Please bear in mind that the overall reliable quality of the process and low price usually means that it is cheaper to replace with a new board rather than repair the board.
Failures are infrequent, and rarely obvious.
And getting chip resistors and so on without a spec or data sheet is also an issue.
And some Class D chip amps are thermally bonded to the boards, making replacement difficult.
Add to that frequent changes in firmware, then it is impossible to repair a 4 year old board, the replacement is as low as $1 at times.
Wil you bother to repair a $10 item?
New builds...how many kids get out of their phones to learn anything?
If all the farmers become zombies, we will surely starve!
Failures are infrequent, and rarely obvious.
And getting chip resistors and so on without a spec or data sheet is also an issue.
And some Class D chip amps are thermally bonded to the boards, making replacement difficult.
Add to that frequent changes in firmware, then it is impossible to repair a 4 year old board, the replacement is as low as $1 at times.
Wil you bother to repair a $10 item?
New builds...how many kids get out of their phones to learn anything?
If all the farmers become zombies, we will surely starve!
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I use this same technique to place 0.5 mm lead pitch microcontrollers. Works exceedingly well. I use a bit of flux remover afterwards to clean the board up and I then check the solder job with a loupe. I very rarely have to go back and resolder any pins.
I have not tried the glue+solder paste + heatgun method yet. I think that approach will give a better looking mechanical job. I use needle point tweezers, 0.5 mm solder and a needle point soldering iron bit to place discretes and small signal devices and opamps.
I prefer working with SMD - luckily I have a steady hand and my spectacles are good.
Funny, 35 yrs ago when I worked in product development the others guys in the lab nicknamed me ‘SMD Eyes’ - the SMD devices then were much bigger but I could easily read the code on the mini-melfs, check for mis-soldering etc.
My employer stepped out of TO-92 in 2007. The company had already started obsoleting leaded devices before that. It’s hard to believe, but in 2015, we were shipping 70 billion small signal discrete devices a year - no through hole and had about 25% volume market share. Rohm we’re always number one and shipped a few billion more a year. Year on year volumes did not decline as predicted years before that with the arrival of more integrated solutions. As more and more electronic devices (phones, consumer electronics, computers etc) came to market, there was a huge general increase in discrete device demand. Diodes, TVS, 2N7002 and BC8xx were big volume movers.
When you see this, and the general trend to smaller end equipment you can see why most companies have stepped out, or are stepping out of leaded packages.
I scouted and found many solder solution adapters, I also found an Altium file on pcbway community with a scored card layout, 8 leg SOIC to DIP. I have not been looking forward to it but it is probably time to wade through some utube videos and see all the above in practice, or attempted practice,
I fail to see the higher initial expenditure. A soldering pencil costs as much as a soldering iron. Solder is priced by weight, so no difference there either. If you go the reflow route, you'll need a toaster oven ($10 at your local thrift store) and a good pair of tweezers. Maybe a magnifying hood, depending on your eyesight. We're talking maybe $50 worth of stuff if you're reasonably frugal. $100 if you're not. That doesn't strike me as an overwhelming amount of money to spend on tools. Heck those Lindström pliers probably set you back that much.
If you already have a PTH setup all you need is a fine tip for your soldering iron ($5), a good pair of tweezers, and maybe that magnifying hood.
I found SMD parts a bit intimidating too until I actually tried soldering them. Now I prefer them over PTH parts. There're no component pins to cut. No mess. Just apply the solder paste through a stencil, place the parts, and stuff the board in the E-Z Bake oven. 10 minutes later: Done!
If anything I would argue that SMD assembly has a bit higher recurring cost due to the cost of the stencil. OSH Stencils is great and their stencils are very low cost, but I often want them delivered within a reasonable amount of time, so I spring for the FedEx shipping which costs more than the stencil. If you're more patient than I you can shave off some cost there.
Tom
And i see it not being mentioned, smd parts take A LOT less space in workshop 😁 Atm, only big boxed stuff in my space are boxes of capacitors those are still better made in TH, and are more veraatile as can be laid down. I literally have thousand smd resistors in a matchbox size container 😅 One thing though is what i recommend to everyone, use silica packs in storage with your smd components. Especially so if you do reflow.
Buy 10 or 20 of the cheapest chips and resistors you can find and some adaptor boards and practice.
I'm 67. Mostly it's not too difficult. I use a pair of 4.0 reading glasses + a bright light, non magnetic tweezers, fine solder and relatively fine conical (not needle) tip. Wipe the pads with solder, brush over liquid flux, position chip, use a cocktail stick to hold in place, touch one leg/pad with the tip enough to melt the solder, then do the rest if you're happy with alignment.
Practice, practice, practice and don't do too much in one go.
I'm 67. Mostly it's not too difficult. I use a pair of 4.0 reading glasses + a bright light, non magnetic tweezers, fine solder and relatively fine conical (not needle) tip. Wipe the pads with solder, brush over liquid flux, position chip, use a cocktail stick to hold in place, touch one leg/pad with the tip enough to melt the solder, then do the rest if you're happy with alignment.
Practice, practice, practice and don't do too much in one go.
You can get away without stencils for larger sizes, ie down to about 0805 and SOIC, I use chipquik syringe for dispensing paste in that scenario, which is a bit fiddly but doable.
For 0.65mm pitch or less stencils become pretty-much required to avoid the risk bridging.
For 0.65mm pitch or less stencils become pretty-much required to avoid the risk bridging.
So that's it, stencils and solder paste. I've done "regular soldering" with SOIC, but smaller things (SOT363 diode arrays) I've yet to solder without having something shorted, including trying to fix it with solder wick.
OTOH I hear PCB makers will stuff a board for not too much money.
OTOH I hear PCB makers will stuff a board for not too much money.
To me, the main disadvantage of SMDs is that they are less suitable for mounting on perfboard or in dead bug style on a piece of copper-clad board. That can be solved with adapter boards, though.
Other disadvantages are that the value is not printed on ceramic capacitors and that there are no coloured bands on ordinary resistors (no technical issue, I just like the colours), although that is solved when you use MELF resistors. I also haven't a clue how to calculate if power devices are adequately cooled when there is a whole bunch of them using the PCB for a heatsink.
Other disadvantages are that the value is not printed on ceramic capacitors and that there are no coloured bands on ordinary resistors (no technical issue, I just like the colours), although that is solved when you use MELF resistors. I also haven't a clue how to calculate if power devices are adequately cooled when there is a whole bunch of them using the PCB for a heatsink.
Jlcpcb for example, depends. If it's one sided or double sided assembly (prices are jumping drastically), if components are in stock or not, also if the components required are considered regular (not swapped on machines, do consider most are not regular and are charged per item/roll swap). For hobby use, it can turn out not so cheap 🙂
Also, you don't HAVE to go for the smallest. I have zero problems soldering the tiniest stuff, but I always advise people just to go for like 1206 or 1210 instead.
At that size you're basically not that much smaller as some through hole components.
These days I often just get things assembled as well, it's so cheap.
True. I hand solder down to 0603 using a soldering iron and 0.5 mm diameter solder. If I did that every day I'd buy a roll of thinner solder ... and a dissecting microscope.
If I'm just populating a few parts or doing a bit of repair/rework, I won't bother with a stencil. But if I'm populating an entire board I'm definitely using a stencil. My neck and upper back thanks me for that. 🙂
Tom