I am attempting to build a router table extension to my table saw. Due to a
measuring error while trimming the edge of the tabel with a 1/2 x 1" carbide
straight cut, I clipped the side off of a couple of 1/4 " brass threaded
insert screws. The bit more or less milled the brass level with the side.
There was a bit of a metalic hot smell and the bit and brass were quite warm
to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and sharp.
The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is the
bit OK? Should I try touching up the carbide edge on the inside with a
diamond hone?

Wayne in Boulder CO

You can machine brass with good tools, like carbide. Especially if you
can't see any damage, there probably isn't there. Of course, it almost
never hurts to hone your bits.

Steve

"Wayne" wrote in message
...
I am attempting to build a router table extension to my table saw. Due to a
measuring error while trimming the edge of the tabel with a 1/2 x 1"
carbide straight cut, I clipped the side off of a couple of 1/4 " brass
threaded insert screws. The bit more or less milled the brass level with
the side. There was a bit of a metalic hot smell and the bit and brass were
quite warm to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and sharp.
The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is the
bit OK? Should I try touching up the carbide edge on the inside with a
diamond hone?

Wayne in Boulder CO

Wayne (in ) said:

| I am attempting to build a router table extension to my table saw.
| Due to a measuring error while trimming the edge of the tabel with
| a 1/2 x 1" carbide straight cut, I clipped the side off of a couple
| of 1/4 " brass threaded insert screws. The bit more or less milled
| the brass level with the side. There was a bit of a metalic hot
| smell and the bit and brass were quite warm to the touch.
|
| On inspection I can see nothing wrong with the router bit. There is
| no discoloration from burning, no chips, and the edge feels smooth
| and sharp. The project does not even seem to be ruined.
|
| I know brass is softer than carbide, but its sure harder than wood.
| Is the bit OK? Should I try touching up the carbide edge on the
| inside with a diamond hone?

Probably a good idea to check the bit with a magnifying lens. A touch
up with an extra fine hone probably wouldn't hurt.

Next time slow the router and use coolant. Don't forget safety
glasses. :-)

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/solar.html

About the only thing I'd look for is any chips in the carbide. The
carbide is WAY harder than the fairly soft brass. I don't think you'll
have a problem.

John

I am attempting to build a router table extension to my table saw. Due to a
measuring error while trimming the edge of the tabel with a 1/2 x 1"
carbide straight cut, I clipped the side off of a couple of 1/4 " brass
threaded insert screws. The bit more or less milled the brass level with
the side. There was a bit of a metalic hot smell and the bit and brass were
quite warm to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and sharp.
The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is the
bit OK? Should I try touching up the carbide edge on the inside with a
diamond hone?

I did the same sort of thing building my router table. I was routing for
the fence T-slot and ran into a steel hinge screw. I have no concern about
the bit since it's clear that it "cut" the screw, rather than mashed it.
The same thing happened once or twice on the table saw when I hit a nail.
The nail was just as long as it was when I started, but only half as wide.
In both cases sparks flew, but in neither case was there any difference to
the cutting power of the bit or blade. Carbide is tough! YMMV.

- Owen -

"Wayne" wrote in
:

I am attempting to build a router table extension to my table saw. Due
to a measuring error while trimming the edge of the tabel with a 1/2 x
1" carbide straight cut, I clipped the side off of a couple of 1/4 "
brass threaded insert screws. The bit more or less milled the brass
level with the side. There was a bit of a metalic hot smell and the
bit and brass were quite warm to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and
sharp. The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is
the bit OK? Should I try touching up the carbide edge on the inside
with a diamond hone?

Wayne in Boulder CO



So how much would it cost to replace this bit, and forget worrying about
it?

Patriarch

Wayne wrote:

I am attempting to build a router table extension to my table saw. Due to a
measuring error while trimming the edge of the tabel with a 1/2 x 1" carbide
straight cut, I clipped the side off of a couple of 1/4 " brass threaded
insert screws. The bit more or less milled the brass level with the side.
There was a bit of a metalic hot smell and the bit and brass were quite warm
to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and sharp.
The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is the
bit OK? Should I try touching up the carbide edge on the inside with a
diamond hone?

Wayne in Boulder CO


Not to worry, Wayne. Your bit is fine judging from the soft metal you
said it encountered and your visual inspection bears that out.

Dave

Patriarch wrote:

"Wayne" wrote in
:


I am attempting to build a router table extension to my table saw. Due
to a measuring error while trimming the edge of the tabel with a 1/2 x
1" carbide straight cut, I clipped the side off of a couple of 1/4 "
brass threaded insert screws. The bit more or less milled the brass
level with the side. There was a bit of a metalic hot smell and the
bit and brass were quite warm to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and
sharp. The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is
the bit OK? Should I try touching up the carbide edge on the inside
with a diamond hone?

Wayne in Boulder CO




So how much would it cost to replace this bit, and forget worrying about
it?

Patriarch
You and I both know his bit is fine so why put doubts in his mind? If
he had any remaining doubts all he needs to do is USE the bit and see
that it cuts properly and requires no more effort to cut with than it
did before the non-event of milling some brass.

Dave

"Owen Lawrence" wrote in message
In both cases sparks flew, but in neither case was there any difference to
the cutting power of the bit or blade. Carbide is tough! YMMV.

It's hard yes and maintains its sharpness, but it is prone to shattering on
sudden impact.

