Need Help, How to create gerber for this PCB - Page 1
Forum section: electronics / general

author: glicos
author_rank: Regular Contributor
timestamp: August 12, 2017, 02:57:33 am
content: I have a PCB for reverse engineering. Attachment 1 is the actual PCB and 2 is the 3D representation of the PCB. The problem i have is the edge fingers are not placed at the bottom portion but on the inner (1mm from top layer) and a 0.6mm deep slot is created from the bottom layer to access the edge fingers (total thickness is 1.6 mm).I already created the Gerber of this PCB (3,4,5) but said edge is on the bottom.. I also attached the 3d in the PDF fileAny feedback will be highly appreciated...

author: janekm
author_rank: Unknown
timestamp: August 12, 2017, 03:10:15 am
content: You'll need to talk to the PCB factory. This is a really unusual configuration with the milled slots on only some layers. Off the top of my head I can't even work out what layer stack up would work for this.

author: glicos
author_rank: Regular Contributor
timestamp: August 12, 2017, 03:16:00 am
content: Quote from: janekm on August 12, 2017, 03:10:15 amThanks for the reply janekm. I presume this is specially manufactured PCB. Maybe after the 1mm thick PCB is fabricated (complete with trace), then some sort of FR4 and prepeg with 0.6mm thicknes is added on the finished PCB at the bottom. Don't know..maybe..

author: ataradov
author_rank: Super Contributor
timestamp: August 12, 2017, 03:47:27 am
content: Does it look fully laminated from the edge? It look like the easiest way is to make base PCB and the top one separately and then just glue them using conventional glues (not a full PCB process).Gotta be very expensive and labor intensive.What it this from?

author: janekm
author_rank: Unknown
timestamp: August 12, 2017, 05:29:07 am
content: Quote from: ataradov on August 12, 2017, 03:47:27 amThat's kind of what it looks like to me too, because I imagine trying to mill just one prepreg & FR4 sheet together would be messy.For prototyping I would make the two parts separately, as regular 2-layer PCBs, with alignment holes for some dowel pins and glue it with regular adhesive as you suggestedWhich a PCB factory should be able to do for you too... the challenge is just documenting exactly what you want done. In terms of file exchange, you would typically put that information on a documentation layer (but also point it out in email during the RFQ process so it's not overlooked).

author: Rerouter
author_rank: Super Contributor
timestamp: August 12, 2017, 05:39:28 am
content: If your volume is low, i would agree with the 2 pcb approach, make your main PCB to the thickness of the fingers. copy the project so all your holes are aligned. and make a second for the remaining thickness, specifying no soldermask on the 2 surfaces to be joined, you would then glue these 2 together,For middle volume, same deal, but you could likely get them hot pressed together still at the factory, as its not too different to how buried via boards end up being built.

author: ataradov
author_rank: Super Contributor
timestamp: August 12, 2017, 05:46:52 am
content: Quote from: Rerouter on August 12, 2017, 05:39:28 amIt is somewhat different. With buried vias you don't need to worry about glue getting on the open space. In this case you need to be careful to preserve the gold fingers.