Solder Mask broken ring

[froy]

Hi,

I’m trying to create a solder mask for a ring around a plated hole that is broken into 4 places, Another way to view this is a discontinuous solder ring. I don’t see any way of doing this.

Thanks,
frank

[haroldocalvo]

Hi Frank,

Here a 4 step method for that:

1. Create a NPTH (uncheck the plated checkbox)
   

   
   
   
   
   
   

2. Create the copper ring (aka plating) using the circle tool, please select the copper layer and
   check the outline checkbox, also associate the corresponding pin:
   

   
   
   
   
   The circle radius can be calculated using this formula
   Drill hole diameter>dhd
   Plating diameter>pd

Copper circle diameter=(pd+dhd)/4
Outline width=(pd-dhd)/2

In this example I have used pd=1.57mm and dhd=1.02mm
Copper circle diameter=0.6475mm
Outline width=0.275mm

Repeat step 2 for the bottom copper layer.

3. Create the solder-mask using the line tool, select arc, set the same radius and
   outline width as before or change it according to your specs:
   
   
   
   The coordinates for the arc are a bit tricky, in this example I would use an specific
   gap between the arcs and some trigonometry formulas to calculate them:
   
   
   

r=arc radius=0.6475 as was calculated previously
gap=0.2mm

Once a single point is calculated the rest are the same but with the sign and x,y coordinates
switched.

Repeat step #3 for the bottom solder-mask.

4. For the top and bottom solder-paste layer repeat step #3 but assign the solder-paste layer instead.

Hope this answers your question.

[froy]

Thanks Harold

  frank

[haroldocalvo]

You’re welcome, let me know if you have problems calculating the coordinates.

[froy]

Thnx Haroldo,

  It would have taken me a lot of time to figure this out.

  The suggested arcs have 90deg edges.

  But this a is good approximation.

  frank

[mwoodworth33]

Thanks for jumping in @haroldocalvo

[haroldocalvo]

You’re welcome