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.

"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.

====
You didn't mention the material it must cut. Soft wood doesn't need
HSS tools.

If the groove is straight with open ends there are other ways to cut
it.
-jsw

On 7/21/2014 4:13 PM, rangerssuck wrote:
...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. ...

How much of this groove do you need to make? One time? Or production?

"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.

I've made a few different specialty cutters for one off jobs on my CNC mill
by cutting a piece out of plane old 1018 sharpening it, case hardening, and
the resharpening. I've also made a few cutters that didn't have to hold up
at all by scribing a piece, and free hand grinding back and forth between
the bench grinder and the belt sander.

So what are you cutting? How much of it are you cutting? Will you need to
rinse and repeat? Sine you specifically said router, then I am guessing
wood, but I do use a router for cutting aluminum and brass sometimes too.

Bob Engelhardt wrote:
On 7/21/2014 4:13 PM, rangerssuck wrote:
...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. ...

How much of this groove do you need to make? One time? Or
production?

Can it be done by using a 45° vee bit and a standard plunge bit ? You might
be able to regrind the angle of a 45° chanfer bit and cut the pilot off
and use it to angle the sides of a 3/8" groove .

--
Snag

Please make 2. I need one also.
I need mine for cutting the "belt" groove in perimeter of a 30" diameter spinning wheel's driving wheel. I have been looking for exactly that profile for a long time.

Pete Stanaitis
---------------

"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.

"Terry Coombs"
wrote in message
Bob Engelhardt wrote:
On 7/21/2014 4:13 PM, rangerssuck wrote:
...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.
...

How much of this groove do you need to make?
One time? Or
production?

Can it be done by using a 45° vee bit and a
standard plunge bit ? You might be able to
regrind the angle of a 45° champher bit and cut
the pilot off and use it to angle the sides of
a 3/8" groove .

--
Snag


Snag, are you saying do it in two passes? I like
that
idea as it will solve the chip interference action
when
done in one pass.

On Monday, July 21, 2014 8:13:23 PM UTC, rangerssuck wrote:
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.



Thanks for the input.

Would you settle for a standard router bit that makes the groove?

I looked at the router bits that I have and found that I think is for trimming formica. It is too wide at the top as it is an inch wide. But you can reduce that to 15/16ths by setting the depth so the groove it cuts is 15/16 inch wide.

The bottom has a ball bearing which you need to remove. I eyeballed it at about 3/8 inch. Can go back down to the basement, remove the bearing and see what the actual width is at the bottom. The cutting edges may work well at the bottom. But you can use a 3/8 straight router bit first and then use the 45 degree bit. I think that will work to get what you want.

The router bits I have are from Harbor Freight, but the web site does not give good dimensions.

Could not find the router bit on ebay.

Dan

On Mon, 21 Jul 2014 13:13:23 -0700 (PDT), rangerssuck
wrote:

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.
Do you have a milling machine or a milling attachment for your lathe?
If so, then get some drill rod, turn the profile you want, transfer
the part to your collet block, then mill the teeth in the part. Heat
treat with a torch and then stone the teeth after the cutter has been
hardened and tempered. If you can get by with just one cutting edge
then mount your cutter blank in the lathe eccentrically. This can be
done just by using a shim between one jaw and the blank in a three jaw
chuck. Or use a 4 jaw chuck. Then mill the blank to get the one
cutting edge. Then when the tool gets dull you only need to sharpen
the top of the one tooth. The eccentricity of the tool will provide
constant relief. You cound even make a one tooth cutter with the lathe
and a bench grinder. Just use the grinder instead of the mill. I have
made many custom cutters this way. Using the mill though, not the
bench grinder. I have sharpened my custom cutters on the bench grinder
though. It is pretty easy to make your own cutter this way and you can
even cut steel if you harden the cutter properly. Just about two
months ago I whipped out a special single flute cutter just the way I
described above because the special one I ordered hadn't arrived yet
and I needed to get the parts out the door.
Eric

Phil Kangas wrote:
"Terry Coombs"
wrote in message
Bob Engelhardt wrote:
On 7/21/2014 4:13 PM, rangerssuck wrote:
...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.
...

How much of this groove do you need to make?
One time? Or
production?

