Iron upgrade, new learning curve?

[technix]

I just ditched my old non-temperature-regulated soldering iron in favor of an ATTEN 936 (a Hakko 936 clone I bought for about US$40) but I find its operation very different from that old copper-tipped iron. Is there any advices for this transition?

[Simon]

whats the problem ? the material of the tip should not make much difference.

[technix]

whats the problem ? the material of the tip should not make much difference.

My old iron tip can hold a copious amount of molten solder on it and have a hell lot of thermal mass, so the procedure of soldering SMT components are usually let the tip hold some solder, place the component on the board, touch the joint with the tip of the iron (during which the big thermal mass will almost instantly bring both the cap/pin of the component and the pad up to the right temperature and the held solder just flows to form a nice solder joint) and then proceed with the other pin. However this wears the tip down very quickly. Also if I accidentally got too much solder on a joint I can just scoop away the excess solder using that big heavy tip.

The 936's tip does not hold solder at all and don't have much thermal mass, so my old tricks no longer works.

[Simon]

you may need to turn the heat up a bit and hope that the feedback system is fast enough.

[Chris C]

You could grow a third hand.  Giving you one to hold the SMD in place, one to hold the iron, and one to hold the solder since the iron won't do it.

I tried and couldn't, so even if I'm primarily using solder on a spool, I find myself using solder paste for the first SMD pad.  Just a bit, dabbed on with a toothpick.  Then one hand holds the SMD (or tool holding it), the other the iron.  Once that joint cools, the SMD isn't going anywhere, so I have a hand free to hold solder and do the other pads.  I can come back to the first pad last and apply a bit more solder if needed.

[continuo]

Well, tinnig the tip and carrying the molten solder to the joint isn't exactly the recommended procedure, at least not without the use of additional flux at the joint. There are a lot of smd soldering tutorials on youtube, it may be helpful to watch a few of these 

[jitter]

First of all, getting the right tip for the job is crucial. Too big and it won't fit, too small and it won't solder properly (the thermal mass you mention).
Second, the right temperature. Ballpark: 325 C for leaded and 350 C for unleaded (or should that be leadfree?  )
Third: the right solder wire gauge. Thin for small, thicker for bigger parts (in that respect I disagree with Dave of just using thin gauge for everything).
Fourth: the component must lie flat before you solder it.
Fifth: the only proper solder join is made when you feed in the wire during soldering. Putting solder on the tip and then try to solder with that is not a good practice. The one thing that you need for a proper join (the flux inside the wire) has lost its effectivity before you can even solder that way.

Wen I have to replace an SMD resistor, and should I choose to use the iron and not hot air, then I remove the old one, remove the existing solder from both pads and apply a bit of new solder to only one of the pads. Then I place the new resistor on the pads and touch the pad with solder until it melts for a join that's good enough to hold it in place. This way the resistor lies flat. Then I solder the other side and redo the first side for a quality join. Job done.

[technix]

First of all, getting the right tip for the job is crucial. Too big and it won't fit, too small and it won't solder properly (the thermal mass you mention).
Second, the right temperature. Ballpark: 325 C for leaded and 350 C for unleaded (or should that be leadfree?  )
Third: the right solder wire gauge. Thin for small, thicker for bigger parts (in that respect I disagree with Dave of just using thin gauge for everything).
Fourth: the component must lie flat before you solder it.
Fifth: the only proper solder join is made when you feed in the wire during soldering. Putting solder on the tip and then try to solder with that is not a good practice. The one thing that you need for a proper join (the flux inside the wire) has lost its effectivity before you can even solder that way.

Wen I have to replace an SMD resistor, and I choose to use the iron and not hot air, the I remove the old one, remove the existing solder from both pads and apply a bit of new solder to only one of the pads. Then I place the new resistor on the pads and touch the pad with solder until it melts for a join that's good enough to hold it in place. This way the resistor lies flat. Then I solder the other side and redo the first side for a quality join. Job done.

I use RoHS thin-guage solder only, and my solder does not have a resin core, so there is no difference between running the wire through and tinning the tip and dip later. Big tip trouble was very prominent when I was assembling my M102 and M171 boards as it features some very tightly packed chips.

