve is not needed but since customers asked for it they simply put in another PID controller in the newer units. There is no PC connection but you can replace the PID controller with one that has a PC interface if you feel like it. This is not needed, however, since I just set the air bath temp to 150 degrees C, wait a couple of minutes, set the upper heater to 260 Deg C, wait a couple of minutes and then the job is done. Easy really.

I'm actually using my ZT-7 tonight, reworking a BGA. I think I paid between $1.5K to $2K for mine but it was new on Ebay.

Okay, you got me thinking maybe this ZT-7 is a good buy again.   With those nozzles, how many do you actually own?   I counted about 30 nozzles for the BGA stuff.   The SMT one lists the 13 most common ones.   Even at 150$ though, 13 is close to 2,000$.   Maybe I should just go back to one of the IR units, like the Scotle.

If I understand everything, every hot air unit will require a nozzle, but any IR unit won't.   So that one IR unit that I liked, the one with the CCD camera (which seems like it might be more of a luxury than anything else really), I believe it's a hybrid.  Only IR for the preheater, the rest is hot air.   So I'd need nozzles for that unit as well.

This is going to be a lot more expensive then I thought it'd be.   I figured I'd need to buy some jigs and stencils, some solder balls and flux, my BGA machine and be on my way.

[John_ITIC]

Only buy the nozzles when you need them. For my small PCBs, I only have two BGAs so two sizes. I've only bought one from Zephyrtronics since I actually got some 5-6 nozzles with my ZT-7 on Ebay. I have duplicates I can sell you if you need: two 27x27, model 3006.

[Spork Schivago]

Only buy the nozzles when you need them. For my small PCBs, I only have two BGAs so two sizes. I've only bought one from Zephyrtronics since I actually got some 5-6 nozzles with my ZT-7 on Ebay. I have duplicates I can sell you if you need: two 27x27, model 3006.

You would do that?   Wow, thank you so much!   How much would one cost me?   I wanted to try repairing a few PS3's and 360's I have here.   I wonder what size they'd need.   I also have a bunch of motherboards (mainly laptops) I'd like to work on.  I'm pretty sure most of the ones that won't POST are just the GPU.   They'd also make great test boards because they're older.   There's also an older Asus socket 775 board I want to replace the socket on.   That means a little bit to me though so I don't want to ruin that.

I'd only need one 27x27, right?  There wouldn't ever be a need for me to own a second one unless I bought another Zyph unit for someone else to use or my first nozzle broke.   I wouldn't think that'd happen very much.


Someone mentioned that I could purchase a PID controller with a PC connection so I could hook it up to the PC if I wanted too.   I almost have half the mind to guy my Weller WHA-900 Hot Air machine and try controlling it via the PC with one of those PID controller things.   I lack the knowledge right now.   I started getting into learning how to make PCBs but got side tracked.   I know a little bit not enough I don't think.   The main problem would be the preheater.   My WHA-3000 isn't powerful enough for most boards, like a PS3 or laptop board.   Buying the heating elements wouldn't be a problem, and although I have a PIC programmer, I don't think I'd be able to make the circuit board to control the heating elements.

Eventually, I'd like to make my own BGA rework station, that's way down the road though.

[blacksheeplogic]

I currently own some Weller equipment.  I own a Weller WHA-900 Hot Air Rework Station, a Weller WX2 Digital Soldering Control Unit, the 40 watt micro soldering iron with the stand, the 120 watt soldering iron with the stand and a Weller WHP-3000 600 watt preheater.

As you own both the WHP-3000 preheater + board holder, and the WHA-900 have you considered adding the arm which directly attaches the board holder and will work with the WHA-900. The arm allows you to clip the hot air hand piece to it and provides the ability to raise and lower the arm. It's a completely manual system but quite capable depending on your needs. Weller has a video featuring it with the WHA-3000P but that uses the same hand piece.

[Spork Schivago]

I currently own some Weller equipment.  I own a Weller WHA-900 Hot Air Rework Station, a Weller WX2 Digital Soldering Control Unit, the 40 watt micro soldering iron with the stand, the 120 watt soldering iron with the stand and a Weller WHP-3000 600 watt preheater.

As you own both the WHP-3000 preheater + board holder, and the WHA-900 have you considered adding the arm which directly attaches the board holder and will work with the WHA-900. The arm allows you to clip the hot air hand piece to it and provides the ability to raise and lower the arm. It's a completely manual system but quite capable depending on your needs. Weller has a video featuring it with the WHA-3000P but that uses the same hand piece.

Blacksheeplogic,

I'm sorry if I misled you somehow, but I do not own the board holder.   I bought the preheater separate from the WHA-900.   The board holder was another 1,800$ or so, so I passed on it.   If I did have the board holder and a bigger pre-heater, I'd still need a way to do profiles.   From what I've read, without profiles, the rework just won't hold.

I originally wanted to do something similar to your idea.   Find a way to control the hot air from a PC, so I could essentially use profiles.   Right now, the WHA-900 has pots that I turn to manually adjust the temp and airflow.   I thought maybe the PID controller would somehow allow me to control the temp digitally.   I know the language that the preheater speaks.   Weller was kind enough to share the RS232 protocol information with me, so I could write my own program to control that, if need be.   But 600 watt for a preheater just isn't enough, from what people have told me.   If I had the 2,000 watt one, I'd be good.

I went to some BGA Mod website and asked for any how-to's on a professional grade ~2,000 watt preheater but never got a response.   Weller does make a 2,000 watt version of the preheater I have but it's expensive.   I thought maybe I could some how modify my unit, add a couple heating elements and have a nice 2,000 watt preheater.

I would have so much fun and learn so much making my own using the stuff I have but because I lack the technical know how, my biggest fear is I'd mess it up to the point where it wouldn't work and I'd lose all my equipment.   I love the design of the Weller PCB holder, I've seen pics on-line.   If I could snag one of those for fairly cheap, then I think I'd just need to get a bigger preheater and then find a way to control my WHA-900 digitally, then I'd be all set.

[blacksheeplogic]

But 600 watt for a preheater just isn't enough, from what people have told me.

It's plenty big enough as long as it accommodates the area being reworked. The final ramp is done by the hot air.

From what I've read, without profiles, the rework just won't hold.