Can it be done by using a 45° vee bit and a
standard plunge bit ? You might be able to
regrind the angle of a 45° champher bit and cut
the pilot off and use it to angle the sides of
a 3/8" groove .

--
Snag


Snag, are you saying do it in two passes? I like
that
idea as it will solve the chip interference action
when
done in one pass.

I spent 20 years in cabinet shops , often with a very limited tooling
budget . The boss liked it when I could make two $12 tooling items do the
job of a single $165 tool ...
To answer your question more directly , yes , 2 tools and a total of 3
passes - groove , near side then far side on the return pass . This approach
will need fences/guides and a very accurate setup .
--
Snag

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

On Mon, 21 Jul 2014 21:17:59 -0500, "Terry Coombs"
wrote:

Phil Kangas wrote:
"Terry Coombs"
wrote in message
Bob Engelhardt wrote:
On 7/21/2014 4:13 PM, rangerssuck wrote:
...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.
...

How much of this groove do you need to make?
One time? Or
production?

Can it be done by using a 45° vee bit and a
standard plunge bit ? You might be able to
regrind the angle of a 45° champher bit and cut
the pilot off and use it to angle the sides of
a 3/8" groove .

--
Snag


Snag, are you saying do it in two passes? I like
that
idea as it will solve the chip interference action
when
done in one pass.

I spent 20 years in cabinet shops , often with a very limited tooling
budget . The boss liked it when I could make two $12 tooling items do the
job of a single $165 tool ...
To answer your question more directly , yes , 2 tools and a total of 3
passes - groove , near side then far side on the return pass . This approach
will need fences/guides and a very accurate setup .

+1

--
"When the people fear their government, there is tyranny; when the
government fears the people, there is liberty."
Attributed to Thomas Jefferson, but Massah Ed, he doan tink it so.

On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:
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.

Thanks for the input so far, and here are some answers to the questions that were raised:
1) The project is modifying the double-hung windows in my house to work with replacement jamb-liners. These are spring-loaded and are the mechanism from jeld-wen windows, purchased from an outfit in Milwaukee. They used to sell a router bit for the purpose, but they say they can't get the blanks anymore - what they were actually doing is modifying an HSS v-groove cutter that has been discontinued by Sears. I had purchased a bit from them and it's done OK, but then I hit a nail and even though I've resharpened, it's not going to put up with that too many times and I have 25 more windows (50 more grooves) to do. The material I'm cutting is chestnut oak.

I have to do these windows one or two at a time, as the whole job is kind of big and I don't want to disassemble all 25 windows at once.

I have a router table (shop made) set up to do this with the appropriate fences and feather boards, and I'd much rather not have to switch bits for each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with the bearing removed would probably do a great job, but it's either a bit change or a second machine. Also, having standard-size cutters (and carbide, too) would be a major plus.

As for the spade bit being only a 1/4" shank, the router (and bit) that I have now is 1/4" shank, and that's not a problem.

What I would REALLY like is a shaper table to do this, but that's not in the cards now, and would still involve either two passes or a custom cutter.

If I could come up with a way to do a quick-change of the bits (straight & V) that would get them to the same height (perhaps a small collar under one or the other if they're close to begin with the bit-switching wouldn't be so bad. If I have to adjust the height each time, it would be a bitch - my router table doesn't have a lift mechanism.

But back to the original question - is there anything inherently bad about using a modified spade bit in a router? Would it be likely to fly apart at speed if it was slightly off balance? [I've done some design work on controls for 90K RPM motors and seen some spectacular failures]

"rangerssuck" wrote in message
...
On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:
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.


Since the grooves are straight with open ends you might consider
making a molding plane, thus trading off an easier-to-make steel blade
for a little woodworking. Dull circular saw blades can be annealed,
cut up and rehardened.
http://www.hyperkitten.com/tools/art...ane_Basics.php

-jsw

On Tuesday, July 22, 2014 11:15:12 AM UTC-4, Jim Wilkins wrote:
"rangerssuck" wrote in message

...

On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:

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.





Since the grooves are straight with open ends you might consider

making a molding plane, thus trading off an easier-to-make steel blade

for a little woodworking. Dull circular saw blades can be annealed,

cut up and rehardened.

http://www.hyperkitten.com/tools/art...ane_Basics.php



-jsw

I've seen those - The Woodright's shop is one of my all time favorites - but I have about 300 feet of this to do, and I'd like to get it done in my lifetime.

