Eagle - How to create wire without solder mask ?

Community PCB Design
1

I need to create a double layer pcb where some wire on bottom layer should be without solder mask to add more tin to increase the thickness.

See my actual pcb and the bad work to remove solder mask.

http://www.audiodesignguide.com/Ibridone/pcb2a.gif

http://www.audiodesignguide.com/Ibridone/Ib2014_ph0.jpg

http://www.audiodesignguide.com/Ibridone/Ib2014_ph1.jpg

Pads or Vias can solve my problem or both these will create wires on both layer ?

2

I’m not sure if there is a direct way to do it with the trace properties but what you can do is draw an identical wire on top of the trace you want exposed but change its layer to “tstop” or “bstop” (top/bottom). The STOP layers are used to define areas where the solder mask does not exist. It’s typically used in a polygon to unmask a large area but you can use it with individual wires as well.

-Bill

3

Is this work ok ?

4

The tStop and bStop layers look ok. There are a few things I would change though.

  1. All your traces have 90° angles. For better flow and to prevent acid traps, all angles should be at 45°.

  2. There are no values on your schematic.

  3. You don’t use any positive or negative supply symbols on the schematic.

  4. You have vias inside pads (Attached image)

  5. Traces are too close to the edge.

  6. I would advise you too run a DRC check on the board to highlight all the issues. This will take some time as there are numerous overlap errors due to the method you used to lay them out. You will need to go though all of them to make sure one of them isn’t a real issue.

  7. I don’t know if you are going to lay down the FETs/transistors as the board as them, but you should take into consideration of how they will dissipate heat.

  8. You have unrouted segments.

5

sorry but “You have unrouted segments.” where ?

The first version of this pcb run good and the sound is perferct:

http://www.audiodesignguide.com/Ibridone/index4.html

My problem with the first version of this pcb was to add tin on the high current wires to increase the thickness without before scratching the pcb to remove the solder

http://www.audiodesignguide.com/Ibridone/Ib2014_ph1.jpg

6

Attached is an image where the yellow lines are unrouted segments that are connected via the schematic. Click to enlarge image.

If the board worked before, then by all means, go for it.

7

codlink, thank you very much!

Here the new pcbs created with bStop e tStop

http://www.audiodesignguide.com/Ibridone/index5.html