You have been mis-informed. It's nice to be automated and you do't have to pay as much attention to the process, but it's not true it can't be done manually. Plenty of manual system out there that work. Plenty of people making do with just what they have as well.

From what I've read, without profiles, the rework just won't hold.

Yes, you need to learn and make adjustments to match your system, and the boards. But automation is just connivence and an increase in your time efficiency. How many boards are you going to be doing in the next year?

If I had the 2,000 watt one, I'd be good.

No, your still going to have to learn and adjust to your boards & equipment. Use what you have and you will be much better off. Your boards dictates what size preheater. Your in business, the workload has to justify the investment as well as what you need to do the work. I doubt the in crease in work will be worth any significant investment. It's a different game if t's just a hobby.

I would have so much fun and learn so much making my own using the stuff I have but because I lack the technical know how, my biggest fear is I'd mess it up to the point where it wouldn't work and I'd lose all my equipment.   I love the design of the Weller PCB holder, I've seen pics on-line.   If I could snag one of those for fairly cheap, then I think I'd just need to get a bigger preheater and then find a way to control my WHA-900 digitally, then I'd be all set.

Unfortunately, there's no system I know of out there that does not require a significant investment in learning.Teach-in helps but ultimately, you need to learn and adapt to the boards you will be working on. Just because someone has a profile that works for them does not mean you will be able to run with that and get the same results.

Use what you have and adapt to a manual process, accept it may not be the most efficient process and use of your time, but if the work justifies then invest. If you can't make what you have work, you won't be able to make a $1,500 rework system work either. Rework systems in that price range simply are not turn on and walk away.

[Spork Schivago]

But 600 watt for a preheater just isn't enough, from what people have told me.

It's plenty big enough as long as it accommodates the area being reworked. The final ramp is done by the hot air.

From what I've read, without profiles, the rework just won't hold.

You have been mis-informed. It's nice to be automated and you do't have to pay as much attention to the process, but it's not true it can't be done manually. Plenty of manual system out there that work. Plenty of people making do with just what they have as well.

From what I've read, without profiles, the rework just won't hold.

Yes, you need to learn and make adjustments to match your system, and the boards. But automation is just connivence and an increase in your time efficiency. How many boards are you going to be doing in the next year?

If I had the 2,000 watt one, I'd be good.

No, your still going to have to learn and adjust to your boards & equipment. Use what you have and you will be much better off. Your boards dictates what size preheater. Your in business, the workload has to justify the investment as well as what you need to do the work. I doubt the in crease in work will be worth any significant investment. It's a different game if t's just a hobby.

I would have so much fun and learn so much making my own using the stuff I have but because I lack the technical know how, my biggest fear is I'd mess it up to the point where it wouldn't work and I'd lose all my equipment.   I love the design of the Weller PCB holder, I've seen pics on-line.   If I could snag one of those for fairly cheap, then I think I'd just need to get a bigger preheater and then find a way to control my WHA-900 digitally, then I'd be all set.

Unfortunately, there's no system I know of out there that does not require a significant investment in learning.Teach-in helps but ultimately, you need to learn and adapt to the boards you will be working on. Just because someone has a profile that works for them does not mean you will be able to run with that and get the same results.

Use what you have and adapt to a manual process, accept it may not be the most efficient process and use of your time, but if the work justifies then invest. If you can't make what you have work, you won't be able to make a $1,500 rework system work either. Rework systems in that price range simply are not turn on and walk away.

I had asked over on badcaps.net and the people who responded said the 600 watt just wasn't large enough for the types of boards I wanted to work on.   It's more than just a hobby.   The making the circuit boards, that's hobby, but the repairs are how I make my money.   If I can replace, let's say, a bad socket on a motherboard, I believe I can make more money than just replacing the motherboard.

So, you're thinking 600 watt pre-heater would be fine?   My original question on BadCaps was could I do BGA equipment by hand with hot air.   I told them I had manual controls and that I would just change the temperature to what the profile for the BGA component says.   The people that responded said no.   Then I thought about adapting my equipment, modifying the WHA-900 to be controlled by the computer, for the temperature profiles.   From everything I've read, profiles are important.   The whole heat it up to x degrees C at 2-3 degrees C ramp temp (or whatever it's called), hold it there for x amount of seconds, increase the temp to x degrees C at 2-3 degrees C ramp temp, hold it there for x amount of seconds, etc.

If I buy or make a BGA Rework Station, I don't think it's going to be as simple as just flipping a switch.   My WHA-900 taught me that when I first bought it!   Way back in the day I thought it'd be nice and easy, but no, it took a good amount of time and dedication to learn how to properly use it.   There's things I still struggle with but I've adapted a bit and learned a lot over the year that I've had it.

I was under the impression that the more, how do I word this, the more equal the air temp on the chip, the better the reflow...for example, if I try holding my hot air wand or whatever you want to call it over the chip and I'm moving it around, that wouldn't be very good.   I'd want it stationary.   Is that wrong as well?   I appreciate you letting me know these things.   People said the 600 watt wouldn't be large enough to heat an entire PS3 board uniformly.   I know the three ceramic heating elements aren't much.   It seems to mainly heat the middle of larger boards.   Would that really matter though?   If not, I'd like to use what I get and just try to adapt it to work.   I do want the profiles though, so I don't have to manually turn knobs all the time.   If I control the temp digitally via a PC or something, I think I'd be good.

[helius]

The point of a pre-heater is to uniformly raise the temperature of the board to a warm, but below liquidus, temperature. The more slowly you can ramp up to that temperature, the safer the board is from microcracks being formed because the temperature will remain even. 150°C is a good starting point, since that is hot enough to activate most fluxes. The goal is not to slam the thing on and have the board zoom up to reflow temperature.
The pre-heater solves two problems: Firstly, since the whole board starts warm, there is less of a thermal disconnect between the reflowed part and the board around it, which reduces stress fracturing. Secondly, since the whole board is warm including ground and power planes, you don't have problems reflowing chips with ground tabs because the rate of heat escaping to the ground plane is lower. The pre-heater is not for heating up the target component itself! You can use the pre-heater for through-hole desoldering too, it solves the same problems there.
You can calculate the pre-heater power needed by using the Boltzmann equation \$P=\epsilon\cdot\sigma\cdot A\cdot \Delta T^4\$. The emissivity \$\epsilon\$ of FR-4 is about 0.9. This is the heat flow by radiation off the warm board that you need to balance with your pre-heater. For a 1 sq meter board this is only about 40 watts, which is confirmed by the pre-heated board feeling as warm as a dim bulb.