[bitwelder]

First of all, getting the right tip for the job is crucial. Too big and it won't fit, too small and it won't solder properly (the thermal mass you mention).

And on the subject of getting the right tip, buying a genuine Hakko tip might help as well.

[jitter]

IMHO, flux cored (be it resin or otherwise) solder is the only suitable solder for electronics. So much so that I would NEVER consider using any other type of solder.

Usually, the flux core of solder wire is of the so called "no clean" type meaning you can leave the residue on. Sure, it looks a bit messy, but has no adverse affects.
Add on flux, gel or fluid, usually must be cleaned afterwards.

In my job I mainly deal with sensitive measurement instruments with high impedance (GOhms, TOhms). Add on flux wreaks havoc to that because it causes leakage, so I avoid it as much as possible. In my experience, the flux core of no clean solder wire has no discernable effect on these instruments.

My advice would be to get yourself flux cored solder.

Add on flux is useful for soldering fine pitch ICs to prevent short circuits. You can use a hollow tip and use the drag method.

[TheAmmoniacal]

I have the same station (Hakko 936 clone), and I can confirm it doesn't hold solder very well. I'm pretty sure this is all due to the tip construction, I'd recommend getting an original tip (not one supplied with a clone unit) - hook style works the best for me (J-shape). Also, Tip Tinner compound works wonders: http://www.mcmelectronics.com/product/MULTICORE-LOCTITE-MM01921-/21-1075

The other option is just getting a $40 hot air station!

[MarkF]

I just bought a HAKKO FX888D and have similar questions.  Being use to a 25 watt pencil iron, I'm having trouble selecting the temperature.  From what I've read, I should be in the 315^oC to 400^oC.  I have always used leaded flux core solder in varies sizes.  Never tried the lead-free solder.

As far as techniques, the following videos might help:
     and 

[rob77]

325 C for leaded and 350 C for unleaded (or should that be leadfree?  )

isn't that a bit high ? many components have max ratings in datasheets  320C for max 3 seconds.

i'm using 260-280 for leaded, for sensitive parts even less 250-260C and for lead-free i'm cranking up to 280-320. using a solomon SL-20 iron  - it's a well built soldering station , but it's "ancient" in terms of design.

[MarkF]

i'm using 260-280 for leaded, for sensitive parts even less 250-260C and for lead-free i'm cranking up to 280-320. using a solomon SL-20 iron  - it's a well built soldering station , but it's "ancient" in terms of design.

The FX888D manual specifies 250^oC for tip maintenance.  I took that to mean that temp. is sufficient to inspect and tin the tip but too low for soldering.

[jitter]

325 C for leaded and 350 C for unleaded (or should that be leadfree?  )

isn't that a bit high ? many components have max ratings in datasheets  320C for max 3 seconds.

i'm using 260-280 for leaded, for sensitive parts even less 250-260C and for lead-free i'm cranking up to 280-320. using a solomon SL-20 iron  - it's a well built soldering station , but it's "ancient" in terms of design.

At work I use JBC irons that have a pretty precise control over the temperature of the tip. This is also checked every year with a special tool (ISO requirement).
At home I have a Solomon SL-20 too, and I would set that one lower, indeed. But my guess is that the actual temp of the tip might be some tens of degrees off...

325 C and 350 C are ballpark figures. In the training we get, usually they say that you must use the lowest possible temp to get a good quality join within a short enough time. Of course that depends on several factors, so I just stick to those ballpark figures and only deviate from it when neccessary.

3 seconds at 320 C is much more time than you need. With practice and experience, you will find a temperature and method that allows you to do most joins in 1 s (2 s tops).
I'd rather solder for 1 s at 350 C than for 3 at 320 C. The end-result is that the former might actually lead to less heating of the component than the latter.

Only joins on which large amounts of copper take away the heat might take longer, but then the heat is taken away...

[rob77]

i'm using 260-280 for leaded, for sensitive parts even less 250-260C and for lead-free i'm cranking up to 280-320. using a solomon SL-20 iron  - it's a well built soldering station , but it's "ancient" in terms of design.

