On Nov 19, 4:47 pm, David Billington
wrote:
wrote:
On Nov 19, 4:21 pm, David Billington
wrote:

wrote:

I have an old cast iron table from a table saw. It has a small
rectangular hole in the center of the table that I want to enlarge for
a router. I thought of a metal blade and a jigsaw yet, that sounds
like it might not realistically work.

Looking for any suggestions..

Thank you,
Keith

A square file?. CI files really easily unless the edge is chilled, in
that case you might need to start with a TC grit file. This should not
take long unless the hole needs to be greatly enlarged.

Thanks,

I have to double the opening essentially making it fit a router
template. I'm not familiar with a TC grit file and I am assuming
this is a diamond hand file? Seems like that might take a while by
hand.

Keith

TC grit file, a file with tungsten carbide grit sort of brazed to the
surface. In the UK, readily available from good DIY stores and
elsewhere, often used on tiles and the other ceramics, glass etc. I have
not seen them in square but have never looked, I do have a round and
half round though. That should only be required if the edge of the CI is
chilled in which case a normal file will just skate over the surface,
once you have removed the chilled surface a normal file should make
quick work of it, saying that you haven't given dimensions. If you
intend to enlarge the hole from 1/2" x 1/2" to 2" x 2" then that would
take a bit of work and a jig saw could help remove the bulk of the
material. Same applies, you can get TC coated jigsaw blades for cutting
ceramic materials, also work on stainless fairly well if nothing better
is to hand.- Hide quoted text -

- Show quoted text -

Thanks. I should have realized Carbide. I have to actually remove
about 8 inches of material going from a 8 in by 4 in wide opening to
an 12 in by 12 in opening. I'lll give it a try thanks.

Keith