On Mon, 21 Jul 2014 21:19:55 -0500, "Terry Coombs"
wrote:

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 ?
It might at that. I have used single flute cutters at high speeds but
not 20,000 RPM. It would not be hard though to grind away material on
the other side of the cutter. This would limit how many times the
cutter could be resharpened but not by much.
Eric

"rangerssuck" wrote in message
...
On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:
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.

Thanks for the input so far, and here are some answers to the questions that
were raised:
1) The project is modifying the double-hung windows in my house to work with
replacement jamb-liners. These are spring-loaded and are the mechanism from
jeld-wen windows, purchased from an outfit in Milwaukee. They used to sell a
router bit for the purpose, but they say they can't get the blanks anymore -
what they were actually doing is modifying an HSS v-groove cutter that has
been discontinued by Sears. I had purchased a bit from them and it's done
OK, but then I hit a nail and even though I've resharpened, it's not going
to put up with that too many times and I have 25 more windows (50 more
grooves) to do. The material I'm cutting is chestnut oak.

I have to do these windows one or two at a time, as the whole job is kind of
big and I don't want to disassemble all 25 windows at once.

I have a router table (shop made) set up to do this with the appropriate
fences and feather boards, and I'd much rather not have to switch bits for
each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with
the bearing removed would probably do a great job, but it's either a bit
change or a second machine. Also, having standard-size cutters (and carbide,
too) would be a major plus.

As for the spade bit being only a 1/4" shank, the router (and bit) that I
have now is 1/4" shank, and that's not a problem.

What I would REALLY like is a shaper table to do this, but that's not in the
cards now, and would still involve either two passes or a custom cutter.

If I could come up with a way to do a quick-change of the bits (straight &
V) that would get them to the same height (perhaps a small collar under one
or the other if they're close to begin with the bit-switching wouldn't be so
bad. If I have to adjust the height each time, it would be a bitch - my
router table doesn't have a lift mechanism.

But back to the original question - is there anything inherently bad about
using a modified spade bit in a router? Would it be likely to fly apart at
speed if it was slightly off balance? [I've done some design work on
controls for 90K RPM motors and seen some spectacular failures]

A paddle bit will twist up as soon as it hits the wood and screw up the job
and probably put your eye out.

I assume you are plowing the sashes to fit the patent balance.

From the dimensions and the descriptions of the modified tool this angle is
close enough to 45deg to be designed that way.

Don't reinvent the wheel.

Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in
two passes.
http://www.mlcswoodworking.com/shops...-Groove_Anchor

The blunted end will leave the bottom fuzzy but it probably won't make any
difference because the sashes probably locate on the bevel before they
bottom out on the flat.

Paul K. Dickman

How about this:

- 1 pass through the router with a 3/8" straight cutter
- 2 passes through the table saw with the blade tilted to your angle
(stock turned end-to-end for 2nd pass)

If grove is not centered on the stock, the 2nd saw pass would require
moving the fence. Or better, having an offset piece clamped to the fence.

No bit changes, or set up changes except for the possible saw fence offset.

Bob

"rangerssuck" wrote in message
...
On Tuesday, July 22, 2014 11:15:12 AM UTC-4, Jim Wilkins wrote:
"rangerssuck" wrote in message


Since the grooves are straight with open ends you might consider

making a molding plane, thus trading off an easier-to-make steel
blade

for a little woodworking. Dull circular saw blades can be annealed,

cut up and rehardened.

http://www.hyperkitten.com/tools/art...ane_Basics.php



-jsw

I've seen those - The Woodright's shop is one of my all time
favorites - but I have about 300 feet of this to do, and I'd like to
get it done in my lifetime.

You only have to plane what you can't remove with a straight router
bit.
-jsw

On 7/22/2014 12:10 PM, Bob Engelhardt wrote:
How about this:

- 1 pass through the router with a 3/8" straight cutter
- 2 passes through the table saw with the blade tilted to your angle
(stock turned end-to-end for 2nd pass)

If grove is not centered on the stock, the 2nd saw pass would require
moving the fence. Or better, having an offset piece clamped to the fence.

No bit changes, or set up changes except for the possible saw fence offset.

