I need to replace the rear bearing on my bandsaw as the other one has gone horribly wrong, I realise I need a bearing puller to get the old one off but how do I go about getting a new one (if I can find one the right size) back on - it it just a matter of hitting it on with a big hammer (hammer) or is there some way more scientific than that?!
Replacing bandsaw bearing
- Thread starter Unib
- Start date
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beech1948
Established Member
Ok so first obtaining the replacements.
When you remove the old bearings first note the lettering around the outside or even on the front/rear of the bearing. This will be a manufacturer name and a bearing number. It would be smart to also measure ( digital caliper) the inside diameter, bearing thickness, bearing width etc etc.
Look in yellow pages/yell web site for a bearing supplier in your area. When you call or email give them all of the above data and ask for a quote. Bearings are of standardised sizes and they will find the right size for you even looking through a series of look up tables to find other manufacturers part numbers and sizes.
To get the bearing on the spindle or fitting take the shaft and put it into a freezer for 24 hrs, when you take it out give it a quick wipe down, place your bearing on a lit bulb ( incandescent type) and allow the bearing to heat up for a few minutes...wearing gloves place bearing over shaft and push to engage OR place a piece of wood over the bearing and hit firmly but not a brutal smash and hit it squarely...the bearing should slide on...then with a ready made pipe, plastic or metal or socket or shop made wooden aid( with a shaft sized hole in it press the bearing quickly down the shaft and seat it in position.
DO NOT press on the outer race at all ONLY press on the inner race.
If fitting to a metal cover and not a shaft reverse the heat and freeze approach..that is heat the metal part and freeze the bearing.
Bearings are cheapish so if you mess up not much is lost.
If the above is too risky for you then take it to a machine shop/ engineers or large garage and ask them to press the bearings on for you using their hydraulic press. You might ask the bearing supplier who are their most frequent customers close(ish) to you to find out who is likely to be able to do this.
Hope this helps..I've used this method quite a few times. For more certainty have a look at the OWWM site ( its American) and search for bearing replacement you will find many examples.
Al
When you remove the old bearings first note the lettering around the outside or even on the front/rear of the bearing. This will be a manufacturer name and a bearing number. It would be smart to also measure ( digital caliper) the inside diameter, bearing thickness, bearing width etc etc.
Look in yellow pages/yell web site for a bearing supplier in your area. When you call or email give them all of the above data and ask for a quote. Bearings are of standardised sizes and they will find the right size for you even looking through a series of look up tables to find other manufacturers part numbers and sizes.
To get the bearing on the spindle or fitting take the shaft and put it into a freezer for 24 hrs, when you take it out give it a quick wipe down, place your bearing on a lit bulb ( incandescent type) and allow the bearing to heat up for a few minutes...wearing gloves place bearing over shaft and push to engage OR place a piece of wood over the bearing and hit firmly but not a brutal smash and hit it squarely...the bearing should slide on...then with a ready made pipe, plastic or metal or socket or shop made wooden aid( with a shaft sized hole in it press the bearing quickly down the shaft and seat it in position.
DO NOT press on the outer race at all ONLY press on the inner race.
If fitting to a metal cover and not a shaft reverse the heat and freeze approach..that is heat the metal part and freeze the bearing.
Bearings are cheapish so if you mess up not much is lost.
If the above is too risky for you then take it to a machine shop/ engineers or large garage and ask them to press the bearings on for you using their hydraulic press. You might ask the bearing supplier who are their most frequent customers close(ish) to you to find out who is likely to be able to do this.
Hope this helps..I've used this method quite a few times. For more certainty have a look at the OWWM site ( its American) and search for bearing replacement you will find many examples.
Al
kirkpoore1
Established Member
Al is quite correct. You'll be a little tense on the first one. After that, you'll go "Is that all?" and they'll be easier.
In addition to the bearing inner diameter, outer diameter, and thickness, note whether the bearing has an extended inner or outer race (meaning it's thicker on the inside or outside), and whether it's got metal shields or plastic/rubber seals on the faces. (The bearings could also be open on one or both sides, but that's fairly unlikely unless the saw is quite old.)
