On Fri, 25 Mar 2005 10:10:10 -0700, Tim Killian



Greetings Tim,
The inserts I've seen were all glued in. Having an insert expanded
into the granite might be a bad thing. Really, a surface plate needs
to be stress free to maintain it's really flat surface. The Keenserts
that were mentioned are made to be used with regular taps. They are
solid with threads on the outside as well as the inside. They are
available in many different alloys. If epoxy doesn't thrill you there
is another solution. It's an adhesive called ROCKSETT. Flexbar sells
it. It would work very well for your situation.
http://flexbar.com/Merchant2/merchan...uct_Code=15014
The above link will get you to a place that sells it. I believe
Flexbar also sells the threaded inserts.
Cheers,
Eric

wrote:

Thanks to all for the suggestions. The surface plate is 4" thick, and I
need to put in 12 holes, so going all the way through with a bit less
than 1/2" diameter is not too appealing ;-)

We use helicoils all the time and I'm familiar with that type of insert.
I was hoping someone made a high quality expanding insert with hardened
internal threads specifically for use in stone materials. The galvanized
stuff they sell at HD is really intended for one use only.

Maybe the best solution is a helicoil insert epoxied into the plate.

Tom Gardner wrote:

Do the holes have to be blind? Drill all the way through and put flanged
inserts in if you can.
(top posted the right way)

"Tim Killian" wrote in message
...

I need to add some 1/4-20 threaded, blind holes to a 4" thick granite
surface plate, and I found a diamond core drill that will make the holes.
What is the best type of thread insert to use for this application?