Multilayer DIY Printed Circuit Boards

[Frantone]

A new thread By Request!  Enjoy!



To create the CuteUino prototypes I had to push the absolute limits of DIY printed circuit board density.  In the final assembled form these raw circuit boards produce two different three-layer PCB's just 20mm square, and all hand made.  Now, that is very small... and very cute indeed!



To make hand made three-layer PCB's I made a sandwich of two single sided boards that would be aligned with the headers, and a copper foil inner ground plane layer was hand cut and soldered into the vias.

   

  My three layer hand made PCB package with lots of vias.



http://www.frantone.com/designwritings/design_writings.html#cuteuino

[Rerouter]

give it 2 months and i envision a video from you on a DIY IC package at this rate 

great work as usual fran,

[Kremmen]

 

[peter.mitchell]

TBH, im also quite impressed at how nicely the text "CuteUino " in the pour turned out

[poorchava]

That works. I have made 4 layer boards in the past. Just etch different layers on single side laminate, solder header pins, second layer, solder header pins and so on. The problem is the meniscus which forms around the header, which causes a gap between laminate layers. And having a cnc-drilled holes helps. It's actually best to drill a stack of raw laminate plates to maintain perfect hole alignment.

[Rerouter]

poorchava could you not technically get away with some low melting point solder paste or similar for hard layer to layer construction? using solder mask to leave only your pasted vias touching?

[ecat]

Nicely done Fran. Sweet little USB I/F idea too.

I suppose it is actually quicker and easier to use copper foil vs etching a double sided + a single sided board. Which gives me an idea (don't laugh, it's in a strange place):

If you cut the two tabs you are soldering to about 3 times longer, you can place the two boards together, wrap the tabs 180 degrees around to the bottom board and then do the soldering. No more solder joint between the boards But may need a dab of nail varnish to ensure the wrapped copper doesn't get torn away.

[SeanB]

To handle the solder bump just back drill the upper layer of board to provide a place to put the solder joint. Only needs to be done on a few holes in this case, and then they will be flat.

Very nice Fran, you are making a replacement for an old IBM mini look there, just need to get a stack of the aluminium cans that were used on the IBM logic, and a board with lots of via's on top and bottom in a pattern, then you can build IBM style.

[Frantone]