On Sat, 12 Oct 2013 09:27:38 -0700, scritch
wrote:

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

I made my dog holes with a router and bearing guided router bit. They
ended up perfectly square to the table. You could enlarge an existing
hole by drilling an enlarged hole in a scrap piece and clamp that
scrap over the existing hole, then enlarge with the router. Once the
hole is started, you can go deeper in stages if the router bit is not
long enough.