Home brew multi layer PCBs?

Discussion in 'General Electronics Chat' started by spinnaker, Feb 8, 2011.

  1. spinnaker

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    Oct 29, 2009
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    I just say a post that showed what looked like a multilayer PCB. Can this be done at home?

    Obviously I am not ready for this level of complexity so I don't need a lot of detail. But can someone explain the basics of how this would be done?

    And how are vias done? I have read about them and I was curious of how they would be installed.

    Again just the basics. As we old folks would say "the nickel tour". :)
     
  2. nerdegutta

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    Dec 15, 2009
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    I made a double sided PCB once, with the UV-light exposure method. I found the hardest part was to align the to trace-transparent. I did not drill alignment holes, or scotch tape them together. SO it was a bit off course.

    For vias, I drilled 0.7mm holes, and used cut-off from components and LEDs.

    To make a homebrew multilayer, I think I would use thin single layer, and glue it on top of each other. Not sure, but I would take it from there...:)
     
    Last edited: Feb 9, 2011
  3. thatoneguy

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    I'd suggest sending out to a board house. Not worth the huge hassle, though some have done it using the "scissor cut" thin PCB, the inter-layer connections (vias) would be the major pain.
     
  4. Wendy

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    Mar 24, 2008
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    That is what I was thinking. There is no practical method for making vias, the tube that interconnects all the layers. With 2 sided boards you still have to solder the top and the bottom, how would you connect to a middle layer?
     
  5. AlexR

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    Jan 16, 2008
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    Double sided is relatively easy and I have made double sided boards at home without any drama. You can use component leads to interconnect the top and bottom layers or when a via is hidden under a component you can use special ferrules that are made for the job. More than 2 layers however is not something you could (or for that matter would want to) do at home. Apart from the problem of aligning and bonding the multiple board multiple layers there is the problem of creating plated-through holes and vias to connect the inner layers to the outside world.
     
  6. shortbus

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  7. spinnaker

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    I see how double sided would work. I was more interested on how someone would do more than 3 layers.
     
  8. Wendy

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    A lot of it is specialized plating technology. I really don't think any home setup is going to do 3 layers, by the time you create that much hardware you are doing it for a business.

    Have you made a 2 layer board before? How did you connect the top and bottom layers? This is core to the problem.
     
  9. spinnaker

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    No like I wrote in my OP. I have not even done double sided yet and probably no time soon. I was just curious.

    Also curios about vias for double sided but I see it is pretty low tech from a hobby standpoint.
     
  10. thatoneguy

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    I remember seeing a "via kit" for sale somewhere, can't recall or find the site right now.

    Basically, they were vias of various diameters, and a punch sort of device to "rivet" the via to the board. They substituted for a "plated thru" hole as well. I don't think they were very cheap, and targeted toward dual sided boards.

    --ETA: Found it
     
  11. jpanhalt

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    Jan 18, 2008
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    Circuit Technology Center (Haverhill, MA) made the little repair kits you talk about. It seems the company has changed direction a little to actually doing the repairs on site. However, this page still has the rivets. They work OK and are quite flat to the surface, so you can mount components over them, if need be.

    If you have minimal machining tools, all you need is the rivets. I made my own dies and used a small arbor press for installing them.

    John
     
  12. Wendy

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    When I worked for Collins Radio in the early 80's that was something they used. I never really liked them though, because you had to solder the "rivet" to the board pad or ground plane. The rivets were a little old, so they didn't always solder well, and now you had an open in the circuit.
     
  13. thiagokunz

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    Jan 26, 2014
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    This video can show how it is made in big companies. First you etch the inner layers. Then drill. Then apply a thin layer of conductive polymer by electrolytic batch, and another electrolytic batch to add copper over this first layer. Then the outer layers are sandwiched with the inner layers...

    http://www.youtube.com/watch?v=sIV0icM_Ujo
     
  14. spinnaker

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    Why do I smell spam? A link posted by a new forum member with only one post. Anyone have a quarantine VM or PC that would like to try the link?
     
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