Finally, try to avoid Chinese bearings. The quality control is all over the map.
Kirk
In addition to the bearing inner diameter, outer diameter, and thickness, note whether the bearing has an extended inner or outer race (meaning it's thicker on the inside or outside), and whether it's got metal shields or plastic/rubber seals on the faces. (The bearings could also be open on one or both sides, but that's fairly unlikely unless the saw is quite old.)
Finally, try to avoid Chinese bearings. The quality control is all over the map.
Kirk
City seals and bearings are your people for bearings in Sheffield
CHJ
Established Member
As already said, the most important thing is to only apply fitting pressure to the inner or outer race as appropriate depending on whether you are fitting to shaft or housing, you don't want to apply a side force across the bearing race. Dependant upon distance required to push or drive the bearing a suitable socket from a socket set or a box spanner often will do the job. Sometimes with care it's possible to use the old bearing components as a spacer to start the 'push', but be careful not to push to far and jamb the old component on the shaft or in the housing.
To disassemble an old ball bearing race, destroy the race cage, clamp the outer race as hard as possible in a metal working vice with a block of wood below it to stop it swiveling, you are attempting to make the outer race oval, bunch all but one of the balls tight together leaving one in the centre of the jaw gap on it's own, hit this one with a blunt punch to knock it out.
Believe it or not that is the reverse principle of how the balls are put in there in the first place. Some larger races may have a slight scollop in the track rim to aid this.
To disassemble an old ball bearing race, destroy the race cage, clamp the outer race as hard as possible in a metal working vice with a block of wood below it to stop it swiveling, you are attempting to make the outer race oval, bunch all but one of the balls tight together leaving one in the centre of the jaw gap on it's own, hit this one with a blunt punch to knock it out.
Believe it or not that is the reverse principle of how the balls are put in there in the first place. Some larger races may have a slight scollop in the track rim to aid this.
PeterBassett
Established Member
See this thread for an identical problem and solution by yours truly.
bandsaw-restoration-advice-t42613.html?hilit=%20bandsaw
bandsaw-restoration-advice-t42613.html?hilit=%20bandsaw
chipmunk
Established Member
When you know what size you need, these folks are really good...
http://www.arceurotrade.co.uk/Catalogue/Bearings
HTH
Jon
http://www.arceurotrade.co.uk/Catalogue/Bearings
HTH
Jon
Great advice folks, thanks very much. I'd have never of considered putting the shaft in the freezer! I can't read the bearing number off the face because it hasn't got a face left - it's warn away to the bearings. I have a large box of bearings so I'll check through and see if I have a matching one, otherwise I'll give the recommended places a go.
beech1948
Established Member
Unib,
What bandsaw do you have. If you let us know someone else might know what bearings they use or even guide you to a parts list which might also tell you. At worst case you can often ring tech support in the manufacturer and get the info needed.
Al
What bandsaw do you have. If you let us know someone else might know what bearings they use or even guide you to a parts list which might also tell you. At worst case you can often ring tech support in the manufacturer and get the info needed.
Al
beech1948
Established Member
Unib,
Kity went out of business for a while but were resurrected about 2 yrs ago.
NMA were their old distributors and probably still are.
Try them here http://www.nmatools.co.uk/findstockist.asp maybe give them a call. Bearings from them will be more expensive than from a bearing dealer.
Hopefully other people here with a Kity bandsaw will respond with a bearing type for you.
Alan
Kity went out of business for a while but were resurrected about 2 yrs ago.
NMA were their old distributors and probably still are.
Try them here http://www.nmatools.co.uk/findstockist.asp maybe give them a call. Bearings from them will be more expensive than from a bearing dealer.
Hopefully other people here with a Kity bandsaw will respond with a bearing type for you.
Alan
9fingers
Established Member
If you can give me the bearing dimensions, bore x width x outside diameter as exactly as you can measure them, I can look up the standard bearing number and suggest a supplier.
Buying them as machine spares from agents is usually a very expensive way ahead.
Bob
Buying them as machine spares from agents is usually a very expensive way ahead.
Bob