Bob


oh, wait ... your angle is more than 45 degrees (90 - 41-1/2 = 48-1/2)
and your table saw blade might not tilt more than 45 (mine doesn't).
You could get around this by lifting the fence side of the stock, but
that's getting kind of ugly.

Still, overall, it's fast, straight forward, cheap, simple, ...

Bob

On Tuesday, July 22, 2014 12:10:02 PM UTC-4, Paul K. Dickman wrote:
"rangerssuck" wrote in message

...

On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:

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.



Thanks for the input so far, and here are some answers to the questions that

were raised:

1) The project is modifying the double-hung windows in my house to work with

replacement jamb-liners. These are spring-loaded and are the mechanism from

jeld-wen windows, purchased from an outfit in Milwaukee. They used to sell a

router bit for the purpose, but they say they can't get the blanks anymore -

what they were actually doing is modifying an HSS v-groove cutter that has

been discontinued by Sears. I had purchased a bit from them and it's done

OK, but then I hit a nail and even though I've resharpened, it's not going

to put up with that too many times and I have 25 more windows (50 more

grooves) to do. The material I'm cutting is chestnut oak.



I have to do these windows one or two at a time, as the whole job is kind of

big and I don't want to disassemble all 25 windows at once.



I have a router table (shop made) set up to do this with the appropriate

fences and feather boards, and I'd much rather not have to switch bits for

each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with

the bearing removed would probably do a great job, but it's either a bit

change or a second machine. Also, having standard-size cutters (and carbide,

too) would be a major plus.



As for the spade bit being only a 1/4" shank, the router (and bit) that I

have now is 1/4" shank, and that's not a problem.



What I would REALLY like is a shaper table to do this, but that's not in the

cards now, and would still involve either two passes or a custom cutter.



If I could come up with a way to do a quick-change of the bits (straight &

V) that would get them to the same height (perhaps a small collar under one

or the other if they're close to begin with the bit-switching wouldn't be so

bad. If I have to adjust the height each time, it would be a bitch - my

router table doesn't have a lift mechanism.



But back to the original question - is there anything inherently bad about

using a modified spade bit in a router? Would it be likely to fly apart at

speed if it was slightly off balance? [I've done some design work on

controls for 90K RPM motors and seen some spectacular failures]



A paddle bit will twist up as soon as it hits the wood and screw up the job

and probably put your eye out.



I assume you are plowing the sashes to fit the patent balance.



From the dimensions and the descriptions of the modified tool this angle is

close enough to 45deg to be designed that way.



Don't reinvent the wheel.



Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in
two passes.

http://www.mlcswoodworking.com/shops...-Groove_Anchor

The blunted end will leave the bottom fuzzy but it probably won't make any
difference because the sashes probably locate on the bevel before they
bottom out on the flat.

Paul K. Dickman

This raises an interesting question (setting aside that the 5/8 is too small and I'd have to go to the 3/4" size) : are the dimensions that I have, supplied by the distributor, correct? They are probably "close enough for government work" but if you're a carpenter with a ruler that only goes to 16ths, they many not be correct, and the angle may well be 45° rather than 41.6°.

I will check the dimensions today.

Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in
two passes.

Why two passes?

On Tuesday, July 22, 2014 12:21:24 PM UTC-4, Bob Engelhardt wrote:
On 7/22/2014 12:10 PM, Bob Engelhardt wrote:

How about this:



- 1 pass through the router with a 3/8" straight cutter

- 2 passes through the table saw with the blade tilted to your angle

(stock turned end-to-end for 2nd pass)



If grove is not centered on the stock, the 2nd saw pass would require

moving the fence. Or better, having an offset piece clamped to the fence.



No bit changes, or set up changes except for the possible saw fence offset.



Bob





oh, wait ... your angle is more than 45 degrees (90 - 41-1/2 = 48-1/2)

and your table saw blade might not tilt more than 45 (mine doesn't).

You could get around this by lifting the fence side of the stock, but

that's getting kind of ugly.



Still, overall, it's fast, straight forward, cheap, simple, ...



Bob

Indeed, the calculated angle is 41.6°. But as I replied to Paul, I'm thinking that I should do some actual measuring rather than going by the sketch from the supplier. I will do so later today.

On 7/22/2014 11:21 AM, rangerssuck wrote:
On Tuesday, July 22, 2014 11:15:12 AM UTC-4, Jim Wilkins wrote:
"rangerssuck" wrote in message

...

