What did the manufacturer mean by asking if an angle should be made for the fingers?

Question

I sent in Gerber files designed by someone else to PCBWay. It's a cartridge for a Commodore 64.

They responded today with this question, and I'm not 100% sure what they are asking.

Ref attached screenshot, please advise if we should do 30° degree for finger places. If yes, we will chop copper to reach 1mm distance from copper pad to outline.

When I loaded the design in EAGLE it did say that the card edge connector pads were too close together. Do they mean 1 mm distance between the 'fingers' or 1 mm distance between the 'fingers' and the board edge?

I know it's a 50/50 chance whether I say yes/no, but I'd like to be correct. It's weird, because the person who designed this said he had no issues getting it made.

Nice to see that somebody at PCBWay is actually examining and reasoning about individual submitted designs. Plenty of low-cost fabs wouldn't bother. — Sneftel, Apr 24 '18 at 15:02
I bet they meant to write "30° bevel" because the word degree repeats the ° — dlatikay, Apr 24 '18 at 18:30
Yes, I was quite surprised that they asked me. For the cost, I was not expecting that service. — Oggie, Apr 24 '18 at 19:54
PCBWay just got me as a customer. Thanks for letting us know. — dotancohen, Apr 25 '18 at 19:04

score 58 · Accepted Answer · answered Apr 24 '18 at 12:33

58

When they say 30° degree, I think they mean to chamfer the end of the edge connector for easy insertion into the C64 cartridge slot.

When they do that, you will probably lose the last mm of copper on the end of the fingers.

If they do this free of charge, I see no reason not to say yes please.

Image from http://www.industrial-electronics.com/et-4e_14.html

answered Apr 24 '18 at 12:33

Dampmaskin

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that makes complete sense now. I never even thought about the beveled edges. Thanks! – Oggie Apr 24 '18 at 13:13

score 36 · Answer 2 · answered Apr 24 '18 at 12:36

36

It is my understanding that they are asking if you want them to bevel the PCB where the connector is located.

Here is an illustration from Eurocircuits demonstrating the end result:

If you look at other card edges you will see that they are almost always beveled.

answered Apr 24 '18 at 12:36

pipe

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Just a note you and the above answer made me look up the difference between "chamfer" and "bevel", I think it's technically a "chamfer" but the difference matters little. – Sam Apr 24 '18 at 20:57
@Sam I've always assumed that a chamfer is always at a 45° angle because of the symmetry, maybe it's not as strict of a definition. – pipe Apr 25 '18 at 05:22
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@pipe if you look at mechanical standards then youll se that they use chamfer for other than 45 degree angles also. – joojaa Apr 25 '18 at 05:47
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If it has an edge that is at a 45-degree angle, then it is a chamfered edge. If it is an edge that isn’t perpendicular, doesn’t come to a sharp point, and isn’t at 45 degrees, then it is a beveled edge. – [ELU](https://english.stackexchange.com/a/403151/68817) – Mazura Apr 25 '18 at 23:14
Bevel vs Chamfer: https://www.sansmachining.com/whats-the-difference-between-bevel-and-chamfer/ – PStechPaul Aug 05 '22 at 06:49

What did the manufacturer mean by asking if an angle should be made for the fingers?

2 Answers2