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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.

Board in question

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.

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    \$\begingroup\$ Nice to see that somebody at PCBWay is actually examining and reasoning about individual submitted designs. Plenty of low-cost fabs wouldn't bother. \$\endgroup\$
    – Sneftel
    Commented Apr 24, 2018 at 15:02
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    \$\begingroup\$ I bet they meant to write "30° bevel" because the word degree repeats the ° \$\endgroup\$
    – dlatikay
    Commented Apr 24, 2018 at 18:30
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    \$\begingroup\$ Yes, I was quite surprised that they asked me. For the cost, I was not expecting that service. \$\endgroup\$
    – Oggie
    Commented Apr 24, 2018 at 19:54
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    \$\begingroup\$ PCBWay just got me as a customer. Thanks for letting us know. \$\endgroup\$
    – dotancohen
    Commented Apr 25, 2018 at 19:04

2 Answers 2

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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.

Chamfered edge connector.

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

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  • \$\begingroup\$ that makes complete sense now. I never even thought about the beveled edges. Thanks! \$\endgroup\$
    – Oggie
    Commented Apr 24, 2018 at 13:13
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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.

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    \$\begingroup\$ 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. \$\endgroup\$
    – Sam
    Commented Apr 24, 2018 at 20:57
  • \$\begingroup\$ @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. \$\endgroup\$
    – pipe
    Commented Apr 25, 2018 at 5:22
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    \$\begingroup\$ @pipe if you look at mechanical standards then youll se that they use chamfer for other than 45 degree angles also. \$\endgroup\$
    – joojaa
    Commented Apr 25, 2018 at 5:47
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    \$\begingroup\$ 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 \$\endgroup\$
    – Mazura
    Commented Apr 25, 2018 at 23:14
  • \$\begingroup\$ Bevel vs Chamfer: sansmachining.com/… \$\endgroup\$
    – PStechPaul
    Commented Aug 5, 2022 at 6:49

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