Hockey pucks have a semi sealed surface on the top and bottom. This must be a result of the manufacturing process. The original set of pucks I did, I had sanded that surfaces (which allowed the R&B to settle into the rough surface.
On the next set I am using the suggested mineral spirits, I now lightly coat the pucks before adding the R&B and wipe it the extra with a paper towel. This removes most of the R&B and doesn’t disrupt the product in deeper groove too much.
After you let the R&B and mineral spirits dry, I can then add the second coat R&B, float some mineral spirits to wipe excess. I will have to sand a little to get the black contract to show through.
The urethane brings back the contrast, but the less R&B on the top surfaces makes it much easier.