Limits on flexible PCB dimensions?

Discussion in 'General Electronics Chat' started by John P, Nov 12, 2013.

  1. John P

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    Someone on another thread mentioned this circuit board manufacture service:
    http://imall.iteadstudio.com/open-pcb/pcb-prototyping.html

    If the boards are so cheap, I was wondering about using flexible PCB's to replace small modules connected with wires. What I'd want to do would be to have little rectangular nodes with a few components on them, and then have a very narrow neck of flexible PCB maybe 2 or 3 inches long connecting to another node. This "neck" would need to be no more than 1/16 inch wide (1.5mm, if you don't like medieval units) and would need 4 electrical traces running between the nodes, 2 on each side of the PCB. I imagine that etching this type of board would be easy enough, but cutting it out might be problem for the manufacturer. Does anyone have some knowledge of how a board like this would be made, and what the limits on dimensions might be?
     
  2. ronv

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    Probably laser cut from the Gerber files.
     
  3. ErnieM

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    Just looking at the sample image on that site you can see they seem to have no problem making convoluted edges seemingly at random. If I was looking to get a flex board I really wouldn't care how they do what they do, that's their job.

    MY job is to define the outline shape. With fixed PCBs (I've made many but zero flex) the shape is fdefined by a gerber layer named "outline.gbr" or such. That's always got my point across
     
  4. mcgyvr

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  5. ronv

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    With a regular board they can route it, but I don't think they are going to make a die for a run of a few parts. I still got my money on laser cut.
     
  6. mcgyvr

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    from the last slide..

     
  7. ronv

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    Mmm, sorry I was just looking at the pictures and can't imagine them making any kind of die for $65 and trying to route kapton in that kind of shape might be tricky.
     
  8. John P

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    Thanks for the replies.

    Yes, I assume the boards are cut by laser, which shouldn't be difficult given the thickness. But my question would be how they assure that very narrow sections stay straight and flat while the cutting is done, because if the material wanders around during the cutting process, it will never come out accurate. Maybe I should email them and ask.
     
  9. GopherT

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    It may be held down with a vacuum table - like an air hockey table with the fan reversed.
     
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