C.C. Specialty makes a heavy-duty 90-degree head for the Foredom style
flexible shaft porting tools that might work if you must have the tool
perpendicular to the weld: http://ccspecialtytool.com/pages/page03.html
I think I would try using an oval-shaped carbide burr on straight
handpiece first.
David


"Richard Ferguson" wrote in message
...
I have a recurring need to reach inside a closed space and grind a weld.
Sometimes I have enough room to get a right angle die grinder in there, if
I distort the shape, but then I have to distort the shape back, which is
kind of a pain. Sometimes there is not enough space to do that, depending
on the size. I use a 2 inch Roloc disk on the die grinder as a kind of
miniature right angle grinder. The headroom requirement for that setup is
4 inches, more than I would like.

I was thinking that I might make a stationary tool, basically offsetting
the Roloc disk a few inches via a drive belt or chain, to reduce the
headroom required to get inside and grind the weld. The Roloc disk mounts
on a 1/4 inch shaft, so perhaps I could put two bearings and a pulley on
that 1/4 inch shaft, and then run a drive belt to the die grinder, which
would have another pulley on it, using a 1/4 inch shaft mounted in the die
grinder. The sketch at the link below should help, I always have trouble
visualizing what people describe in words, a picture is worth a thousand
words, etc.

http://fergusonsculpture.home.att.net/offset_roloc.jpg

The problem with this concept is that die grinders typically turn at
20,000 RPM. Are there any small drive belts or chains that would survive
that kinds of speeds?

Maybe there is another solution that I have not considered.

Richard


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http://www.fergusonsculpture.com
Sculptures in copper and other metals