Multi (more than 2) layer boards

[2camjohn]

Is it possible to do these DIY.

If so are their any websites with guides on it??

Thanks

 

[Nigel Goodwin]

Is it possible to do these DIY.

If so are their any websites with guides on it??

As far as I know they are just thin boards glued together, so to make a three layer board make one double sided, one single sided, and glue them together. Obviously you have to accurate with the registration between the two boards!.

Also make VERY! sure you wash every trace of etchant off the boards - the very first Pace Digital Satellite receivers (exported to South Africa) had a massive failure rate because of that. The PCB manufacturer hadn't cleaned the boards properly, and after a few months the slight traces of etchant between the layers did it's job, and etched through the tracks :lol:

 

[Klaus]

Is it possible to do these DIY.

If so are their any websites with guides on it??

As far as I know they are just thin boards glued together, so to make a three layer board make one double sided, one single sided, and glue them together. Obviously you have to accurate with the registration between the two boards!.

Also make VERY! sure you wash every trace of etchant off the boards - the very first Pace Digital Satellite receivers (exported to South Africa) had a massive failure rate because of that. The PCB manufacturer hadn't cleaned the boards properly, and after a few months the slight traces of etchant between the layers did it's job, and etched through the tracks :lol:

BUT, there's more to it than just gluing two boards together. How would you make connections to the inside layer? They have through plated holes in commercially made boards, a process that most likely would be beyond the facilities of a home PC board constructor.
FWIW, its not worth the trouble for one off boards. Try to stack double sided boards with jumper leads or connectors between them if you are short of room for a larger area board.
Klaus

 

[Dean Huster]

Klaus has about the best answer for this one. Zip back to the 1980s and take a look at PCBs made in the U.S. and those made in Japan. The Japanese were able to make PCBs densely enough that they didn't need to have multi-layer boards when the U.S. had been slaved to them for a number of years. Multi-layer boards in the U.S. have been as dense as 10 layers for computers boards that had the chips populated like cheap housing subdivisions.

And, unless your middle layer is nothing but a ground plane, connections to it would be impossible. I've done the stacked board thing before. It has a lot of advantages over multilayer: cost, ease of construction, ease of repair, et. al. That's where square-pin connectors come in handy.

Besides, multi-layer boards are inherently lower in reliablity than double- and certainly single-layer boards. I've repaired equipment before with three-layer boards where the middle layer had over eight open connections, probably because of a screwed-up manufacturing step where things got contaminated.

Dean

 

[Noggin]

Maybe I'm not thinking of something, but it seems to me that if you drilled a hole through the double sided board, and a hole in the same position through the single sided (third layer), then you could solder a pin to the middle layer, stick it through the first and third layer when you put the two together.

 

[mechie]

Multi-layer boards

I thought multi-layer boards (as opposed to double-sided) were made by 'printing' a copper track pattern followed by a 'mask' layer (a layer of insulating pastic) then another copper track layer :?:

I knew a guy who worked on a Pace decoder production line as a tech, he had the excellent job of fixing faulty boards, DIGGING through layers to find shorts or open tracks and bodging wire jumpers across the holes he had made :shock: -- if this worked the result would be mixed in with the good boards and sold just the same

ps. Noggin long time no see? :wink:

 

[Noggin]

Hahah nope, I havn't been around. Didn't think anyone would notice though, but I suppose this face is hard to forget

 

[samcheetah]

but I suppose this face is hard to forget

:lol: yeah

its not only the face. i also remember your signature.

if im not mistaken the last time i saw you here was when we had a discussion about PICs and AVRs. and you told me about the register to register architechture that the AVRs use.