[Spork Schivago]

The point of a pre-heater is to uniformly raise the temperature of the board to a warm, but below liquidus, temperature. The more slowly you can ramp up to that temperature, the safer the board is from microcracks being formed because the temperature will remain even. 150°C is a good starting point, since that is hot enough to activate most fluxes. The goal is not to slam the thing on and have the board zoom up to reflow temperature.
The pre-heater solves two problems: Firstly, since the whole board starts warm, there is less of a thermal disconnect between the reflowed part and the board around it, which reduces stress fracturing. Secondly, since the whole board is warm including ground and power planes, you don't have problems reflowing chips with ground tabs because the rate of heat escaping to the ground plane is lower. The pre-heater is not for heating up the target component itself! You can use the pre-heater for through-hole desoldering too, it solves the same problems there.
You can calculate the pre-heater power needed by using the Boltzmann equation \$P=\epsilon\cdot\sigma\cdot A\cdot \Delta T^4\$. The emissivity \$\epsilon\$ of FR-4 is about 0.9. This is the heat flow by radiation off the warm board that you need to balance with your pre-heater. For a 1 sq meter board this is only about 40 watts, which is confirmed by the pre-heated board feeling as warm as a dim bulb.

I knew the purpose of the preheater.   Keep in mind, I've been using my hot air rework station for SMD components that aren't BGA for a while now.   I noticed with smaller boards, the preheater heats the whole board but with the larger ones, (I'll double check later today), I believe the whole board doesn't warm equally.   The center is good, but the outside edges aren't.   This could be do to the fact that I don't have a stand and the boards simply lay on the preheater of mine.

When I was talking about profiles, what I meant was the BGA components.   Everything I've read and talked about say they're required for a proper reflow / rework.   Some places even say the ramp temperature is important as well (how fast the temperature raises).   Some even say the speed at which the unit cools is important as well (if I use a fan to cool it super quick like, it might not hold as well as if I had just let it cool naturally).    Generally, when I replace a SMD IC, I'll preheat the board to around 150C.   Then I'll use my hot air to remove the component.   I'll clean the board.   I'll use my preheater and turn it all the way down.   I'll let the board cool down to the small temp.   With my K-Type thermocouple hooked up, I can see the actual temp of the board (or something very close to it).   I'm not sure that step is neccessary though.

Then I turn off the preheater.   I'll use my soldering iron and desoldering wick to clean the board.   I'll remove neighboring components and use a stencil made for the SMD IC I'm replacing.   If it's something like an SMD capacitor or resistor, I'll just use a toothpick and put a dab of soldering paste on, but for the ICs that have many pins, I'll use the stencil.   I'll use a spreader card to spread the thermal paste on.   I'll remove the stencil, and put the IC on.   Originally, I had trouble lining up the ICs but I learned when I start heating the component, it gets "sucked" into place.   Before I add the head, with the IC on, I'll turn the preheater back on.   The thermal paste gets liquidy, like you or someone else described.

For BGA though, from the questions I have asked on other forums, and from what I've read, there's a few things that determine whether the reflow will hold.   I thought the most important was the profile.   You know, heating it to temperature X, holding the temp there for so many seconds (maybe 180), heating it to temperature Y, holding it there for so many seconds, etc.   Each BGA component is different.

I'm confused by what Blacksheeplogic said though.   I just want clarification, maybe I'm misunderstanding Blacksheeplogic.   Those profiles that I just described, are they not actually needed?   Can I just put the BGA component on and add heat until the balls melt?   If so, I guess I wouldn't even have to modify my WHA-900.   I could use it as it is.   It's just everything I've read and discussed seemed to suggest otherwise.   Maybe I'm misunderstanding what you're saying Blacksheeplogic or maybe I'm using the wrong terminology.   Maybe what I'm describing isn't really called the BGA temperature profile?

I have to make a decision now.   I'm very tempted to purchase the Zyph unit.   I have a bunch of systems that have BGA components that need replacing.   It's a heck of a deal but if my current equipment will do BGA components, I'll just use that.   The only reason I wanted to mod the WHA-900 and hook it up to the PC was to control the temperature.   To increase it slowly, via software and follow those "profiles".   Thanks for taking the time to answer my questions and clarifying all of this for me.   I don't mean to ask so many questions, but I really want to understand this before I make a purchase for hardware I might not need.

[Spork Schivago]

Also, if I understand the literature for my preheater, the WHA-3000, 600 watt one, the maximum size board it can preheat is 4.72" x 7.28" / 120 mm x 185 mm.   That's smaller than the boards I need to work on.

[Spork Schivago]

The Zephyrtronics is gone now.   I waited too long.   

[bson]

Also, if I understand the literature for my preheater, the WHA-3000, 600 watt one, the maximum size board it can preheat is 4.72" x 7.28" / 120 mm x 185 mm.   That's smaller than the boards I need to work on.

If you get a board holder you can place it and preheat only the area you work on.  I'd give that a shot first.  What's the thermal mass of the hot plate?  It might be that just turning it off will provide all the gradual cooling you need.

[Spork Schivago]

Also, if I understand the literature for my preheater, the WHA-3000, 600 watt one, the maximum size board it can preheat is 4.72" x 7.28" / 120 mm x 185 mm.   That's smaller than the boards I need to work on.

If you get a board holder you can place it and preheat only the area you work on.  I'd give that a shot first.  What's the thermal mass of the hot plate?  It might be that just turning it off will provide all the gradual cooling you need.

Thanks, how would I figure out the thermal mass of the pre-heater?   I'm not so much worried about the gradual cooling.   I'm more worried about it just being to small to properly heat the size boards I work on.   For the component I replaced earlier today on a board, the outside edges of the board got a little warm, but the board was definitely not heated equally.

How important is it with BGA rework for the entire board to heat equally?   If I just preheated the area where I'm doing the BGA work instead of the entire board, would it mess things up?   I see a lot of preheaters that have a lot of wattage.   I'd think if something like 600 watts was good enough, I'd see a lot of 600 watt preheaters for BGA rework.   But I keep seeing 2,000 watt, 4,000 watt, etc.

