question about sheaves and shafts

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hello everyone,looking for inputs about sheaves. I have the electric motor off my bandsaw, and gear reducer. My pocket caliper says the main shafts are both 5/8 of an inch. I cannot discern any plus or minus, they both look dead on the same. One is keyed with a 3/16 inch and the other with 1/4' key. The pulley off the motor should fit on the reducer, but it doesnt. Its like its a 1/32 difference. If I were to use a 4 pound beater, I could get it on there, but of course I dont want to do that.So is there a "nominal" in the production of shafts? Wondering if I order more sheaves, will they fit the shaft on the motor?  Would I be able to clamp a sheave down on a drill press table and take off another 1/64 -1/32" from the bore?Also, the output shaft on the reducer is coming in at 13/16'. If been unable to find anyone selling sheaves with that size bore.hey, big weekend coming up, everyone stay safe. Attached Images
Reply:A shaft 0.6250 won't fit in a hole of 0.6248.  Well, not without force.  Seriously, if you need something to fit with precision, then you have to make and measure it to precision.And no, a typical drill press can not usually do that sort of precision.  Especially not with a "drill".A "reamer" is a tool-of-choice to precision machine a hole to the desired size.Also, you -could- have some metric-dimensioned parts in there.All that said, 5/8 inch diameter is a pretty 'standard' size for motor shafts and pulley bores.  Double-check that there isn't a burr somewhere or a bit of corrosion.  It often doesn't take much to change parts from 'fits' to 'dont-fit'.A shaft of 13/16 inch is not as common as say one of 3/4  or 7/8 inch, but it still is a 'standard' size.  That 13/16 -could- also be 20mm, depending on how well you are measuring things.  The best laid schemes ... Gang oft agley ...
Reply:Getting the pulleys on is just a matter of a little heat..If they measure the same on the calipers there is NO WAY that they are 1/16" different..What are you gonna do about the 2 different key sizes is my question.....zap!Last edited by zapster; 09-03-2010 at 03:36 PM.I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsterGetting the pulleys on is just a matter of a little heat..If they measure the same on the calipers there is NO WAY that they are 1/16" different..What are you gonna do about the 2 different key sizes is my question.....zap!
Reply:I make my own sheaves and such..It's what I do..If you need anything machined let me know.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:I'll 2nd that on a little heat. It's common for pulleys, sprockets, gears and bearings to be a light drive or press fit. Also with cheap die cast pulleys this could even be due to production tolerence. You really wouldn't want a slip fit. In a pinch and lacking a broaching set at the time I've cut keyways with a mini hacksaw and files. Sometimes stepped keystock is available. Sometime pulleys can be found at old school full line hardware stores but your best bet is to look in the yellow pages under bearings or power transmission. Online you can most likely find what you need at Mcmaster.com. Use Grainger as a last resort because it will cost the most there. For something totally custom see above post.Tough as nails and damn near as smart
Reply:I make my own keys. I have always make keys with 2 different sizes on them. Just made some for the neighbor with a 1/4" bottom and a 3/16" top. Thats where my little shaper comes in handy...BobBob WrightSalem, Ohio  Birthplace of the Silver & Deming Drillhttp://groups.yahoo.com/group/southbend10k/http://groups.yahoo.com/group/sawking/1999 Miller MM185 w/ Miller 185 Spoolmate spoolgun