SMD Soldering Practice Boards

[xrunner]

So that's about 10 days for delivery of a PC board with about 100 components from China for $4.25 plus $1.00 shipping and a free shipment of 10 breadboard jumper cables within the first 8 days just to maintain customer satisfaction.

Amazing customer service! 

Wow - that's a great outcome.

I just ordered a pair of Mastech SMD RC tweezers. The other piece of junk I got that uses an external DMM wasn't worth spit.

[zapta]

Wow - that's a great outcome.

I just ordered a pair of Mastech SMD RC tweezers. The other piece of junk I got that uses an external DMM wasn't worth spit.

The MS8910 are very useful for smd work. Amazon sells also another Mastech kind that is more expensive and seems to have crappie tips http://amzn.com/B000WZVQR4

I carefully filed the tips of the MS8910 to have better mechanical matching. Also, if you turn it off (rather than let it shut off), you need to press longer to turn it on again (I didn't realize that and thought that it's dead).

[Electro Fan]

Slightly off topic but two questions: 

1) Does anyone know if there is a "gullwing" tip for a Weller WESD51 soldering iron?  If not, what would be the next best Weller (WESD51 compatible) tip for SMD drag soldering? 

2) I've been using Kester 48 lead-free RA solder .031" and it works pretty well but I'd like to try the same or something similar in .020"; Kester makes this in a 1lb reel  but I'd like to try it in a smaller package first - anyone know of such a product (Lead Free RA .020 in a package one ounce or less)?  From Kester would be great but I'm open to other recommended brands.

Thx

[nanofrog]

1) Does anyone know if there is a "gullwing" tip for a Weller WESD51 soldering iron?  If not, what would be the next best Weller (WESD51 compatible) tip for SMD drag soldering?

Doesn't appear they make a dedicated tip (gull wing, spoon, ...), but you can use others.

Chisels, hoof types, and knife shapes will all work (just need to develop your technique). Hoof would probably be easiest (they're calling them single flat, such as the ETDD). Between a chisel or knife, the knife should be a little easier IMHO.

Photo of an ETDD (largest hoof offered):

2) I've been using Kester 48 lead-free RA solder .031" and it works pretty well but I'd like to try the same or something similar in .020"; Kester makes this in a 1lb reel  but I'd like to try it in a smaller package first - anyone know of such a product (Lead Free RA .020 in a package one ounce or less)?  From Kester would be great but I'm open to other recommended brands.

If you're set on Kester 48 broken down into smaller packages, it looks like you'll have to resort to eBay (15ft. of Kester 48, 66 core, SAC305 alloy).

If you can be more flexible on flux, then this might be of interest 2 oz. SAC305, no-clean from SRA.

But why not use lead based solder instead?  It's a lot easier to work with, and it solves tin whiskers (one less thing to chase down  ).

[Electro Fan]

1) Does anyone know if there is a "gullwing" tip for a Weller WESD51 soldering iron?  If not, what would be the next best Weller (WESD51 compatible) tip for SMD drag soldering?

Doesn't appear they make a dedicated tip (gull wing, spoon, ...), but you can use others.

Chisels, hoof types, and knife shapes will all work (just need to develop your technique). Hoof would probably be easiest (they're calling them single flat, such as the ETDD). Between a chisel or knife, the knife should be a little easier IMHO.

Photo of an ETDD (largest hoof offered):

2) I've been using Kester 48 lead-free RA solder .031" and it works pretty well but I'd like to try the same or something similar in .020"; Kester makes this in a 1lb reel  but I'd like to try it in a smaller package first - anyone know of such a product (Lead Free RA .020 in a package one ounce or less)?  From Kester would be great but I'm open to other recommended brands.

If you're set on Kester 48 broken down into smaller packages, it looks like you'll have to resort to eBay (15ft. of Kester 48, 66 core, SAC305 alloy).

If you can be more flexible on flux, then this might be of interest 2 oz. SAC305, no-clean from SRA.

But why not use lead based solder instead?  It's a lot easier to work with, and it solves tin whiskers (one less thing to chase down  ).

nanofrog - Good finds - Thanks!

The eBay Kester solder looks good - I've been thinking about trying that particular version of their products.  Just curious, how many feet do you think might come on the standard 1 lb roll (vs. the 15' which is A-OK/perfect for a trial)?

And thanks for the tip on the ETDD

[nanofrog]

Just curious, how many feet do you think might come on the standard 1 lb roll (vs. the 15' which is A-OK/perfect for a trial)?