[blacksheeplogic]

How important is it with BGA rework for the entire board to heat equally?   If I just preheated the area where I'm doing the BGA work instead of the entire board, would it mess things up?   I see a lot of preheaters that have a lot of wattage.   I'd think if something like 600 watts was good enough, I'd see a lot of 600 watt preheaters for BGA rework.   But I keep seeing 2,000 watt, 4,000 watt, etc.

If your really concerned about this aspect, you can always warm the board in an oven. However, the information you got regarding "reflowing not taking" due to a small board preheater while probably well meaning posters responded to your query, the only advice I can give you is to research further before investing in gear and taking on work that's going to be a warranty issue for you... Unless you have a source for these chips don't do it. It's just not going to be good for your business.

[Spork Schivago]

How important is it with BGA rework for the entire board to heat equally?   If I just preheated the area where I'm doing the BGA work instead of the entire board, would it mess things up?   I see a lot of preheaters that have a lot of wattage.   I'd think if something like 600 watts was good enough, I'd see a lot of 600 watt preheaters for BGA rework.   But I keep seeing 2,000 watt, 4,000 watt, etc.

If your really concerned about this aspect, you can always warm the board in an oven. However, the information you got regarding "reflowing not taking" due to a small board preheater while probably well meaning posters responded to your query, the only advice I can give you is to research further before investing in gear and taking on work that's going to be a warranty issue for you... Unless you have a source for these chips don't do it. It's just not going to be good for your business.

I think maybe I worded things weirdly.  My pre-heater could be larger.   The specs for it say it's meant for much smaller boards, but what I meant was without the temperature profiles, rework / reballing, from what I've read (and tried) just doesn't seem to work.   I know when I use my smaller preheater on a larger board that what it's rated for, for SMD rework, the board tends to warp a little bit.   Not too much, but I'd think enough where maybe it'd cause issues.   With smaller boards, I don't have any warpage.  If the board warps because I'm not properly preheating it, then when it's being used, it warms up a bit, I feel it could cause issues.   If I'm wrong, please correct me.

Removing a BGA component, reballing it using a stencil, jig and my WHA-900, aligning the BGA component on the board and just using heat to reattach the component never seemed to last more than 3 months or so.  When I asked people about this, they said the profiles in the datasheets are very important to a proper rework.   Just melting the solder isn't enough.  I originally thought I could hook my preheater up to the PC and hook a k-type thermocouple up to the preheater.   Then, I could modify my Weller WHA-900 to control the temperature via the computer.   The computer program I would write would watch the temperature of the BGA component (through the preheater's k-type thermocouple) and adjust the temperature of the Weller WHA-900 accordingly.   I've currently given up on that idea though and just purchased a BGA rework station.   Time, right now, is a bit of an issue and I need to get things moving a bit.

I've now purchased my BGA rework station.   It's a mix between IR and hot air.   I'd like some suggestions on fluxes now.   Does anyone have any suggestions for a good brand of no-clean flux for BGA rework?   I'd prefer something that's lead-free.   I've been using ChipQuik Lead-Free SMD291 Tack Flux N/C.   What do you guys mainly use?   Mine comes in a little syringe but I'd like to get a container where I just brush it on.

Thanks for the help and information guys.  It's much appreciated.

[Deus]

Just popped in, pitty I didn't see this sooner.
Which rework station did you finally get?

Chipquick should be ok, never used it myself, but know some people use(d) it with good success.

Amtech NC559ASM TPF is used by many reballers.
Using it too.

[Spork Schivago]

Just popped in, pitty I didn't see this sooner.
Which rework station did you finally get?

Chipquick should be ok, never used it myself, but know some people use(d) it with good success.

Amtech NC559ASM TPF is used by many reballers.
Using it too.

I ended up going for the Scotle HR-460C.   I'm a bit disappointed in the unit.   I guess it's probably I was just having my standards a bit too high, you know?   I was expecting something a lot nicer.   I've opened up my Weller WHP-3000 before and I think it's professionally done.   It looks real nice, you can tell Weller took their time with it and did a good job.   I open up this Scotle (it got broke during shipping so I have to fix it) and it looks like it was just thrown together.   Like Scotle just used various parts from different sources and maybe didn't even make anything themselves, circuit wise.  One of the IR heating elements is ruined so I have to replace that.   Before I order replacements, I'm waiting for FedEx to get back with us.   They should pay for it because they're the ones who broke it.

I went for the AMTECH LF-4300.   I wanted lead-free.   There seems to be some counterfeit AMTECH stuff floating around on the net.   I contacted the people that make the AMTECH stuff directly and confirmed where I bought from was the real deal.   A lot of the stuff on e-Bay I think might be fake.   I went for a 75 gram jar of the LF-4300.

[Deus]

Can't speak for now, but got my rework machine from Scotle to back in the days, 6-7 years ago?
Got something broken or missing too, can't remember exactly.
After contacting Scottle, they helped me out with it pretty quickly.
Suppose you already did but if not, maybe to contact them too?

About that flux, 4300, water washable?
Make sure to clean all off. If you attach a BGA with it, same, use ultrasonic cleaner with the correct liquid (check amtech) to make sure you get all residue from under the BGA.
All water based stuff is more agressive, even if it says no clean think it would be safest to make sure to get all off.

Seen some nasty pics of damaged solder masks in the past. Sorry, no links anymore that forum it was on is down.

[Spork Schivago]

Can't speak for now, but got my rework machine from Scotle to back in the days, 6-7 years ago?
Got something broken or missing too, can't remember exactly.
After contacting Scottle, they helped me out with it pretty quickly.
Suppose you already did but if not, maybe to contact them too?

About that flux, 4300, water washable?
Make sure to clean all off. If you attach a BGA with it, same, use ultrasonic cleaner with the correct liquid (check amtech) to make sure you get all residue from under the BGA.
All water based stuff is more agressive, even if it says no clean think it would be safest to make sure to get all off.

Seen some nasty pics of damaged solder masks in the past. Sorry, no links anymore that forum it was on is down.

Thanks for sharing.   I've contacted Scotle but haven't gotten a response from them.

The LF-4300 from AMTECH is ideal for no-clean applications and also water washable, able to be cleaned using standard aqueous cleaning systems without saponification, according to their site.   How do those ultrasonic cleaners work?   If the machines won't break the bank, I'd be okay with investing in one, to clean the boards.   The stuff I was looking at, I think, was around 200$ - 400$ or so.