On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:

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.





Since the grooves are straight with open ends you might consider

making a molding plane, thus trading off an easier-to-make steel blade

for a little woodworking. Dull circular saw blades can be annealed,

cut up and rehardened.

http://www.hyperkitten.com/tools/art...ane_Basics.php



-jsw

I've seen those - The Woodright's shop is one of my all time favorites - but I have about 300 feet of this to do, and I'd like to get it done in my lifetime.


You are not removing much material. With straight, flat material, a
sharp plane, and a guide, I'd guess about it would take less than two
minutes for an eight foot groove.

How about cutting a central dado, and two passes on a router table over
a v groove bit to form the sides? Or form the sides with a tilted table
saw blade?

Or a molding head for the table saw? Custom molding cutters are easier
to shape than creating a router bit.

"rangerssuck" wrote in message
...
On Tuesday, July 22, 2014 12:10:02 PM UTC-4, Paul K. Dickman wrote:
"rangerssuck" wrote in message

...

On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:

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.



Thanks for the input so far, and here are some answers to the questions
that

were raised:

1) The project is modifying the double-hung windows in my house to work
with

replacement jamb-liners. These are spring-loaded and are the mechanism
from

jeld-wen windows, purchased from an outfit in Milwaukee. They used to sell
a

router bit for the purpose, but they say they can't get the blanks
anymore -

what they were actually doing is modifying an HSS v-groove cutter that has

been discontinued by Sears. I had purchased a bit from them and it's done

OK, but then I hit a nail and even though I've resharpened, it's not going

to put up with that too many times and I have 25 more windows (50 more

grooves) to do. The material I'm cutting is chestnut oak.



I have to do these windows one or two at a time, as the whole job is kind
of

big and I don't want to disassemble all 25 windows at once.



I have a router table (shop made) set up to do this with the appropriate

fences and feather boards, and I'd much rather not have to switch bits for

each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with

the bearing removed would probably do a great job, but it's either a bit

change or a second machine. Also, having standard-size cutters (and
carbide,

too) would be a major plus.



As for the spade bit being only a 1/4" shank, the router (and bit) that I

have now is 1/4" shank, and that's not a problem.



What I would REALLY like is a shaper table to do this, but that's not in
the

cards now, and would still involve either two passes or a custom cutter.



If I could come up with a way to do a quick-change of the bits (straight &

V) that would get them to the same height (perhaps a small collar under
one

or the other if they're close to begin with the bit-switching wouldn't be
so

bad. If I have to adjust the height each time, it would be a bitch - my

router table doesn't have a lift mechanism.



But back to the original question - is there anything inherently bad about

using a modified spade bit in a router? Would it be likely to fly apart at

speed if it was slightly off balance? [I've done some design work on

controls for 90K RPM motors and seen some spectacular failures]



A paddle bit will twist up as soon as it hits the wood and screw up the
job

and probably put your eye out.



I assume you are plowing the sashes to fit the patent balance.



From the dimensions and the descriptions of the modified tool this angle
is

close enough to 45deg to be designed that way.



Don't reinvent the wheel.



Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in
two passes.

http://www.mlcswoodworking.com/shops...-Groove_Anchor

The blunted end will leave the bottom fuzzy but it probably won't make any
difference because the sashes probably locate on the bevel before they
bottom out on the flat.

Paul K. Dickman

This raises an interesting question (setting aside that the 5/8 is too small
and I'd have to go to the 3/4" size) : are the dimensions that I have,
supplied by the distributor, correct? They are probably "close enough for
government work" but if you're a carpenter with a ruler that only goes to
16ths, they many not be correct, and the angle may well be 45° rather than
41.6°.

I will check the dimensions today.

Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in
two passes.

Why two passes?

Because the 5/8 is too small.

Paul K. Dickman

On Tuesday, July 22, 2014 1:13:45 PM UTC-4, Paul K. Dickman wrote:
"rangerssuck" wrote in message

...

On Tuesday, July 22, 2014 12:10:02 PM UTC-4, Paul K. Dickman wrote:

"rangerssuck" wrote in message



...



On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:



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.







