Double Sided PCBs

Anything to do with our PCB / Engraving machine or software

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nicksmrvil
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Double Sided PCBs

Post by nicksmrvil » Wed 07 Jul , 2010 12:37 pm

Has anyone had any success with this? How do you manage to locate the board precisely when you flip it to machine it on the other side?

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Steve
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Re: Double Sided PCBs

Post by Steve » Thu 08 Jul , 2010 9:04 am

I have made some double sided boards but they were fairly simple with thick tracks for power.

The most important thing to do is ensure your board is cut exactly square and true.

Then you need to ensureyou mount it square to the axes and know exactly where the datum is.

If you have a PCB engraver fasten down a fixture first. Then write a program to engrave a rectangle the exact siz of the board on the fixture.

In the PCB software ensure the board size you use is exactly the same as the actual coper board.

Stick down the board and cut the first side.

Then flip the board either vertically or horisontaly and stick down within the same marked box on the fixture then do the same with the gerber image in the software.

The accuracy of the cut board and the positioning of it on the fixture will deturmine how good the finished part is. A 0.5mm error in positioning will result in a 1mm error in the finished part which with fine tracks is a major issue.


Another tip i would give is that if the tracks are being used as Vias to connect the two layers together you have to both top and bottom solder the joints It is probably worth adding dedicate vias as well so a piece of tinned coper wire can be fitted.

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