The FX888D manual specifies 250^oC for tip maintenance.  I took that to mean that temp. is sufficient to inspect and tin the tip but too low for soldering.

if the solder wets the soldered surface then the temperature is OK - saying 250C is too low is not right ... especially for low temperature solders

[MarkF]

i'm using 260-280 for leaded, for sensitive parts even less 250-260C and for lead-free i'm cranking up to 280-320. using a solomon SL-20 iron  - it's a well built soldering station , but it's "ancient" in terms of design.

The FX888D manual specifies 250^oC for tip maintenance.  I took that to mean that temp. is sufficient to inspect and tin the tip but too low for soldering.

if the solder wets the soldered surface then the temperature is OK - saying 250C is too low is not right ... especially for low temperature solders

That sounds like a special case and not the norm???

[jitter]

Low temperature solders are a special case. In one of the vids Dave explains that this kind of solder is used to remove hard to desolder components but that that low temp solder is not to be used for a normal join (brittle).

[MarkF]

I just saw that video.  He removed some large SMD chips to demonstrate reworking.  That solder was specifically for de-soldering.
In his first soldering demo video, he suggested 350^oC to 400^oC.  With special case minimums of 280^oC.

[rob77]

ok , then go ahead and solder at 400C at that temperature you significantly reduce the lifespan of your tip and heating element. not talking about allowed temp range for parts (usually upto 320-350C max) .. further issues are lifting PCB tracks and burning/oxidizing the solder.

[continuo]

A quick check on the technical datasheet of your solderwire may give you some hint on correct working temperature. I'm currently using Interflux IF14 63/37 (leaded) and they recommend 320...360 °C

http://www.interflux.com/sites/default/files/documents/en/TD%20IF%2014-06-09-14_0.pdf

[rob77]

and quick check on stuff i'm soldering says 260C max 1,6mm from package  - for SOIC the 1,6mm from package is  pretty much the end of the lead - so no temperature gradient game possible....  for DIP (much less common nowadays) you have some room because of the pin length and the temp gradient (you touch the end of the lead with 300C and you're still on the safe side1,6mm from the package for a second or so...)

in fact i don't care if you solder with a propane torch at 500C or whatever you like or works for you...... i'm just saying the 300+C is a bit too high for many components.

[jitter]

... i'm just saying the 300+C is a bit too high for many components.

Well, in my 15 years in industrial electronics, I've been consistently taught to hand solder at 325 C (Pb) and 350 C (LF) in several solder courses. As I said before, ballpark figures.
But in those years, the only failures I caused on new components were with hot air. Not a single one with an iron set to 325 or 350 C.

However, a solder wave must not be so hot. We desolder DIP packages and similar on a small wave set to 250 C (Pb). The huge amount of solder makes this possible whereas the thermal mass of the tip doesn't.

[amyk]

Especially with the cheaper irons, you should check the temperature calibration, since it could be far off. Note also that an overly loose tip or otherwise poor thermal contact between the tip and heater will make it difficult to maintain the right temperature.

[Monkeh]

i'm just saying the 300+C is a bit too high for many components.

Bullshit, standard iron temperature is around 350C.

[G7PSK]

I run my iron at 300 deg C. Those conical bits useless in my opinion, get a few chisel bits of various sizes.
It is also far easier to use solder paste for SMD work even if you are using an iron, that way you put the solder and flux on the board then you can put the component down and hold it in place with one hand and use the iron with the other.

[rob77]

i'm just saying the 300+C is a bit too high for many components.

Bullshit, standard iron temperature is around 350C.

datasheets say 260C max but it's a bullshit because Monkeh said so... 

[Monkeh]

i'm just saying the 300+C is a bit too high for many components.

Bullshit, standard iron temperature is around 350C.

datasheets say 260C max but it's a bullshit because Monkeh said so... 

So take a look at every soldering system out there. The ones with fixed temperatures, the ones with variable.. they all run >300C for normal soldering.

There are very few components which will be worried by this, and even the ones which really are sensitive to high temperatures simply require quick soldering in most cases. It takes time to heat them up.

My soldering iron runs nearly 400C so it must break things because rob77 said so...

[continuo]

Metcal SmartHeat tips run at fixed temperatures, and, as far as I know, there are no standard tips below 300°C available. "Temperature Sensitive" 600 series tips run at around 675F (357°C)... Someone should tell Metcal that their irons are to dangerous to be used on electronics 

[jitter]

i'm just saying the 300+C is a bit too high for many components.

