I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?

John Martin

On 17 Oct 2005 16:46:00 -0700, "John Martin"
wrote:

I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?


In this situation the best method is to weld a bead on the inside of
the race. I prefer 7018 stick for this but any welding process will
work. The main key is to get the race red hot fast and let it cool.
Once cool it will fall out of the bore. Larger bearings will require
more than one pass.


Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook/index.htm

I'm sure you would have tried dry ice and then slipping it out if possible?


"John Martin" wrote in message
oups.com...
I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?

John Martin

just like Wayne said , also you can just walk a tig puddle around the id of
the bearing without adding any filler , quench and listen for the clink as
it falls on the floor

John Martin wrote:
I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?

John Martin

IF You can get to the backside of the race where the flange is hiding
the back of the beating, Take an end mill & make 2 holes in the flange
big enough for whatever size punch you use to drive the race out..you
don't need 360° support for that bearing anyhow !!

Failing that, I have blown them out w/ an acetelene torch---the brgs are
High carbon steel & usually blow out w/o nicking the support metal--
it's uasualy low carbon steel & won't get hot enough to burn out while
you're doing the race. Jerry
usually

Cut a slot in the race perp to the bearing axis with an o/a cutting
torch. Done properly, you won't cut into the parent metal.
JR
Dweller in the cellar


John Martin wrote:

I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?

John Martin



--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth
If you're not the lead dog, the view never changes
Doubt yourself, and the real world will eat you alive
The world doesn't revolve around you, it revolves around me
No skeletons in the closet; just decomposing corpses
--------------------------------------------------------------
Dependence is Vulnerability:
--------------------------------------------------------------
"Open the Pod Bay Doors please, Hal"
"I'm sorry, Dave, I'm afraid I can't do that.."

"John Martin" wrote in news:1129592760.888899.110050
@g43g2000cwa.googlegroups.com:

I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?

John Martin



A slight dab or 5 of liquid nitrogen would have brought it right out,
most likely.

--
Anthony

You can't 'idiot proof' anything....every time you try, they just make
better idiots.

Remove sp to reply via email

"Anthony" wrote in message
...
"John Martin" wrote in news:1129592760.888899.110050
@g43g2000cwa.googlegroups.com:

I needed to remove some ball bearings from an old power brush I'm
rebuilding. The outer race was hidden by the shoulder on the plate
it's mounted in, so I couldn't drift it out. I broke out the inner
race and tried grinding a notch in the outer race with a Foredom-type
grinder and a pink stone, which was taking forever.

I had some solid carbide end mills, so I mounted the plate in the mill
and used the mills to cut into the race. Pretty quickly found that,
even though the mill is fairly heavy, I had to lock the table down.
It's not really a great way to do it, though. The mill is a
horizontal, which means I'm working on the backside of the piece. And
I broke two endmills. Finally got through the race, but nicked the
housing a bit.

There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?

John Martin



A slight dab or 5 of liquid nitrogen would have brought it right out,
most likely.

I have been wondering how well a product called "dust off" would work. It's
made for cleaning out computer cases. Any way one time I turned the can
upside down and sprayed a little in my hand. Not a bright thing to do. I had
a spot of frost for about 15 seconds. I thought man you could freeze a
bushing and drop it in with this stuff. I haven't tried it yet, but about a
15 seconds spraying on the tang end of a number 3 morse taper and I had
frost. Any one out there try that yet?

Wayne Cook wrote:
There must be a better way. Have been considering picking up some
carbide burrs for the grinder. Will these cut through hardened races
quickly? Any better choice of grinding points?


In this situation the best method is to weld a bead on the inside of
the race. I prefer 7018 stick for this but any welding process will
work. The main key is to get the race red hot fast and let it cool.
Once cool it will fall out of the bore. Larger bearings will require
more than one pass.


Wayne Cook

I tried heating with o/a to soften, although the carbide mills didn't
seem to need it. It sounds as though it's not the heat, but the hot
bead shrinking as it cools that does it.

Has anyone used the carbide burrs on something as hard as bearing
races?

John Martin

No room for a conventional bearing puller? They've got some now for
blind holes that can slip between the inner and outer races and pull
bearings out that way. See the MSC catalog. You do have to have a
foot or so working room on the outboard end. A pilot bearing puller
might work and can be rented or even borrowed free from Autozone and
the like.

I guess I'm having trouble picturing your exact setup. If you can't
pull the bearing out because there's something in the way of the bore,
how can you press the new one in?

Stan

wrote:
No room for a conventional bearing puller? They've got some now for
blind holes that can slip between the inner and outer races and pull
bearings out that way. See the MSC catalog. You do have to have a
foot or so working room on the outboard end. A pilot bearing puller
might work and can be rented or even borrowed free from Autozone and
the like.

I guess I'm having trouble picturing your exact setup. If you can't
pull the bearing out because there's something in the way of the bore,
how can you press the new one in?

Stan

This bearing was really in tight, with some rust helping things. Think
of it as being in a blind hole. The shaft goes through, but there
wasn't much to hit to drive it out. I know the pilot bearing pullers
with the expanding fingers, but don't think one would have budged this.

Pressing a new bearing in is easy. I don't have a hydraulic press, but
could get it in with a screw. Or take it to the machine shop and use
the press.

What I was really looking for was an idea of how well the carbide burrs
work.

John Martin

On 18 Oct 2005 12:02:28 -0700, "John Martin"
wrote:


wrote:
No room for a conventional bearing puller? They've got some now for
blind holes that can slip between the inner and outer races and pull
bearings out that way. See the MSC catalog. You do have to have a
foot or so working room on the outboard end. A pilot bearing puller
might work and can be rented or even borrowed free from Autozone and
the like.

I guess I'm having trouble picturing your exact setup. If you can't
pull the bearing out because there's something in the way of the bore,
how can you press the new one in?

Stan

This bearing was really in tight, with some rust helping things. Think
of it as being in a blind hole. The shaft goes through, but there
wasn't much to hit to drive it out. I know the pilot bearing pullers
with the expanding fingers, but don't think one would have budged this.

Pressing a new bearing in is easy. I don't have a hydraulic press, but
could get it in with a screw. Or take it to the machine shop and use
the press.

What I was really looking for was an idea of how well the carbide burrs
work.

The problem there is that there's a wide range or burrs and driving
methods. The dremel carbide burr works ok on smaller stuff especially
if it's soft but it's not real good on hard from my experience. My big
burrs in my die grinders will cut hard steel some but will tend to
dull more in it at the high speed that they run.

Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook/index.htm