~1000ft for .020" of 63/37 (never looked for length on lead-free).

Less dense alloys such as SAC305 will be longer for a given weight & diameter.

[GreyWoolfe]

Finished the second board. It simply flashes 10 LEDs in sequence using a 555 timer and a CD4017 decade counter. The hardest part was the tiny 0603 resistor packs with 4 10k resistors in each one. They are all just wired in series for a total of 200k, but when I tested the series total I got some reading in the 4 Megohm range. The second row had a bad connection to a pad, after touching them up it fixed it. Also had solder bridges on these when installing. Tough and tiny little buggers.

My board arrived today.  Very excited .  Unfortunately, I have a job related repair on my bench that comes first Worst yet, it requires a systemboard that I have to get shipped to me because they are too expensive for us to each stock one.

[xrunner]

My board arrived today.  Very excited .  Unfortunately, I have a job related repair on my bench that comes first Worst yet, it requires a systemboard that I have to get shipped to me because they are too expensive for us to each stock one.

Cool - show us a pic when you are done. And make it a closeup shot - that's what they want to see for scrutiny. 

[xrunner]

Got the Mastech MS8910 yesterday. I really like it - much better than those cheap DMM add-on probes. The sharp tips really make a difference. Not a bad little tester all in all.

[zapta]

Got the Mastech MS8910 yesterday. I really like it - much better than those cheap DMM add-on probes. The sharp tips really make a difference. Not a bad little tester all in all.

I found it to be also useful detecting hidden bridges on smd ICS after reflow. It's easy to touch two adjacent pounds with the tips.

[GreyWoolfe]

Update on my board.  Of course the damn thing doesn't work.  I did a little troubleshooting yesterday and narrowed the problem down to the resistor packs.  I will have to rework them and see what happens.  Maybe tomorrow-too brain fried right now to do more than read posts.

[xrunner]

Update on my board.  Of course the damn thing doesn't work.  I did a little troubleshooting yesterday and narrowed the problem down to the resistor packs.  I will have to rework them and see what happens.  Maybe tomorrow-too brain fried right now to do more than read posts.

Yea those are tiny and I had a hard time with 'em too. Take a break and come back to it tomorrow. 

[tautech]

Got the Mastech MS8910 yesterday. I really like it - much better than those cheap DMM add-on probes. The sharp tips really make a difference. Not a bad little tester all in all.

I got one a good while ago, I was a little disapointed with it compared to the Advanced Devies unit.
Gave it to my best customer as a thank you. 

[GreyWoolfe]

Update on my board.  Of course the damn thing doesn't work.  I did a little troubleshooting yesterday and narrowed the problem down to the resistor packs.  I will have to rework them and see what happens.  Maybe tomorrow-too brain fried right now to do more than read posts.

Yea those are tiny and I had a hard time with 'em too. Take a break and come back to it tomorrow. 

Well, the rework didn't go well.  I ended up removing the 2 problem packs and cleaning the pads.  Upon the resoldering attempt, I first lost a pad then lost the 2nd resistor pack I removed.   Not a problem with the tweezers, just the ham fisted tweezers driver.  No big loss, the price is cheap and it is good practice.  I am going to get another kit and try it again.  At least I will have parts if any go flying!   Xrunner, what did you use to solder the packs?  I used my Hakko 936 with a conical SMD tip and .031" 63/37 Kester 44.  Even with the new and improved glasses and a headband magnifier, it was very hard to see what I was doing.  Those leads are really close together and I'm not getting any younger.

[zapta]

I got one a good while ago, I was a little disapointed with it compared to the Advanced Devies unit.
Gave it to my best customer as a thank you. 

What did you like in the advance devices? What model?

[Mr.B]

tautech recommended the Advanced Devices Tweezers to me...
Ordered on Friday - tracking says they are in NZ now - should receive them tomorrow.

https://www.eevblog.com/forum/chat/what-did-you-buy-today-post-your-latest-purchase!/msg687368/#msg687368

What did I like about them?
Accuracy
Speed
OLED
Apparent build quality. (Will verify when they arrive)

[xrunner]

Xrunner, what did you use to solder the packs?  I used my Hakko 936 with a conical SMD tip and .031" 63/37 Kester 44.  Even with the new and improved glasses and a headband magnifier, it was very hard to see what I was doing.  Those leads are really close together and I'm not getting any younger.

