I made a workbench from some gluelams I got for free. It is quite
substantial, being about 5 inches thick; very solid. I drilled some
bench dog holes in it, and then I bought a holdfast.

Unfortunately, even though the holdfast was described as 3/4" diameter,
it's really a bit larger, and I need to enlarge the dog holes by about
1/8". I saw one technique where you grind the shoulders of a spade bit
at 60 degrees and proceed carefully down the holes to enlarge them.
Does anyone have better ideas?

Also, I initially drilled too many holes. Any thoughts on plugging
them? I might just glue in some dowels, but someone might have a more
elegant idea.

Thanks,

scritch