Best method to have a class of traces that are unmasked to allow solder to add to the current capacity

[chris_cummingsDT]

Hello! I am wondering if there is a way to set up a class of nets (traces) that would be exposed to the soldering process to add current carrying capacity. I see this done in power supplies often. We have some traces that need to be in excess of 200 mils (1oz - 8A - 10 degree rise - outside layer - 208 mils) but do not have the space for that. 

[jorge_garcia]

Hi @chris_cummingsDT,

I hope you're doing well. It's possible to do it, but you have to expose the traces manually. What I mean is that there is no automatic setting for exposing certain traces and not others.

If you have to do this to a lot of traces you could use the copy-wire-to-soldermask.ulp that comes with Fusion 360 Electronics to copy all of the traces to the stop mask and then delete stop masks for traces you want to stay covered.

Let me know if there's anything else I can do for you.

Best Regards,

[chris_cummingsDT]

Wow! I could never have come up with that solution! Thanks, Jorge!

The horridly marked-up sketch includes the traces we are concerned about. Some due to unknowns like loads we have not yet thought of. Since they are major minority of all traces, I hate to bring all the traces to the Stop Mask. So doing this manually, we have to copy the traces, not move them, since we still want copper. Can an Entire Net be copied?

[jorge_garcia · Accepted solution]

Hi @chris_cummingsDT,

I was checking the documentation for that ULP and it allows you to specify the nets you want copied so you would just type:

RUN copy-wire-to-soldermask NET1 NET2 NET3 NET...

Then press enter and it will only copy those nets to the solder mask layer to expose them.

Let me know if there's anything else I can do for you.

Best Regards,

[chris_cummingsDT]

Thanks again, Jorge!

Can you please have someone check Report ID 720390859?

[jorge_garcia]

Hi @chris_cummingsDT,

I hope you're doing well. I passed this along to the team for review.

Let me know if there's anything else I can do for you.

Best Regards,

[chris_cummingsDT]

As always, you are at the top of the food chain, Jorge, and Autodesk has a LOT of great people.

Marty's problem may have been that it did not like the mis-spelled command. The copy-wire-to-solder-mask command has that pesky dash between solder and mask.

I had originally thought the command was not working for me either, but then I found this:

https://forums.autodesk.com/t5/fusion-360-electronics/solder-mask-in-3d-pcb-ignores-tstop-and-bstop/...

I am not sure how to turn Canvas on in my 3D view, that was not showing the exposed  trace, but the Manufacturing Preview showed it just just fine, and this is exactly what we need: