grinding pads is a money maker...
Fred,
Here is "pad grinding 101":
The best way to do it is on a radial arm saw with a 10" sanding disk. The disk rotates fast & will really take off the rubber quickly. A relatively coarse grit (120 at the finest) will give good results.
You can build a fixture to hold the butt stock & sand the butt flat & at the correct angle. With no effort, the edges of the wood will be sharp with no chips.
Then screw the pad to the stock. Wrap the wooden butt stock with a thickness of black electrician's tape and then put a layer of masking tape (regular or blue painter's tape) over it.
Carefully hold the stock so the surface is parallel to the sanding disk & sand carefully down to the blue tape all around. If you miss & nick the masking tape, the mistake will stand out but it won't go through to the wood.
When you're down as far as you're comfortable going with the sanding disk, then take off the masking tape and go carefully with a file down to the electrician's tape. After that it's sand paper wrapped on the file, or take the pad off & work it against sand paper on a flat surface, down to the final fit.
Anyway, that's how we do it. Putting on ebony fore end tips is much the same. After gluing on the ebony piece, it can be rounded to the shape of the fore end and the end rounded nicely with the sanding disk.
God bless those trap shooters. The pay $10K for a trap gun & then want you to change it! Putting on a new pad is the usual first step. And then next year, they do it all over again!
Regards, Ron