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PCB Suggestions from an old fossil
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PCB Suggestions from an old fossil

by Repairtech on Fri Feb 26, 2021 11:59 pm

After reading through this forum I would like to respectfully submit a few suggestions that might make fabricating your own PCBs a bit easier. Always keep things as simple as possible. I don’t suggest all of these items will be appropriate for you but it is just a starting place. First I find no lead content solder harder to use in some cases, so only use it if it is absolutely (I have used leaded solder for nearly 60years and I am not dead yet).
I make most of my own PCBs using laser printer, a laminator and etch them with a mixture of hydrochloric acid and hydrogen peroxide for enchant. Make sure you use gloves and about a 1” x1” square sponge soaked in etchant, dragging your sponge across the board gently to remove board smut from the board. With a bit of practice you can have 10mil wide traces with a 10 mil spacing and etch a small 3 x2 inch board in less than 2 min per side. I also use home made electro less tin plating. I make the tin plating solution using two pieces of “modern pewter” which is usually between 92 & 97 % tin. Connect 3v to the each piece of pewter an put into wide mouth glass jar filled with distilled water and a tablespoon of table salt and when water turns reasonably dark green you are ready to put your pcb in. I am old school I use 63/37 tin lead solder and Kester 1544 flux. After board is cleaned with 91% grain alcohol (also good to drink sometimes too) I test the board is working correctly then give it a couple coats is spray shellac. I do this because many of my projects are used outside. Oh. If components and board lands are not bright and shiny I use a pencil eraser or if it’s really bad some scotchbright to clean them but easy does it you don’t want to remove the tin plating.

Hope this has helped someone

Leo

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Re: PCB Suggestions from an old fossil

by dastels on Sat Feb 27, 2021 11:35 am

That brings back memories. I was doing this back when I got started in the '80. These days it's as fast and a lot easier, cleaner, and pretty much error-proof to order your boards from OshPark or Aisler, etc. Plus you can get multilayer with plated holes/vias. I remember the arduousness of making double sided boards by hand. SO I guess they weren't all good memories :)

Dave

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Re: PCB Suggestions from an old fossil

by jps2000 on Sat Feb 27, 2021 11:56 am

Of course ordering boards is nowadays quite easy and cheap. In particular if you need double sided boards.
But small single sided smd boards I still make as described above. It takes just an afternoon to try out something. Many circuits can be made single sided with just a groundplane.
The use of green coating flux sprays gives a semiprofessional appearance.

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Re: PCB Suggestions from an old fossil

by dastels on Sat Feb 27, 2021 12:38 pm

I see desktop milling being used with good success for making single sided boards. Neither milling nor etching are very apartment-friendly, however.

Dave

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