Shaft and Bearings

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I have a 1" diameter cold rolled steel shaft about 15" long that I am trying to slide through some flange bearings. Due to some seen and unseen minor scratches on the shaft it is next to impossible to slide the shaft through the bearings.Is there a good way to rid the shaft of these scratches? I was worried about using a file and making natters worse.ThanksMillerMatic 212, Lincoln Precision TIG 225, Hypertherm 45XP
Reply:Try emory cloth.- If you can jump across it you can weld it!  - anonymous old boilermaker
Reply:Do you know anyone with a metal lathe? they could clean it up for you. that is the only way I know to keep it straight and remove the scratches on it.Guy_48Welding is an art......Millermatic 252Lincoln SP175PlusLincoln 225 AC/DC
Reply:If it's just scratches and minor marks do as Kangi said, emery cloth.Your best bet is getting it in a roll, tear off a piece 'bout 12-15" long, put the shaft in a vice (lightly) wrap the paper around it and got to town.it's surprising now much you can clean up a shaft that way.....Mike
Reply:Typically a shaft will not slide into a hub; it's usually an interference fit which requires pressure to assemble.If you're sure the shaft and bearing are a matched and correct fit, tiny imperfections of the shaft, like scratches, shouldn't be a problem. Even small nicks and burrs usually don't present an assembly problem when passing over them.Make sure you have correct fit and good alignment. Use a sleeve or driving tool to be sure that assembly forces are absorbed by only the hub or inner race, and are not transmitted through the bearing surface.Depending on the type of bearing/hub/seal some sort of heat (hot oil, hot light bulb, etc.) can be applied to expand the bore's ID to help ease assembly.Not sure what you're working on, but assemblies with more critical fit require ground and polished shaft.Good LuckLast edited by denrep; 12-27-2008 at 01:58 PM.
Reply:If the bearings are C3 then the tolerance will be tighter. If may take some time with the emory cloth before you can slide them on. A little lubrication will help.
Reply:Thanks for the responses
Reply:Have you tried  heating up the flange bearings while cooling the shaft in a freezer ,then slide the shaft through?
Reply:One question is what material is the flanged bearing made of? Sintered, solid brass, steel, etc.. Don't want to be doing too much un-even driving on the flanged bushing by itself for sure.  Another consideration is that the cold rolled itself may not be extremely true. Pretty good, but not perfect by a long shot. Some checking with simple calipers will help varify how true the shaft is along its length. Carefull not to over swell the bushing when pressing it on, carefull not to remove too much material for a hand slip fit . Pretty thin margin there.
Reply:I would try the emery cloth!  I used to work doing HVAC repair and worked with that kind of situation quite a bit.  Many times the bearings had set screws that were in the locking collar and they would leave a bur.  Used emery cloth many times to clean up the shaft to put it back together!Here is what I have so Far:Miller:Shop Master 300 A A/C D/CS 22a Wire FeederRFC-14 Tig PedalHF-251D High Freq. UnitProfax 250 A Mig GunVictor RegulatorsHarris:63-2 torch Cutting Attachment 49-3making home built tig cooler
Reply:Ok, another question from the resident idiot.  What's a damn flange bearing.  Is it like a bearing with a locking concentric collar?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Here's a pic http://tinyurl.com/8xlr62 as opposed to a pillow block bearing http://tinyurl.com/8vgdk8 .....Mike
Reply:Originally Posted by mrmikeyHere's a pic http://tinyurl.com/8xlr62 as opposed to a pillow block bearing http://tinyurl.com/8vgdk8 .....Mike
Reply:Well now, when I saw the mention of flanged bearing, I had mental picture of the conventional flanged bearing/bushing. http://www.smallparts.com/s?ie=UTF8&...FRlRagodkEOCDAThe others I'm used to calling pillow block or flange block bearings.
Reply:That's the type I was thinking of too Sandy and I agree 100% with your post #9 - cold rolled is not very true.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Sandy-  There must be a fine line between bearings and bushings, or I'm not clear on it.  I didn't know those things were called bearings.  I kind of look at them a bushings.  I guess I'm used to rollers etc.  But then I forget about engine "bearings" on the crank.  Pretty confusing"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by duaneb55That's the type I was thinking of too Sandy and I agree 100% with your post #9 - cold rolled is not very true.
Reply:Originally Posted by farmersammSandy-  There must be a fine line between bearings and bushings, or I'm not clear on it.  I didn't know those things were called bearings.  I kind of look at them a bushings.  I guess I'm used to rollers etc.  But then I forget about engine "bearings" on the crank.  Pretty confusing
Reply:Is it a matter of the shaft speed, or the length of the "bearing" surface?"Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by farmersammIs it a matter of the shaft speed, or the length of the "bearing" surface?
Reply:Originally Posted by SandyIn my mind bushings are used for two things, one, to take up excess space, and two, provide some amount of abrasion or wear resistance sometimes both. Bearings are intended leass for filling of space and more for bearing the load of rotating shafts/parts. Most times less crush load than bushings but better wear resistance for higher speed or constantly rotating parts. Still a pretty fine line. An example might be a bushing for a backhoe pin and a bearing for a crankshaft. Similar material, different goals.
Reply:Originally Posted by farmersammI think I see what you mean.  The bushing bears a heavy load on a limited portion of the inside diameter at any one time without causing the pin to wear too much.  The bearing spreads a higher speed load over the entire inside diameter distributing wear evenly on the shaft while holding deflection to a minimum.Damnit i hope I'm getting closer to this
Reply:You've been awful damn patient.Thanks.I get a little weird over this stuff, but it's important to me.  It's something I need to know."Any day above ground is a good day"http://www.farmersamm.com/
Reply:makes sence to me good job guy always wondered that myself.
Reply:Transmissions and the pilot bushing or barring. For years I only knew of bronze pilot bushings then I got into German stuff and found they use roller barrings. I think it also has to do with the cost of manufacture and the quality of the end product.Just something to check, but measure your shaft with a good set of calipers and make sure it is infact a 1" shaft.  I have seen 25mm shaft get mixed in with one inch and is just a touch larger than 1" but not so much it's easily visible by the eye.  If it is 1" then clean it with emory cloth and it should slide in.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:....1"CRS....1020?....a tad tight for the hard cased steel flange bearings of they are balls.....file is OK, fine teeth, single cut....12" works good for me, and you can lay a strip of emory on the file....cleans up most shafts...   TGP shaft should slide through....but snug....use a bit of never-seize....  I've been in the machinery/maintenance/welding a loooooong time.....keep a good supply of files....more usefull than emory most of the time...don't scrimp...good files are $12-15, or more each....and use a handle to avoid the annoying holes you'll get poked in your palms....  Even in a lathe....file will give nice finish....and stay more true than emory strip....I mainly use emory for a fine plish...#320 or 400...Dougspair
Reply:flange bearings also come with the same ball bearings as pillow blocks with and without eccentric locking collars.