[Spork Schivago]

So,

One of my ceramic infrared heating elements came broken.   I believe it was broken during shipping.   It's not a quick fix, it will take a good amount of time.   I was curious though, if I'm going to spend a lot of time getting to the broken one, maybe instead of putting the cheaper ceramic heating elements in there, I should go for nicer ones, like Elstein's.

I was looking at a few of the Elstein products and I like the Elstein SHTS Series.   My current unit has two 150 watt / 230V and it's supposed to have four 600 watt / 230V heating elements.   The Elstein SHTS Series has the 600 watt heating elements but the lowest they go is 300 watt.   Could I just upgrade the two 150 watt units with two 300 watt Elsteins or would more need to be done, like the circuit itself might need to be adjusted?

I thought I'd just purchase four 600 watt / 230V SHTS Series Elstein's and two 300 watt / 230V SHTS Series Elstein's.   The other option would be to purchase the HTS Series I guess.   They make a 150 watt and a 600 watt (around the right sizes as well).

The measurements for my current heating elements are roughly:
240mm x 61mm   (600 watt)
 65mm x 73mm    (150 watt)

The Elstein's seem to come in the following measurements:
   SHTS SERIES (the ones I really like)
=========================
125mm x 125mm    (1200 watt) SHTS
250mm x 62.5mm   (1200 watt) SHTS/1
125mm x 62.5mm   (  600 watt) SHTS/2
62.5mm x 62.5mm  (  300 watt) SHTS/4

      HTS SERIES
=========================
125mm x 125mm     (250, 400, 600, 800, 1000 watt) HTS
250mm x 62.5mm    (250, 400, 600, 800, 1000 watt) HTS/1
 40mm x 62.5mm     (  125, 200, 300, 400, 500 watt) HTS/2
62.5mm x 62.5mm   (    60, 100, 150, 200, 250 watt) HTS/4


I believe there's enough room for the 250mm x 62.5mm HTS/1.   When I was posting these, I just noticed the SHTS/1 is 1200 watt.   I don't think I want to replace all four 600 watt units with the 1200 Elstein ones.   And I think if I went for the much smaller size, 125 x 62.5 SHTS/2, it just wouldn't work.   What do you guys think?

I can also order, what I believe is the exact same replacement for 11$.   I just thought so long as I have it opened, might as well upgrade it with something a little nicer.   From what I've read, low quality IR heating elements have wrecked havoc and are generally discouraged against.

Here's a link to the ones I currently have I believe (the 600 watt ones):
http://www.aliexpress.com/item/Free-shipping-Bottom-ceramic-heating-plate-600W-220V-240-60mm-for-BGA-rework-station/32508868958.html?spm=2114.40010608.4.44.SJfZF9

I guess maybe it's either the Elstein HTS series or just the original low quality ones.

[Deus]

From what I've read, low quality IR heating elements have wrecked havoc and are generally discouraged against.

That's more with full IR machines as preheating is very important in BGA rework.
Too small or low performing heaters can be a pita on heavy mass pcbs.
Has to get up to and keep temps without problems, and fast enough if you want jedec profiles.
On an IR machine SHTS might be a good option due their faster reaction time.

On yours it's more like a preheat/help heater as both top and bottom hot air ar doing the real profile.
The better the IR helps in getting and keeping the pcb up to temps the easier you'll get the profiles as they should.
SHTS would be overkill, HTS is a good option.

Elstein is expensive but would use it again most likely.
If you find them to pricy, infrapara are not bad either, but slower in heating up.
Or ceramicx:   http://www.ceramicx.com/

600w should be more than enough power I guess.
Just check if the SSR and your circtuit/breakers can cope with the total current.

Don't have a US cleaner myself, apart from a small jewelry one to clean my stencils and small stuff.
It is on my wishlist but as I do large pc motherboards sometimes this will reflect in the price...

Anyway, watch out with that flux. I know it's claimed to be no clean but as said, seen pics...
However, Might have been other factors involved too.

[Spork Schivago]

From what I've read, low quality IR heating elements have wrecked havoc and are generally discouraged against.

That's more with full IR machines as preheating is very important in BGA rework.
Too small or low performing heaters can be a pita on heavy mass pcbs.
Has to get up to and keep temps without problems, and fast enough if you want jedec profiles.
On an IR machine SHTS might be a good option due their faster reaction time.

On yours it's more like a preheat/help heater as both top and bottom hot air ar doing the real profile.
The better the IR helps in getting and keeping the pcb up to temps the easier you'll get the profiles as they should.
SHTS would be overkill, HTS is a good option.

Elstein is expensive but would use it again most likely.
If you find them to pricy, infrapara are not bad either, but slower in heating up.
Or ceramicx:   http://www.ceramicx.com/

600w should be more than enough power I guess.
Just check if the SSR and your circtuit/breakers can cope with the total current.

Don't have a US cleaner myself, apart from a small jewelry one to clean my stencils and small stuff.
It is on my wishlist but as I do large pc motherboards sometimes this will reflect in the price...

Anyway, watch out with that flux. I know it's claimed to be no clean but as said, seen pics...
However, Might have been other factors involved too.

Thanks, just wanted to make sure you understand that it's 600 watt per unit, giving me a total of 2,400 watt for the 600 watt ones and 300 watt for the 150 watt ones, or 2,700 watt total for the preheaters.

I'm going to be running (hopefully today) something called 10/2 type UF-B directly from my panel's double pole 30-amp breaker to the work room.   I'll be running the wire to a NEMA 6-30 receptacle.   It's the Turnloc style that I went for.   I wired a NEMA 6-30 plug on the Scotle myself.   From my calculations, 30-amp per hot wire should be more than enough.   This unit is supposed to draw around 4,800 watts.   If I take 4,800 watts and divide it by 240v, I get 20 amps.   I think 10/2 should be enough to handle the 20-amp current.   I'm going to be going around 25 feet.   If anyone thinks my logic is off, please let me know.   AC really isn't my thing.   I asked for help on an electronic forum, just to make sure I do things right.

As for the Elstein's being pricey, you're right.   They are.   I want to build an open-source, open-hardware BGA rework station in the future, when I get better at this.   I figure I can use these cheap ones on this Scotle to experiment with and then when I get it going good, I can just pull the Elstein's from this Scotle here and use them.

