SMD and shaky hands - please help. - Page 1
Forum section: electronics / general

author: FriedMule
author_rank: Frequent Contributor
timestamp: January 21, 2022, 09:15:32 pm
content: SMD is the future and is nice when space is sparse, but when your hands are more geared toward making milkshakes than SMD, does it really get frustrating!!I have tried to steady my hand on the other hand and on something study, and it helps a lot, but gets frustrating in the long run.There is always the solution to sell my kidney and get a pick and place machine ($2000 - $60,000) but to be honest is that more than all my gear in my entire lab costs, combined.Isn't there some cheaper solution, maybe even to 1206 and 0204 components?

author: jpanhalt
author_rank: Super Contributor
timestamp: January 21, 2022, 09:30:14 pm
content: For 2-lead components, I use a microdot of medium (or old thin) CA adhesive. That gives plenty of time to adjust. Then press with a thin piece of piano wire as a spring and wait a little bit. Once the CA is set, soldering is easy. Some here think that is crazy, but it works and does not affect any of the device's electrical characteristics within measurable limits. Soldering temps generally cause the CA to decompose. It is never a problem to remove such components.

author: FriedMule
author_rank: Frequent Contributor
timestamp: January 21, 2022, 11:01:01 pm
content: Sounds really great, may I please ask you to elaborate some more, I am not sure if I completely understand?

author: Renate
author_rank: Super Contributor
timestamp: January 21, 2022, 11:04:36 pm
content: I stick to 0805. I use a little jig with a paper clip to push down on components. I put pen flux on first, tack one side, do the other side, then finish up the first side.

author: FriedMule
author_rank: Frequent Contributor
timestamp: January 21, 2022, 11:10:39 pm
content: But how do you get the component from outside to the correct placement on the board? To me, is it like placing a dot on a random orbital sander:-)

author: vstrulev
author_rank: Contributor
timestamp: January 21, 2022, 11:38:47 pm
content: Cheap solution, which I think would satisfy your needs, would be something like this(we did it few years ago):

author: jpanhalt
author_rank: Super Contributor
timestamp: January 21, 2022, 11:39:59 pm
content: Quote from: FriedMule on January 21, 2022, 11:01:01 pmDescribed in more detail here:https://www.eevblog.com/forum/beginners/surface-mount-soldering/msg1134290/#msg1134290The wire is about 1/32" diameter (0.030").I've used either technique for years. For a few pieces, I use the pre-tinning method. For lots of chips, I use the CA. I tend to limit myself to 805's, and very rarely 603. Nothing smaller.

author: thm_w
author_rank: Super Contributor
timestamp: January 22, 2022, 12:29:21 am
content: Quote from: vstrulev on January 21, 2022, 11:38:47 pmThey have ones that just have foam pads to rest your hand on, then pick and place with tweezers.But the camera here is a really nice addition.Commercial model is ~$2k:https://uk.farnell.com/cif/v900121/manual-pick-place-station-easyplacer/dp/2468767

author: DLE
author_rank: Contributor
timestamp: January 24, 2022, 08:37:26 pm
content: I've thought about buying 2 sets of linear rail guides, like the ones below and making a simple XY table to rest my hand on. Small boards aren't a big deal but dealing with larger boards where it's hard to rest your hand and place parts out in the middle I think this would work well. But haven't found enough need + time to build one yet though so mileage may vary.https://www.amazon.com/Mssoomm-Linear-Bearing-Motion-Aluminum/dp/B08YQX253W

author: Gyro
author_rank: Super Contributor
timestamp: January 24, 2022, 09:15:08 pm
content: What are you using for magnification? I have shaky hands but find that the shaking decreases significantly when using my binocular microscope.

author: jpanhalt
author_rank: Super Contributor
timestamp: January 24, 2022, 10:08:47 pm
content: I agree, getting a part onto a board with paste could be difficult. With the method mentioned before, I can get the part approximately right, then push it around with the same needle I use for CA.I also find hand and arm position are critical. Sometimes, using one hand to steady the other helps. Lots of workarounds, I am sure. I use a head mounted magnifier too.

author: m98
author_rank: Frequent Contributor
timestamp: January 24, 2022, 10:58:53 pm
content: Some general tips:Lighting. You might think your workbench is well lit, it probably isn't. Make sure you have at least 1000 lux.Ergonomics. Watchmakers have dealt with miniscule parts for centuries, look how they sit at their workbench. The workbench should be almost at shoulder height, so your whole body and arms are stabilized, and all fine movement can come out of your wrists and fingers.Magnification. The finer visual feedback you have of your hand's position, the less it shakes. Get a decent head-mounted loupe, or even a stereo microscope.

