I've no doubt there are lots of other questions, so I didn't make the
title too specific, though I have a specific problem.
One of the motor bearings has gone on my old Bosch V454. No problem
with the bearings as they are a standard size. To change them I need to
get the drive roller off. Anyone any idea how it is fitted? There is no
set screw, or sign of a keyway. I guess it is threaded on, but which
hand? Maybe it is locked a bonding agent, or heated into place. Anybody
know?

Thanks

wrote in message
.com...
I've no doubt there are lots of other questions, so I didn't make the
title too specific, though I have a specific problem.
One of the motor bearings has gone on my old Bosch V454. No problem
with the bearings as they are a standard size. To change them I need to
get the drive roller off. Anyone any idea how it is fitted? There is no
set screw, or sign of a keyway. I guess it is threaded on, but which
hand? Maybe it is locked a bonding agent, or heated into place. Anybody
know?

Thanks


More often than not these are shrunk/pressed on (by heating I assume) .
Without some special jaws for a puller, I don't think you will be able to
pull one off. Other times they are welded on - even worse.
Either way it makes bearing changes a real pain. When I thought I was going
have change a motor bearing a year or so back, I was preparing to machine
the pulley off and make a new one to fit on afterwards. However, the Gods
smiled upon the job and it turned out it was the bearing at the other end of
the motor that was shot!

Good Luck

Bob

Pretty sure it's not welded. I have suitable heat sources, can put it
in the freezer overnight then heat the pulley, but I think I'll see if
there is a someone who knows the answer before I take drastic action!

Thanks - Jonathan

Well it's about 20 years old and it clearly is a seperate component, so
maybe not 'These days'.
No, replacing brushes or drops of oil will not help a collapsed ball
bearing race. Looks like freeze the shaft, then heat and pull.

Jonathan

Well, I found out how it goes together, in case anyone else is
struggling with the same prob. There is a retaining ridge at the end of
the shaft. I'm not sure if the 'pinion' is heated up and slipped over
the ridge, or if the ridge is made by spreading the end of the shaft
after the pinion is in place. The shaft diam is 10mm. It is quite soft.
I guess that if you drill back about 1mm, 10mm diam, or slightly over,
the pinion should be quite easy to pull away. If you file a couple of
flats for penetration, loctite will hold it when put back. Easy to
remove again by heating until it starts to smoke a bit.
I tried to remove it by heat and force, and bent the end of the shaft.
I sawed it off and drilled and punched teh shaft out with care, so I
could see what was there.
I found sealed bearings for £3.50 each, so it's worth proceeding. I
will test the motor as is, to make sure nothing else is wrong. I expect
I will use 10mm ground stock to replace the end of the shaft, drill it
back and assemble it all with loctite (an appropriate grade).

I replaced the bearing, rebuilt the motor and connected it up. It runs,
so on to modifying to get teh oinion back on.