Also, going from black to white won't affect much?   You know, the older preheating elements are black, the HTS ones are white...I've contacted Antech Sales asking for a quote.   I asked for the price of four HTS/1, 245mm x 60mm, 600 watt, 230v Elstein heating elements and two HTS/4, 60mm x 60mm, 150 watt,   230v Elstein heating elements.   Hopefully they get back to me soon.

[Deus]

Black bodies emit more radiation, will also absorb more.
But as they are only available in white....
If you have the choice, like I think on ceramicx you can choose between colors, go black.

Mine are white HTS ones too, 800w.
Tried some other controllers a few years ago, 1 resulted in hitting 200c on the pcb in +/- 100 sec.
Pretty good for white heaters I guess

[Spork Schivago]

Thanks Deus.   I figured the colour would matter, I just didn't expect it to matter much.   I figured it'd be negligible.   Thanks for clarifying that.   Unfortunately, from the company I'm going through, I'm going to have three extra 150 watt HTS/4's because the minimum order quantity for that one is 5.   The minimum order quantity for the other size just happens to be how many I need so I'm good there.   I'm a bit confused about what it says on the quote though.

THERE IS A 5 PIECE MINIMUM ORDER QUANTITY ON THIS
PART.
THE FACTORY RESERVCES THE RIGHT TO SHIP AND BILL
FOR AN OVERAGE OF UP TO 2 PIECES ON AN ORDER OF 5-19
PIECES.

I understand the 5 piece minimum part....the other part though, the factory reserves the right to ship and bill for an overage of up to 2 pieces on an order of 5 - 19 pieces....does that mean if I order 5 (I'll be ordering the minimum if I can't find someplace that'd just sell me two pieces), they could bill me for 7, but will only send me 5?    That's weird.   I don't get that.

[uncle_bob]

Thanks Deus.   I figured the colour would matter, I just didn't expect it to matter much.   I figured it'd be negligible.   Thanks for clarifying that.   Unfortunately, from the company I'm going through, I'm going to have three extra 150 watt HTS/4's because the minimum order quantity for that one is 5.   The minimum order quantity for the other size just happens to be how many I need so I'm good there.   I'm a bit confused about what it says on the quote though.

THERE IS A 5 PIECE MINIMUM ORDER QUANTITY ON THIS
PART.
THE FACTORY RESERVCES THE RIGHT TO SHIP AND BILL
FOR AN OVERAGE OF UP TO 2 PIECES ON AN ORDER OF 5-19
PIECES.

I understand the 5 piece minimum part....the other part though, the factory reserves the right to ship and bill for an overage of up to 2 pieces on an order of 5 - 19 pieces....does that mean if I order 5 (I'll be ordering the minimum if I can't find someplace that'd just sell me two pieces), they could bill me for 7, but will only send me 5?    That's weird.   I don't get that.

Hi

When you order 5 pieces they will start a build that is big enough to be *sure* you get your 5 units. If everything goes wrong at the factory, they ship you 5 and yo pay for 5. If everything goes fine at the factory, they get 7 out of the batch and you get them all. They ship you 7 and you pay for 7.

Bob

[Spork Schivago]

Thanks Deus.   I figured the colour would matter, I just didn't expect it to matter much.   I figured it'd be negligible.   Thanks for clarifying that.   Unfortunately, from the company I'm going through, I'm going to have three extra 150 watt HTS/4's because the minimum order quantity for that one is 5.   The minimum order quantity for the other size just happens to be how many I need so I'm good there.   I'm a bit confused about what it says on the quote though.

THERE IS A 5 PIECE MINIMUM ORDER QUANTITY ON THIS
PART.
THE FACTORY RESERVCES THE RIGHT TO SHIP AND BILL
FOR AN OVERAGE OF UP TO 2 PIECES ON AN ORDER OF 5-19
PIECES.

I understand the 5 piece minimum part....the other part though, the factory reserves the right to ship and bill for an overage of up to 2 pieces on an order of 5 - 19 pieces....does that mean if I order 5 (I'll be ordering the minimum if I can't find someplace that'd just sell me two pieces), they could bill me for 7, but will only send me 5?    That's weird.   I don't get that.

Hi

When you order 5 pieces they will start a build that is big enough to be *sure* you get your 5 units. If everything goes wrong at the factory, they ship you 5 and yo pay for 5. If everything goes fine at the factory, they get 7 out of the batch and you get them all. They ship you 7 and you pay for 7.

Bob

Thanks Bob.   They say the first unit is in one of the states but the second item has a 6-8 week wait.   So that means they're probably making them and that's what you're saying, right?  They're going to try and make 7, if they all come out good, I have to pay for 7 and I get 7 and I'll have 5 extra?   But if something goes wrong, I'll just get my 5, I'll pay for 5 and have 3 extra.

I wonder if I can find a place to sell the extra.   I mean I wonder if I'd have any trouble getting rid of them off e-bay.  I guess it might be hard proving they're actual real ones and not counterfeit or something.   If I knew I could sell the extra's for sure, I'd buy them.

[uncle_bob]

Thanks Deus.   I figured the colour would matter, I just didn't expect it to matter much.   I figured it'd be negligible.   Thanks for clarifying that.   Unfortunately, from the company I'm going through, I'm going to have three extra 150 watt HTS/4's because the minimum order quantity for that one is 5.   The minimum order quantity for the other size just happens to be how many I need so I'm good there.   I'm a bit confused about what it says on the quote though.

THERE IS A 5 PIECE MINIMUM ORDER QUANTITY ON THIS
PART.
THE FACTORY RESERVCES THE RIGHT TO SHIP AND BILL
FOR AN OVERAGE OF UP TO 2 PIECES ON AN ORDER OF 5-19
PIECES.

I understand the 5 piece minimum part....the other part though, the factory reserves the right to ship and bill for an overage of up to 2 pieces on an order of 5 - 19 pieces....does that mean if I order 5 (I'll be ordering the minimum if I can't find someplace that'd just sell me two pieces), they could bill me for 7, but will only send me 5?    That's weird.   I don't get that.

Hi

When you order 5 pieces they will start a build that is big enough to be *sure* you get your 5 units. If everything goes wrong at the factory, they ship you 5 and yo pay for 5. If everything goes fine at the factory, they get 7 out of the batch and you get them all. They ship you 7 and you pay for 7.