"Upscale" wrote in message
...
"Owen Lawrence" wrote in message
In both cases sparks flew, but in neither case was there any difference
to
the cutting power of the bit or blade. Carbide is tough! YMMV.

It's hard yes and maintains its sharpness, but it is prone to shattering
on
sudden impact.

Oh, man! Now you've got me wondering exactly what "sudden impact" could
possibly mean. At 20k RPM I would think almost everything happens suddenly.
Let's do some arithmetic: We're talking 333 RPS. Suppose I'm moving at
one inch/sec, with two blades on the bit, that's about one and a half thou
per nibble. I don't know how fast the thing really turns when it's
cutting, so let's say it goes 10k (a low estimate judging from the change in
musical pitch); that's still only 3 thou at a time.

But point well taken. I certainly wasn't happy about hitting metal with my
router bits, and except for screw ups (no pun intended) I avoid it.
Nevertheless, I don't worry so much about it when it happens. I'm glad I've
never had a carbide anything shatter.

- Owen -

"Owen Lawrence" wrote in message

Oh, man! Now you've got me wondering exactly what "sudden impact" could
possibly mean. At 20k RPM I would think almost everything happens
suddenly.

The carbide on router bits can break when they're accidentally dropped on
the floor. That's the type of sudden impact that I had in mind. Carbide is
extremely hard in one respect, but it has some weaknesses in other respects.

Thanks to everyone for the replies. The valium goes back on the shelf! :-)

Back to work on the table. I will post a picture when its done.

Wayne

"David" wrote in message
...
Wayne wrote:

I am attempting to build a router table extension to my table saw. Due to
a measuring error while trimming the edge of the tabel with a 1/2 x 1"
carbide straight cut, I clipped the side off of a couple of 1/4 " brass
threaded insert screws. The bit more or less milled the brass level with
the side. There was a bit of a metalic hot smell and the bit and brass
were quite warm to the touch.

On inspection I can see nothing wrong with the router bit. There is no
discoloration from burning, no chips, and the edge feels smooth and
sharp. The project does not even seem to be ruined.

I know brass is softer than carbide, but its sure harder than wood. Is
the bit OK? Should I try touching up the carbide edge on the inside with
a diamond hone?

Wayne in Boulder CO
Not to worry, Wayne. Your bit is fine judging from the soft metal you
said it encountered and your visual inspection bears that out.

Dave

Owen Lawrence wrote:

"Upscale" wrote in message
...

"Owen Lawrence" wrote in message

In both cases sparks flew, but in neither case was there any difference
to
the cutting power of the bit or blade. Carbide is tough! YMMV.

It's hard yes and maintains its sharpness, but it is prone to shattering
on
sudden impact.


Oh, man! Now you've got me wondering exactly what "sudden impact" could
possibly mean. At 20k RPM I would think almost everything happens suddenly.
Let's do some arithmetic: We're talking 333 RPS. Suppose I'm moving at
one inch/sec, with two blades on the bit, that's about one and a half thou
per nibble. I don't know how fast the thing really turns when it's
cutting, so let's say it goes 10k (a low estimate judging from the change in
musical pitch); that's still only 3 thou at a time.

But point well taken. I certainly wasn't happy about hitting metal with my
router bits, and except for screw ups (no pun intended) I avoid it.
Nevertheless, I don't worry so much about it when it happens. I'm glad I've
never had a carbide anything shatter.

- Owen -


When you want a REAL thrill, hit a steel plate with a 10" carbide tipped
blade in a TS! I never did find the 24 carbide blade tips, but I sure
heard them hitting the inside of the saw, the pavement, etc! Luckily
none decided to head my way.

Dave

David wrote in
:

snip
So how much would it cost to replace this bit, and forget worrying
about it?

Patriarch
You and I both know his bit is fine so why put doubts in his mind? If
he had any remaining doubts all he needs to do is USE the bit and see
that it cuts properly and requires no more effort to cut with than it
did before the non-event of milling some brass.

Dave


His bit MAY be fine, or maybe not. I can't tell from here. The question
was more one of economics: How much money is it worth to put the question
to rest? Is it a $15 blue wonder from Rockler, or an expensive spiral
cutter from a leading industrial supplier?

He had the doubts, made a post asking a question, without any prompting
from me.

Patriarch,
with reasonable certainty regarding a few things, none of which involve
spinning metal at 20k+ rpm...

David (in ) said:

| When you want a REAL thrill, hit a steel plate with a 10" carbide
| tipped blade in a TS! I never did find the 24 carbide blade tips,
| but I sure heard them hitting the inside of the saw, the pavement,
| etc! Luckily none decided to head my way.

In the aircraft factory next door to my shop they use a miter saw for
cutting aluminum. One of the new guys tried chopping some chrome moly
steel tubing with it and stripped off all 80 teeth. I got a look at
the remains of the blade and a handful of the teeth; and saw that all
of the breaks were in the steel disk - the carbide teeth (and the
carbide-to-steel bonds) were undamaged. The teeth were still sharp and
none that I saw were chipped.

Solid carbide router bits bear a remarkable resemblence to the carbide
end mills commonly used to machine steel, brass, aluminum, etc (the
most common configuration is a spiral up-cut) and I regularly buy end
mills for use in my CNC router because they're often less expensive
and are available in more sizes than router bits.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/solar.html

Yes. The brass is shot. Send the router bit to me.

;-)