Thanks for the input so far, and here are some answers to the questions

that



were raised:



1) The project is modifying the double-hung windows in my house to work

with



replacement jamb-liners. These are spring-loaded and are the mechanism

from



jeld-wen windows, purchased from an outfit in Milwaukee. They used to sell

a



router bit for the purpose, but they say they can't get the blanks

anymore -



what they were actually doing is modifying an HSS v-groove cutter that has



been discontinued by Sears. I had purchased a bit from them and it's done



OK, but then I hit a nail and even though I've resharpened, it's not going



to put up with that too many times and I have 25 more windows (50 more



grooves) to do. The material I'm cutting is chestnut oak.







I have to do these windows one or two at a time, as the whole job is kind

of



big and I don't want to disassemble all 25 windows at once.







I have a router table (shop made) set up to do this with the appropriate



fences and feather boards, and I'd much rather not have to switch bits for



each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with



the bearing removed would probably do a great job, but it's either a bit



change or a second machine. Also, having standard-size cutters (and

carbide,



too) would be a major plus.







As for the spade bit being only a 1/4" shank, the router (and bit) that I



have now is 1/4" shank, and that's not a problem.







What I would REALLY like is a shaper table to do this, but that's not in

the



cards now, and would still involve either two passes or a custom cutter..







If I could come up with a way to do a quick-change of the bits (straight &



V) that would get them to the same height (perhaps a small collar under

one



or the other if they're close to begin with the bit-switching wouldn't be

so



bad. If I have to adjust the height each time, it would be a bitch - my



router table doesn't have a lift mechanism.







But back to the original question - is there anything inherently bad about



using a modified spade bit in a router? Would it be likely to fly apart at



speed if it was slightly off balance? [I've done some design work on



controls for 90K RPM motors and seen some spectacular failures]







A paddle bit will twist up as soon as it hits the wood and screw up the

job



and probably put your eye out.







I assume you are plowing the sashes to fit the patent balance.







From the dimensions and the descriptions of the modified tool this angle

is



close enough to 45deg to be designed that way.







Don't reinvent the wheel.







Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in

two passes.



http://www.mlcswoodworking.com/shops...-Groove_Anchor



The blunted end will leave the bottom fuzzy but it probably won't make any

difference because the sashes probably locate on the bevel before they

bottom out on the flat.



Paul K. Dickman



This raises an interesting question (setting aside that the 5/8 is too small

and I'd have to go to the 3/4" size) : are the dimensions that I have,

supplied by the distributor, correct? They are probably "close enough for

government work" but if you're a carpenter with a ruler that only goes to

16ths, they many not be correct, and the angle may well be 45� rather than

41.6�.



I will check the dimensions today.



Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut in

two passes.



Why two passes?



Because the 5/8 is too small.

more easily dealt with by going up to the 3/4" bit and lowering it in the router table, I think.

BTW, #5419 on http://www.mlcswoodworking.com/shops...-Groove_Anchor is, except for the totally wrong dimensions, exactly what I need. It cuts a v-groove with a flat bottom.

"rangerssuck" wrote in message
...
On Tuesday, July 22, 2014 1:13:45 PM UTC-4, Paul K. Dickman wrote:
"rangerssuck" wrote in message

...

On Tuesday, July 22, 2014 12:10:02 PM UTC-4, Paul K. Dickman wrote:

"rangerssuck" wrote in message



...



On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:



I need to make (or have made) a custom router bit. The groove I need
to


snip

A paddle bit will twist up as soon as it hits the wood and screw up the

job



and probably put your eye out.
I assume you are plowing the sashes to fit the patent balance.


From the dimensions and the descriptions of the modified tool this angle

is close enough to 45deg to be designed that way.


Don't reinvent the wheel.



Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut
in

two passes.



http://www.mlcswoodworking.com/shops...-Groove_Anchor



The blunted end will leave the bottom fuzzy but it probably won't make
any

difference because the sashes probably locate on the bevel before they

bottom out on the flat.



Paul K. Dickman



This raises an interesting question (setting aside that the 5/8 is too
small

and I'd have to go to the 3/4" size) : are the dimensions that I have,

supplied by the distributor, correct? They are probably "close enough for

government work" but if you're a carpenter with a ruler that only goes to

16ths, they many not be correct, and the angle may well be 45? rather
than

41.6?.



I will check the dimensions today.



Buy a 5/8" 45deg. v-grooving bit. Blunt the end to around 3/16 and cut
in

two passes.