Bob

Thanks Bob.   They say the first unit is in one of the states but the second item has a 6-8 week wait.   So that means they're probably making them and that's what you're saying, right?  They're going to try and make 7, if they all come out good, I have to pay for 7 and I get 7 and I'll have 5 extra?   But if something goes wrong, I'll just get my 5, I'll pay for 5 and have 3 extra.

I wonder if I can find a place to sell the extra.   I mean I wonder if I'd have any trouble getting rid of them off e-bay.  I guess it might be hard proving they're actual real ones and not counterfeit or something.   If I knew I could sell the extra's for sure, I'd buy them.

Hi

Yes that's my guess on what they are doing. Some places will do it another way. You pay 7X the price for 1 piece as for 7 pieces. At least this way, it is obvious what it going on.

I'd hang on to the spares .. you may need them.

Bob

[Spork Schivago]

Thanks Deus.   I figured the colour would matter, I just didn't expect it to matter much.   I figured it'd be negligible.   Thanks for clarifying that.   Unfortunately, from the company I'm going through, I'm going to have three extra 150 watt HTS/4's because the minimum order quantity for that one is 5.   The minimum order quantity for the other size just happens to be how many I need so I'm good there.   I'm a bit confused about what it says on the quote though.

THERE IS A 5 PIECE MINIMUM ORDER QUANTITY ON THIS
PART.
THE FACTORY RESERVCES THE RIGHT TO SHIP AND BILL
FOR AN OVERAGE OF UP TO 2 PIECES ON AN ORDER OF 5-19
PIECES.

I understand the 5 piece minimum part....the other part though, the factory reserves the right to ship and bill for an overage of up to 2 pieces on an order of 5 - 19 pieces....does that mean if I order 5 (I'll be ordering the minimum if I can't find someplace that'd just sell me two pieces), they could bill me for 7, but will only send me 5?    That's weird.   I don't get that.

Hi

When you order 5 pieces they will start a build that is big enough to be *sure* you get your 5 units. If everything goes wrong at the factory, they ship you 5 and yo pay for 5. If everything goes fine at the factory, they get 7 out of the batch and you get them all. They ship you 7 and you pay for 7.

Bob

Thanks Bob.   They say the first unit is in one of the states but the second item has a 6-8 week wait.   So that means they're probably making them and that's what you're saying, right?  They're going to try and make 7, if they all come out good, I have to pay for 7 and I get 7 and I'll have 5 extra?   But if something goes wrong, I'll just get my 5, I'll pay for 5 and have 3 extra.

I wonder if I can find a place to sell the extra.   I mean I wonder if I'd have any trouble getting rid of them off e-bay.  I guess it might be hard proving they're actual real ones and not counterfeit or something.   If I knew I could sell the extra's for sure, I'd buy them.

Hi

Yes that's my guess on what they are doing. Some places will do it another way. You pay 7X the price for 1 piece as for 7 pieces. At least this way, it is obvious what it going on.

I'd hang on to the spares .. you may need them.

Bob

Uncle Bob,

Can you go a bit more in detail as to why I might need these later on and why it'd be a good idea to hang onto them?   Do IR heaters fail fairly often?   If they got a very long shelf life, I guess I'll hang on to them.   Maybe I can use them in other projects if I don't use them later on in life on this heating unit.

[uncle_bob]

Hi

Think of an IR heater as a long life light bulb. They last forever and ever on the shelf. They rarely die, but they do have a finite life span. The real issue is that unlike light bulbs, they are (as you now know) custom made. Eventually the factory stops doing this or that model even as a custom. Does that happen 5 years from now or 50 years? Who knows ....

Bob

[Deus]

Life span depends on how you use them.

"The service life of infrared radiators depends on the use
conditions and the radiator operating temperatures.
The following table contains details of the service
life of Elstein radiators (230 V) when operated under
normal conditions:

at 400 °C approx. 20.000 hours (e.g. FSR 250 W)
at 700 °C approx. 10.000 hours (e.g. FSR 1000 W)
at 900 °C approx. 8.000 hours (e.g. HTS 1000 W)
at 1100 °C approx. 2.000 hours (e.g. HLS 750 W)"

Btw, the heaters you talk about now are elstein? Or other manufacturer?
Tbh, although Elstein are better compared to Chinese, think you can just as well get some cheaper Chinese ones to save money.
Unless you want them to heat up faster, if that's not really an issue, you can allways add a 1-2 minute to say 80-120c for the IR plates, then start your profile.

[Spork Schivago]

Hi

Think of an IR heater as a long life light bulb. They last forever and ever on the shelf. They rarely die, but they do have a finite life span. The real issue is that unlike light bulbs, they are (as you now know) custom made. Eventually the factory stops doing this or that model even as a custom. Does that happen 5 years from now or 50 years? Who knows ....

Bob

That's why I gotta order five to seven of those 150 watt ones I bet!   They only fire up the kiln or whatever it's called when someone places an order for them I bet.   It's a weird size to begin with and then on top of that, a very small wattage.   I don't think a lot of people order the 150 watt square ones.    And then there's the issue it being an older model.   I would have went for the SHTS ones, the black ones, if they had the right size and temperature.   I saw on the datasheet how they could do custom sizes but I bet that'd cost an arm and a leg.   If I was order like 100 of them, maybe they'd do it.   But for 6 ceramic heating elements, I bet they'd charge a lot.   2 different custom sized ones would cost a bit.

[Spork Schivago]

Life span depends on how you use them.

"The service life of infrared radiators depends on the use
conditions and the radiator operating temperatures.
The following table contains details of the service
life of Elstein radiators (230 V) when operated under
normal conditions:

at 400 °C approx. 20.000 hours (e.g. FSR 250 W)
at 700 °C approx. 10.000 hours (e.g. FSR 1000 W)
at 900 °C approx. 8.000 hours (e.g. HTS 1000 W)
at 1100 °C approx. 2.000 hours (e.g. HLS 750 W)"

Btw, the heaters you talk about now are elstein? Or other manufacturer?
Tbh, although Elstein are better compared to Chinese, think you can just as well get some cheaper Chinese ones to save money.
Unless you want them to heat up faster, if that's not really an issue, you can allways add a 1-2 minute to say 80-120c for the IR plates, then start your profile.