I used a small Hakko (T18 D08) tip and .3 mm solder. It's tough, no doubt.

I got one a good while ago, I was a little disapointed with it compared to the Advanced Devies unit.
Gave it to my best customer as a thank you. 

Well compared to a $300 unit, yea I guess you'd be disappointed.  It's just a hobby, so I draw the line on many expenditures, that little SMD tester is one example. Of course if you want the best go for the ST5S, but for hobby playing around the Mastech works OK and seems to be accurate.

[tautech]

I got one a good while ago, I was a little disapointed with it compared to the Advanced Devies unit.
Gave it to my best customer as a thank you. 

What did you like in the advance devices? What model?

There has been a couple of model changes since I got mine a good few years ago.
I think mine is the original: LR44 x 3 batteries, and side rocker/toggle switch. (STAD ver.3)
Then they offered a rechargable pack with IIRC an inductive charging cradle.

Latest model is a bit different and seems more compact: http://www.advancedevices.com/st5s/
Seems the best priced model is:
https://smarttweezers.3dcartstores.com/Smart-Tweezers-Colibri-PN-ST52CAD_p_73.html

Although is is missing a few features of their other model. 

I've only got the straight tips for mine, I won't use it for PCB population, only component value checks and test. It's much faster than a DMM for simple checks, resistors, diodes etc, although one should always lift a leg for true accuracy.

[miguelvp]

I used my Hakko 936 with a conical SMD tip and .031" 63/37 Kester 44.  Even with the new and improved glasses and a headband magnifier, it was very hard to see what I was doing.  Those leads are really close together and I'm not getting any younger.

Use flux, (flux pen will do) pre-tin one pad, add flux again this time on both pads and place resistor with some light weight on top (from your tweezers) so it doesn't tombstone while you solder the pre-tined one. Then do the other one.

Clean with IPA to get rid off the sticky flux.

Edit: a board holder like the one xrunner used will help a lot, to prevent the board from sliding around while working on it.

[GreyWoolfe]

Xrunner, I am using the same tip, so my choice is good.  Miguelvp, I use MG Chemicals liquid flux through a syringe for control.  I do use a PanaVice to secure the board.  I go flux and tin 1 pad, solder that, solder the opposite pin and then go back and solder the rest.  I also use ipa for cleaning.  Maybe, X's board holder is more suitable as it sits flat on the work surface.  I will have to look into that.  I know there was a post on a new one on the market, I will have to go find it.

[zapta]

It's called stickvise.

[GreyWoolfe]

thanks.

[xrunner]

I'm soldering a "real" SMD kit now. It's a little board I ran across on Ebay that does an FFT on an audio input and displays the results using LEDs. Should be a little fun to see it it works like they claim.

I just need to make a small change. It's designed to accept a stereo input, and it sums the voltages from the L and R on the input plug through two resistors, and does the FFT on the combined audio. However, I'm going to use it on a mono input (using a mono plug) and I don't want the other input from the input stereo jack they supplied to get shorted to ground via the mono plug sleeve, so I will just leave one of the summing resistors off the board. All of this has to be gleaned from the schematic, as they do not supply any instructions whatsoever. 



http://www.ebay.com/itm/131366777479?_trksid=p2057872.m2749.l2649&var=430695780141&ssPageName=STRK%3AMEBIDX%3AIT

[zapta]

What did you like in the advance devices? What model?

There has been a couple of model changes since I got mine a good few years ago.
I think mine is the original: LR44 x 3 batteries, and side rocker/toggle switch. (STAD ver.3)
Then they offered a rechargable pack with IIRC an inductive charging cradle.

Latest model is a bit different and seems more compact: http://www.advancedevices.com/st5s/
Seems the best priced model is:
https://smarttweezers.3dcartstores.com/Smart-Tweezers-Colibri-PN-ST52CAD_p_73.html

Although is is missing a few features of their other model. 

I've only got the straight tips for mine, I won't use it for PCB population, only component value checks and test. It's much faster than a DMM for simple checks, resistors, diodes etc, although one should always lift a leg for true accuracy.
[/quote]

The new ones have very small display. Seems to be a usability regression though I am judging only from the pictures.  I looked at them for some time but the cost will be disproportionally to my hobby needs.

[Mr.B]

@zapta
Being OLED I figured that the contrast should be fairly good, and therefore very readable.
Mine should arrive tomorrow or maybe the next day.
I will post on the display quality.