Bullshit, standard iron temperature is around 350C.

datasheets say 260C max but it's a bullshit because Monkeh said so... 

I'd like to see that datasheet. Could you provide a link, please?

[GreyWoolfe]

Metcal SmartHeat tips run at fixed temperatures, and, as far as I know, there are no standard tips below 300°C available. "Temperature Sensitive" 600 series tips run at around 675F (357°C)... Someone should tell Metcal that their irons are to dangerous to be used on electronics 

Uh oh, I'm in trouble.  I just bought 3 600 series chisel tips for my MX-500   I guess I will have to go out back and cut my own switch.

[rob77]

i'm just saying the 300+C is a bit too high for many components.

Bullshit, standard iron temperature is around 350C.

datasheets say 260C max but it's a bullshit because Monkeh said so... 

I'd like to see that datasheet. Could you provide a link, please?

sure here they are:

examples of devices with 260C max lead temperature 1,6mm from case - LF353 my favorite jfet opamp and also the most jelybean opamp ever - LM358

http://www.ti.com/lit/ds/symlink/lf353.pdf
http://www.ti.com/lit/ds/symlink/lm158-n.pdf

some devices with 300C max from TI (just to prove they don't have 260C everywhere). the jelybean jfet opamps TL08x and 555
http://www.ti.com/lit/ds/symlink/tl084.pdf
http://www.ti.com/lit/ds/symlink/ne555.pdf

[jitter]

Those specs are for reflow- and wave soldering processes. Look at the times: 10 to 60 seconds!
When hand soldering at 350 C for a couple of seconds per pin, you're not even going to come close.

Take a look at the datasheet of this miniature relay (page 3). These are solder profiles for the different types of process and almost all components have these (otherwise it would be difficult to make pcbs with a lot of different components).

In fact, very few components do no stand up to such a solder profile... guess what... we hand solder these instead at 350 C!

The amount of energy you put into a component does not depend only on the temperature, also on the time it takes.

I'm thinking about what kind of components we hand solder... certain types of precision capacitors, certain capacitors with plastics that melt easily, those Caddock (or other brand) ceramic thin film resistors that EEVblog did a video (#730) on (those pins are attached with solder), some relays that might otherwise break their seals... All in all very few.

[rob77]

Those specs are for reflow- and wave soldering processes. Look at the times: 10 to 60 seconds!
When hand soldering at 350 C for a couple of seconds per pin, you're not even going to come close.

sometimes manufacturers specify the hand soldering in datasheets as well and it usually 300,320 or i seen some parts even with 350C for 3 seconds...
but still doesn't change the facts i posted earlier -
1. for some components the 350C is too high
2. i'm using the temperatures as described earlier 250-320 - most of the time @ 270C.

and i'm not saying you'll destroy the parts with higher temperature - when i was a kid a was soldering with a soldering gun - that ramps up to 400C+ in seconds.

[jitter]

Most important thing is that you get a good join without overheating the component. If you can achieve that at a lower temperature, then that is fine. But, if that lower temperature should require more than a few seconds then you're likely putting more energy into that component than you would at a higher temperature. It's all a balance between time and temperature. Neither must be too long or too high.

[technix]

i'm just saying the 300+C is a bit too high for many components.

Bullshit, standard iron temperature is around 350C.

datasheets say 260C max but it's a bullshit because Monkeh said so... 

I'd like to see that datasheet. Could you provide a link, please?

sure here they are:

examples of devices with 260C max lead temperature 1,6mm from case - LF353 my favorite jfet opamp and also the most jelybean opamp ever - LM358

http://www.ti.com/lit/ds/symlink/lf353.pdf
http://www.ti.com/lit/ds/symlink/lm158-n.pdf

some devices with 300C max from TI (just to prove they don't have 260C everywhere). the jelybean jfet opamps TL08x and 555
http://www.ti.com/lit/ds/symlink/tl084.pdf
http://www.ti.com/lit/ds/symlink/ne555.pdf

Oh noes... the M102v4-10 which motivated me to buy this soldering station uses one from the following as the op amp: LM358, TLC2272, LF353 and TL082... Should I just, from this point on, socket any chip I use on my boards, just to prevent overheating the pins of the chips?

