PrecisionmachinisT wrote:
"rangerssuck" wrote in message
...
I need to make (or have made) a custom router bit. The groove I need
to make is a truncated V 15/16" wide at the top, 3/8" wide at the
bottom and 1/4" deep. The dimensions aren't super critical, but
closer is better.

I do NOT have a real tool grinder, and HF seems to have discontinued
theirs. I also don't (as will become apparent) have more than a very
little bit of experience grinding tool bits. I DO have 1x30 and 4x36
belt sanders, a set of 5C collets and a square collet block.

I'm thinking that I could lay out the shape on a blank, hold it in
the collet block, set the fence on the sander to 41 1/2° (to form the
V angle), tilt its table to 20° or so (to form the cutting edge and
then grind to the line. Then grind the flat end and its cutting
edges.

Question 1:
Does the above sound reasonable?

I have found a source for HS blanks http://goo.gl/13G1cD but a)
they're not at all cheap and b) they have a half-inch shank and I
have a 1/4" router. I'm not opposed to a new router, but only if I
really need it.

Question 2:
Is there any reason I couldn't start out with a 15/16" spade bit as
my blank? Even the most expensive spade bit is going to be less
expensive than that router bit blank. Is there something about a
spade bit that would make it totally unsuitable for this?

Question 3:
should I just job this out? If so, is there anyone here who would
want to do it? How much should I expect to pay?

Thanks for the input.

===

Probably I would sacrifice an old center drill; spade bits typically
only have a 1/4 diameter shank and so they'll bend very easily if
subjected to much side loading.

Offhand grinding of this sort of tooling is made quite a bit easier
if you use a single flute design.

Won't a single flute cutter run into balance problems at 20,000 plus RPM's ?

--
Snag