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: January 25, 2022, 04:49:47 am
content: Oh man that's one of the things I am afraid of happening in my retirement years D:My old work had a hand assembly SMD/SMT jig, don't recall the exact model but it was something like theFRITSCH LM900Idea is that you rest your arm next to the PCBs and then use the nozzle to pickup components from tape or the big central wheel. You could also rotate the components which was usefulNot sure if this could help? Also here it is in action, I know that the one we had was no where as fancy as this, just had the big wheel, tape dispenser and the vac nozzle

author: HB9EVI
author_rank: Frequent Contributor
timestamp: January 25, 2022, 10:05:10 am
content: I second Gyro's point. I have medication induced shaking of the hands, and it's easier to handle that with magnification; so far I get along using a magnification lens implemented in my bench's working lamp only. The next most obvious step is a binocular.

author: KaneTW
author_rank: Frequent Contributor
timestamp: January 25, 2022, 10:25:32 am
content: I have the fine motor skills of a wet potato and it's fine under a binocular microscope.

author: IconicPCB
author_rank: Super Contributor
timestamp: January 26, 2022, 10:53:53 am
content: Simplest way is to get yourself onto beta blockers.Simplest way to get beta blockers is to get a heart attack.

author: gnuarm
author_rank: Super Contributor
timestamp: January 26, 2022, 02:51:57 pm
content: Quote from: FriedMule on January 21, 2022, 11:10:39 pmI had that problem about 20 years ago. I have intentional tremor which is natural, not medicine related... unless they are giving me meds in my food!I remember assembling a tiny board (about 3/4 inch by 3/8 inch) with 0603 components. Some of them took about 20 tries before I was happy with the result. I would use a toothpick to move the part in place, repeating it several times to get it right. Then I'd bring in the soldering iron and watch it move off the pad or pads. The wet solder making the part stick to the iron didn't help.After that I found a really neat solution. Contract assembly houses. Yup, I don't solder anything smaller than... well, I don't solder at all I guess. I design products and let others do the soldering. I can still manage to probe a circuit, but often let someone else do that as well. I try to deal with more managerial duties now.

author: gnuarm
author_rank: Super Contributor
timestamp: January 26, 2022, 02:53:59 pm
content: Quote from: jpanhalt on January 21, 2022, 11:39:59 pmI don't know why people have to use obscure abbreviations. Is "CA" contract assemblers?

author: jpanhalt
author_rank: Super Contributor
timestamp: January 26, 2022, 03:15:16 pm
content: CA = cyanoacrylate adhesive. Very widely used in the US. Even Wikipedia lists a subject matter page for "CA glue." Had you clicked on the link, it is described there. In the context of my comment, I have a hard time visualizing a microdot of a "contract assembler."

author: SMTech
author_rank: Frequent Contributor
timestamp: January 26, 2022, 03:31:27 pm
content: Quote from: jpanhalt on January 26, 2022, 03:15:16 pmSuperglue to its friends. I honestly don't understand this technique, I'd make a huge mess and glue my tweezers together but maybe that's just me. Regardless of your motor skills the best way to steady your hand is definitely firm support at the wrist and short of a very elaborate setup that makes anything but small assemblies very difficult to work on by hand. Magnification is good but adds a different challenge with field of view & perspective. Mechanical aids like are nice but that CIF example is actually quite cheap compared to the Fritsch version and at that point, a slightly crappy pick n place from China is probably going to be better.There other solutions of course, do all your projects using modules from the world of Arduino, someone somewhere has slapped pretty much anything you could want onto an easily used, breadboard/featherboard/HAT friendly little board, if and when it's time to go commercial - get someone else to do it.