Hrmm, I am talking about the Elstein ones now, the HTS series.   I was getting ready to place an order.   Someone said because the main reflow is going to be done with hot air, these IR plates won't make much difference, you seem to agree with them.   I had read how cheap heating elements caused all kinds of issues in the beginning and then people learned their lessons and started using better quality ones.   That article was for IR BGA Rework Stations only though, not a hybrid like I have.

I wanted something real nice.   I thought if I replaced all these cheap chinese ones with the nice Elstein ones, I could start experimenting with the cheap ones.   I'd like to make my own BGA rework station, open source, open hardware, one of these days, for the whole world to share and contribute to.   I thought instead of playing with really expensive ones, I'd just use these.   But now I'm questioning it all together....

The cheap chinese one is around 11$.   There's probably shipping charges.   It's from China and I'd be ordering from AliExpress I think it's called.   The Elstein's would be around 352$ plus shipping.    That's a huge difference in price....

Is there a chance that these cheap ones could be putting out different amounts of heat?   I'm sure there's some sort of percentage of error, right?   Like if I'm running the four 600 watt units at 230VAC, would they all, for the most part, put out the same amount of heat?   I don't think there's a separate thermocouple per heating element.   If it were my design, I'd probably use the heating elements that had the thermocouples built in so I could monitor the temp of each heating element independently.

With this unit, there appears to be just one thermocouple to monitor the pre-heaters.   It's in the middle on the outer edge.   I can't adjust it.   I think it's supposed to give me an idea of what the board temp is.   I'm not certain yet.

If one heating element was putting out something like 150 degrees C, but the other heating element was putting out something like 100 degrees C, and the other one was putting out 123 degrees C, would it cause problems?   I've noticed with my much smaller Weller, when I try to preheat a larger board, one that it wasn't designed to handle, it actually seems to warp the board a bit.    I'd imagine something like uneven heating with the heating elements could cause a similar issue...

[Deus]

Someone said because the main reflow is going to be done with hot air, these IR plates won't make much difference, you seem to agree with them.   I had read how cheap heating elements caused all kinds of issues in the beginning and then people learned their lessons and started using better quality ones.   That article was for IR BGA Rework Stations only though, not a hybrid like I have.

Yes, I posted that before too. It's only preheating the area around the bga to prevent heat loss. The more copper planes, the more heat gets drawn away. By heating up the surrounding area with IR the 2 hot air heaters can do a better job without to much temperature loss.

I wanted something real nice.   I thought if I replaced all these cheap chinese ones with the nice Elstein ones, I could start experimenting with the cheap ones.

Well, before you spend lots of money... get your machine up and running. Just replace the broken heater. Or replace them all with higher wattage ones if you insist on that.
(It will be an improvement probably)
Learn the machine. Get some experience in BGA rework. If it gets you some money, you can save up for other heaters later if you still want to build an IR machine.
IR can be a pita on sensitive chips.

The cheap chinese one is around 11$.   There's probably shipping charges.   It's from China and I'd be ordering from AliExpress I think it's called.   The Elstein's would be around 352$ plus shipping.    That's a huge difference in price....

See above, Maybe get 1 or 2 extra, in case one breaks?

Is there a chance that these cheap ones could be putting out different amounts of heat?   I'm sure there's some sort of percentage of error, right?   Like if I'm running the four 600 watt units at 230VAC, would they all, for the most part, put out the same amount of heat?   I don't think there's a separate thermocouple per heating element.   If it were my design, I'd probably use the heating elements that had the thermocouples built in so I could monitor the temp of each heating element independently.

Even elsteins won't allways have exact same temps.

With this unit, there appears to be just one thermocouple to monitor the pre-heaters.   It's in the middle on the outer edge.   I can't adjust it.   I think it's supposed to give me an idea of what the board temp is.   I'm not certain yet.

Not for board temps. It's for the IR plates temps. You should test what setting gives the needed result on the pcb you rework.
On mine however I changed it so I can read bottom pcb temp, But again, mine is IR only, both top and bottom.

If one heating element was putting out something like 150 degrees C, but the other heating element was putting out something like 100 degrees C, and the other one was putting out 123 degrees C, would it cause problems?   I've noticed with my much smaller Weller, when I try to preheat a larger board, one that it wasn't designed to handle, it actually seems to warp the board a bit.    I'd imagine something like uneven heating with the heating elements could cause a similar issue...

Yes, better to get even heating. But again, on yours the hot air is doing the actual work. If the difference is not to much...

[Spork Schivago]

Thanks for responding.

I figured even with the best money could buy, there's always be some sort of percentage of error.   I just figured the cheaper the heating element, the larger the percentage of error, you know?

I think I'll go for the cheaper Chinese one, make some cash, and then if it pays off, go for the nicer ones and go from there.

You said something along the lines of, "It's for the IR plates temps. You should test what setting gives the needed result on the pcb you rework."

What do you mean by test what setting gives the needed results on the PCB I rework?   Do you mean measure the PCB's temperature and see how far off it is from what those IR plate thermocouples read?   I wonder if I could calibrate the unit somehow so whatever temp that thermocouple is reporting is more or less the temp of the board.   I wonder if that'd be helpful at all.   Thanks for the help!

I got the 240V AC ran into the work room now.   That was a good two days worth of work.   I had to cut the sheetrock and run wire.   I never did anything like that before, so it was all new.   I think if I had to do it over again, I could get it done in a couple hours instead of two days.

[Deus]

You said something along the lines of, "It's for the IR plates temps. You should test what setting gives the needed result on the pcb you rework."

What do you mean by test what setting gives the needed results on the PCB I rework?   Do you mean measure the PCB's temperature and see how far off it is from what those IR plate thermocouples read?   I wonder if I could calibrate the unit somehow so whatever temp that thermocouple is reporting is more or less the temp of the board.   I wonder if that'd be helpful at all.   Thanks for the help!

Do you mean measure the PCB's temperature and see how far off it is from what those IR plate thermocouples read?

Yes, all the machines I know of work like this, with IR plate temps, not pcb temps.

I wonder if I could calibrate the unit somehow so whatever temp that thermocouple is reporting is more or less the temp of the board.   I wonder if that'd be helpful at all.   Thanks for the help!

Test firts, if it does seem to reflect pcb temps it might have an offset values set. Doubt it, but who knows...
Or change the TC so you can measure pcb temps instead of IR temps with it.
However, once you know the settings for your machine's IR plates...