3 ms·

> Also note that I only used the small trace size to get to the pads, where it's actually necessary: as any trace that is close to the limits of the board house

> Also note that I only used the small trace size to get to the pads, where it's actually necessary: as any trace that is close to the limits of the board houses capabilities has a chance of not being manufactured correctly, I tried using as little trace length that is minimum-width as possible. I wish we could stop repeating this fallacy. It simply isn’t true. You can specify 100% e-testing if you are that concerned. I’ve had thousands of prototypes PCBs made, and only two failures I can remember, both were from under etching. Never had a NC on a trace running at specified capability.

Sprite_tm 5y ago
You're probably right if you do professional runs. This is the few-bucks mass-production who-cares-its-cheap-as-borscht-anyway process we're talking about; it usually comes with 50% e-testing and I actually have a panelized PCB with traces very close to the minimum come back with a few of the PCBs crossed out. The question then becomes: what about the traces that just made it? Can I run any current through it, will they deteriorate over time? Hence my choice to (advise to) beef up the traces a bit.
- fps-hero 5y ago
  If your getting X’s, why bother? Every PCB place I’ve dealt with tells you test rate and success rate (nominal 95% not factoring in specifics of the PCB). For a prototype run, you are effective guaranteed 4.95x good PCB out of 5 Minimum order. 50% e testing means you still got two out of five.
  - TomVDB 5y ago
    Your “every place” doesn’t fall in the same bin as JLCPCB or PCBWay and similar outfits. I’ve done tons of PCB prototypes at JLCPCB and all you’ll ever receive is blue box, a plastic bag with the PCBs and sometimes a keychain. There’s never a test report. That’s why it $2 for 5 PCB, shipped to you within 48 hours after placing the order.

3 ms·

> Also note that I only used the small trace size to get to the pads, where it's actually necessary: as any trace that is close to the limits of the board house

by fps-hero 5y ago

Sprite_tm 5y ago
You're probably right if you do professional runs. This is the few-bucks mass-production who-cares-its-cheap-as-borscht-anyway process we're talking about; it usually comes with 50% e-testing and I actually have a panelized PCB with traces very close to the minimum come back with a few of the PCBs crossed out. The question then becomes: what about the traces that just made it? Can I run any current through it, will they deteriorate over time? Hence my choice to (advise to) beef up the traces a bit.
- fps-hero 5y ago
  If your getting X’s, why bother? Every PCB place I’ve dealt with tells you test rate and success rate (nominal 95% not factoring in specifics of the PCB). For a prototype run, you are effective guaranteed 4.95x good PCB out of 5 Minimum order. 50% e testing means you still got two out of five.
  - TomVDB 5y ago
    Your “every place” doesn’t fall in the same bin as JLCPCB or PCBWay and similar outfits. I’ve done tons of PCB prototypes at JLCPCB and all you’ll ever receive is blue box, a plastic bag with the PCBs and sometimes a keychain. There’s never a test report. That’s why it $2 for 5 PCB, shipped to you within 48 hours after placing the order.