By the way, excessive heat during soldering can damage a chip if done with excessive violence - I destroyed 4 SDB628 chips from this (and this not-so-trivial-to-design boost SMPS chip let the smoke out of a few inductors and even almost ignited itself once, with only 5W of input power ).

[MarkF]

I just looked up the specs on my goto Weller 25W iron.  The tip temperature is 750^oF (400^oC). 
Not what I expected.

[Monkeh]

1. for some components the 350C is too high

A very very very few. None of those you've listed.

2. i'm using the temperatures as described earlier 250-320 - most of the time @ 270C.

And you probably need to heat for longer to get up to temperature, to gain nothing.

[tautech]

I'm with Monkeh on this subject that is more complex than many might think.

Solder type, Tip type, Rework, Device thermal mass, Ground planes and the affect all these have on soldering ease.
Personally I rarely ever look at Temp settings and go by "feel" and flux "flash off".
How many of us have a properly Cal'ed solder station for perfect settings, not required for hobbyist work IMHO.
Combine this with a few different solder types of your preference and you can tie youself in a knot. 

Sure small SMD on SS PCB's need bugger all heat but a 4+ layer PCB with large components is a different matter. 
Had to get a domestic heat gun out the other day for a 30 pad socket removal when the rework hot air just wouldn't cut the mustard.

Horses for courses and practice. 

[KL27x]

My old iron tip can hold a copious amount of molten solder on it and have a hell lot of thermal mass, so the procedure of soldering SMT components are usually let the tip hold some solder, place the component on the board, touch the joint with the tip of the iron.

What you're describing is a type of drag soldering. The success of this type of soldering is highly dependent on tip shape. Some tips shapes are meant to hold solder (chisel/bevel), and some aren't.

A fine conical tip is the worst kind for this, since it will tend to suck solder away from the tip, up the shaft. With a blunter conical, this technique will work great. 0.2-0.5mm tips are my preference for conicals, for general board-level use.

Also if I accidentally got too much solder on a joint I can just scoop away the excess solder using that big heavy tip.

It sounds to me like you continually created your own tinned-face-only tip with your cheap iron, by applying solder to one spot and letting the rest of the tip oxidize.

If you like to drag solder, I recommend (besides using flux), see if you can find a bevel tip with a tinned face, only. This is denoted by "CF" in the part number. When you use this kind of tip, it holds solder right on the tip, where you want it. And paradoxically, it will suck excess solder out of the joint. So it applies solder, copiously, but leaves only a small amount. In fact,
if you slightly turn the beveled face away from the joint, it will magically remove any bridges left from a reflow oven, etc. Because the entire tinned surface is a flat disc, the surface tension of the molten solder acts like a directional vacuum that melts solder at the edges of the disc and pulls it towards the center (having the beveled tip keeps the surface roughly flat to the board, so this action doesn't have to work against gravity). With a tip like this on your iron, you can throw away your solder wick and desoldering pump. The downside of a CF tip is that it's directional and you can't feed solder onto the top/side while doing lots of solder-hungry connections. You have to lay your solder down on your bench and melt from the top, or you have to turn the tip to apply solder. It's sort of a dedicated tip. For lots of point to point soldering and thru hole parts where you're burning through spools of solder, it's more cumbersome that it's worth. For SMD, only, it can get most any job done, efficiently, with a small learning curve.



Some say a hollow core tip or a spoon tip are the key for drag soldering (CM). They don't make a CM for my iron, so I can't compare. The CF, tinned face-only, makes this technique foolproof.

[technix]

My old iron tip can hold a copious amount of molten solder on it and have a hell lot of thermal mass, so the procedure of soldering SMT components are usually let the tip hold some solder, place the component on the board, touch the joint with the tip of the iron.

What you're describing is a type of drag soldering. The success of this type of soldering is highly dependent on tip shape. Some tips shapes are meant to hold solder (chisel/bevel), and some aren't.

A fine conical tip is the worst kind for this, since it will tend to suck solder away from the tip, up the shaft. With a blunter conical, this technique will work great. 0.2-0.5mm tips are my preference for conicals, for general board-level use.