author: asmi
author_rank: Super Contributor
timestamp: January 26, 2022, 03:35:42 pm
content: Once I bought stereo microscope, I found that my hands are capable of much finer movements when I can actually see what I'm doing. So now I just can't imagine soldering anything - big or small - without a microscope. This is the second best investment you can make to improve your soldering experience - right after buying quality soldering iron (ADS200 FTW!!). Nowadays you can buy a good stereo microscope for US$150-200.

author: jmelson
author_rank: Super Contributor
timestamp: January 26, 2022, 05:02:35 pm
content: Quote from: gnuarm on January 26, 2022, 02:51:57 pmDon't be sure they aren't. God only knows what is in our food these days.QuoteI use bent-nose tweezers, and rest the heel of my hand on the work surface. Observe through stereo microscope. Place a dot of solder on one pad of component position of board, place part and hold with tweezers while soldering that pad, then solder remaining pad(s). Solder won't stick to stainless tweezers, but the flux will, and makes them a bit sticky. I've used this technique for 30+ years and it has worked quite well. I now do all production work with a P&P machine and homemade reflow oven, but still do one-offs and repairs this way.Jon

author: gnuarm
author_rank: Super Contributor
timestamp: January 29, 2022, 11:49:55 pm
content: Quote from: jmelson on January 26, 2022, 05:02:35 pmI hope you are kidding. Science is not able to find every last cause and effect such as exactly what chemicals cause cancer in humans and which don't. But if there is any significant impact and it were caused by something in the food, it would become very apparent what was causing it.QuoteThanks for the advice, but the sort of electronics I would be designing requires reflow for soldering the chips (like BGAs) so no reason to worry with soldering the parts I might be able to do if I were to work at it.

author: gnuarm
author_rank: Super Contributor
timestamp: January 29, 2022, 11:56:30 pm
content: Quote from: jpanhalt on January 26, 2022, 03:15:16 pmThe quote I cited wasQuoteCA was an obscure reference. I don't see why I should have known to check with Wikipedia for "CA glue" in this context.I'm just trying to explain that your use was not clear to me and that it is a good idea to not abbreviate everything if you wish to be understood. I figure if what I'm writing is worth saying, then it is worth making enough effort to be understood.

author: rfclown
author_rank: Frequent Contributor
timestamp: January 30, 2022, 01:30:35 am
content: Stereo microscope and good fine curved tweezers. I'm 60, don't have the steadiest of hands, and my prefered parts size is still 0402. I hate doing 0201, but I can. I have Bauch & Lomb stereo zoom 4s. You can get them on eBay for < $200. Fluorescent ring light. Metcal iron with fine tip. Put solder on one pad, hold part with tweezers and solder that one pin. then solder the remaining pins. Use fine solder. I have a 1 lb roll of Kester 44 63/37 0.02 in diameter that hopefully will last me forever since I detest lead free.Stereo microscope, good light, good fine tip curved tweezers, fine leaded solder, good iron (I have Metcal) with fine tip. If I'm missing ANY of these I can't do it. But with ALL of these items I can. Hand shaking does make 0201 frustrating.

author: doppelgrau
author_rank: Contributor
timestamp: January 30, 2022, 10:56:53 pm
content: If you have a unused 3d printer, you might try to convert it to a simple PNP with OpenPnP and "LoosePartFeeders" (or HeapFeeder) for passives and strip Feeder for rest.

author: Brage
author_rank: Contributor
timestamp: February 05, 2022, 10:47:17 pm
content: I had that machine at my old work. Highly recommend it if you can afford it.Don't need all the bells and whistles, though. Ours had most of the stuff shown in the video, except the flipper. Did not really use any of it other than the placement arm itself. A piece of sticky-tape to stick down the components, some good lighting, and taking it slowly.A more budget solution, like the videos shown, might do the same job. I'd get a good mechanism for rotating (yaw, about the z-axis) the components after you have picked them up.

author: tooki
author_rank: Super Contributor
timestamp: February 26, 2022, 10:53:49 am
content: Quote from: Gyro on January 24, 2022, 09:15:08 pmThis. I cannot emphasize enough how much of a difference it makes.