Why two passes?



Because the 5/8 is too small.

more easily dealt with by going up to the 3/4" bit and lowering it in the
router table, I think.

BTW, #5419 on
http://www.mlcswoodworking.com/shops...-Groove_Anchor
is, except for the totally wrong dimensions, exactly what I need. It cuts a
v-groove with a flat bottom.

Pardon me for snipping, but it replies were staritng to sprawl.

Your are missing my idea.
By grinding back the point of the vee bit, you create a flat in the center.
The flat won't cut prefectly, but the bevels will do most of the cutting.
If that flat is around 3/16 in dia, it will take two passes to cut it to the
3/8 width.

Since they were making these from stock cutters, I strongly suspect that
angle is 45deg.
These don't come standard in 41.6 deg.
It is not inconceivable that they would fully grind a new angle, but it
would be a pain in the butt to get the relief right. I think it is more
likely that they just ground a couple of flutes on the end to bottom cut the
flat.


Paul K. Dickman

"Terry Coombs" wrote in message ...
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 ?


Probably not enough to be a problem with a 1/2in diameter tool, especially if the router motor is mounted to a table.

However, that's not to say that the gullet on the opposite side could not be gashed away to effect a better balance if desired.....it's just that without proper fixturing, it's a hell of a lot easier to grind a single lip that it is to grind two of them and have both cutting edges end up being reasonably concentric to the rotational centerline.

On Tuesday, July 22, 2014 1:41:01 PM UTC, rangerssuck wrote:


I have a router table (shop made) set up to do this with the appropriate fences and feather boards, and I'd much rather not have to switch bits for each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with the bearing removed would probably do a great job, but it's either a bit change or a second machine. Also, having standard-size cutters (and carbide, too) would be a major plus.



You said the magic words. Second machine. Either a used one off craigslist or one from Harbor Freight . They have a trim rounter for $29.95 and with just a little effort you can find a 25% off coupon. Sometimes on sale for about $20.
Set the second router up with the 3/8 straight and leave it set up until you have done all the windows.

http://www.harborfreight.com/1-4-qua...ter-44914.html

Dan

On Tue, 22 Jul 2014 06:41:01 -0700 (PDT), rangerssuck
wrote:

On Monday, July 21, 2014 4:13:23 PM UTC-4, rangerssuck wrote:
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.

Thanks for the input so far, and here are some answers to the questions that were raised:
1) The project is modifying the double-hung windows in my house to work with replacement jamb-liners. These are spring-loaded and are the mechanism from jeld-wen windows, purchased from an outfit in Milwaukee. They used to sell a router bit for the purpose, but they say they can't get the blanks anymore - what they were actually doing is modifying an HSS v-groove cutter that has been discontinued by Sears. I had purchased a bit from them and it's done OK, but then I hit a nail and even though I've resharpened, it's not going to put up with that too many times and I have 25 more windows (50 more grooves) to do. The material I'm cutting is chestnut oak.

I have to do these windows one or two at a time, as the whole job is kind of big and I don't want to disassemble all 25 windows at once.

I have a router table (shop made) set up to do this with the appropriate fences and feather boards, and I'd much rather not have to switch bits for each cut. I imagine that two passes (3/8 straight) and a 45 v-groove with the bearing removed would probably do a great job, but it's either a bit change or a second machine. Also, having standard-size cutters (and carbide, too) would be a major plus.

As for the spade bit being only a 1/4" shank, the router (and bit) that I have now is 1/4" shank, and that's not a problem.

What I would REALLY like is a shaper table to do this, but that's not in the cards now, and would still involve either two passes or a custom cutter.

If I could come up with a way to do a quick-change of the bits (straight & V) that would get them to the same height (perhaps a small collar under one or the other if they're close to begin with the bit-switching wouldn't be so bad. If I have to adjust the height each time, it would be a bitch - my router table doesn't have a lift mechanism.

But back to the original question - is there anything inherently bad about using a modified spade bit in a router? Would it be likely to fly apart at speed if it was slightly off balance? [I've done some design work on controls for 90K RPM motors and seen some spectacular failures]

I would use a shaper head and knives on a table or radial arm saw.
Regrind the knives to the desired shape.
http://www.sears.com/search=shaper%2...aper%20cutters