Also if I accidentally got too much solder on a joint I can just scoop away the excess solder using that big heavy tip.

It sounds to me like you continually created your own tinned-face-only tip with your cheap iron, by applying solder to one spot and letting the rest of the tip oxidize.

If you like to drag solder, I recommend (besides using flux), see if you can find a bevel tip with a tinned face, only. This is denoted by "CF" in the part number. When you use this kind of tip, it holds solder right on the tip, where you want it. And paradoxically, it will suck excess solder out of the joint. So it applies solder, copiously, but leaves only a small amount. In fact,
if you slightly turn the beveled face away from the joint, it will magically remove any bridges left from a reflow oven, etc. Because the entire tinned surface is a flat disc, the surface tension of the molten solder acts like a directional vacuum that melts solder at the edges of the disc and pulls it towards the center (having the beveled tip keeps the surface roughly flat to the board, so this action doesn't have to work against gravity). With a tip like this on your iron, you can throw away your solder wick and desoldering pump. The downside of a CF tip is that it's directional and you can't feed solder onto the top/side while doing lots of solder-hungry connections. You have to lay your solder down on your bench and melt from the top, or you have to turn the tip to apply solder. It's sort of a dedicated tip. For lots of point to point soldering and thru hole parts where you're burning through spools of solder, it's more cumbersome that it's worth. For SMD, only, it can get most any job done, efficiently, with a small learning curve.



Some say a hollow core tip or a spoon tip are the key for drag soldering (CM). They don't make a CM for my iron, so I can't compare. The CF, tinned face-only, makes this technique foolproof.

I gave up the conical tip in favor of a beveled tip and I love it - old tricks coming back again and the new tip, once again, have enough thermal mass to pull off that trick.

[MarkF]

Hakko has a nice page on tip selection for drag soldering.

[nanofrog]

Some say a hollow core tip or a spoon tip are the key for drag soldering (CM). They don't make a CM for my iron, so I can't compare. The CF, tinned face-only, makes this technique foolproof.

FWIW, I have both, and for SMD drag soldering, I prefer the spoon/hollowed versions (bit better at reducing bridges/drawing them out IME). I find the flat face/hoof takes a smidge more skill for drag soldering, but is more flexible regarding the tasks it can do.

And you really can continuously feed solder during the drag process with practice.  Feed the solder from the backside of the tip as you pull toward the solder & across the pins; this way you're feeding as you pull, and the excess solder stays on the tip's face (assuming you don't over-feed).

Hakko's site illustrates this rather well IMHO (I would add large metal tabs to that list).



BTW, what iron are you using that doesn't offer dedicated drag tips?

[m98]

As far as techniques, the following videos might help:

They show very good technique, but who applies that? I mean, they even clean the solder...

[MarkF]

As far as techniques, the following videos might help:

They show very good technique, but who applies that? I mean, they even clean the solder...

Just those that are going to the moon...

He has 5 videos on soldering.  His soldering process does seem to be over the top. 
But, the solder joints sure are pretty.  Makes you wonder if there is something to it.....

[wraper]

Those specs are for reflow- and wave soldering processes. Look at the times: 10 to 60 seconds!
When hand soldering at 350 C for a couple of seconds per pin, you're not even going to come close.

sometimes manufacturers specify the hand soldering in datasheets as well and it usually 300,320 or i seen some parts even with 350C for 3 seconds...
but still doesn't change the facts i posted earlier -
1. for some components the 350C is too high
2. i'm using the temperatures as described earlier 250-320 - most of the time @ 270C.

and i'm not saying you'll destroy the parts with higher temperature - when i was a kid a was soldering with a soldering gun - that ramps up to 400C+ in seconds.

You don't take into account that they specify solder, not tip temperature. Tip temperature != solder temperature.

[KL27x]

Doesn't matter how the temperature of the tip is set. On a sensitive component, like say an SMD ceramic resonator, you can kill it at just about any temperature that solder will reflow, nicely.

A soldering iron cannot control duration. It's up to the user. Using the appropriate tip and with the right experience and dexterity, you can solder anything despite lack of fine control over the temperature. I have looked at the temperature knob on my iron, never. It doesn't matter what the numbers say. I turn it up or down as I see fit by the results, not because of what the dial says.