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
A lot aren't removable these days. A replacement armature may be the answer. If the problem is brush wear just replacing the other one may suffice. A drop of lubricant may sufficiently prolong the life of the drive end one.
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 =A33.50 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.
Have something to add? Share your thoughts — no account required.
Ask the community — no account required