View Single Post
  #5   Report Post  
Posted to rec.crafts.metalworking
[email protected] dcaster@krl.org is offline
external usenet poster
 
Posts: 3,984
Default More 4140 questions

On Apr 12, 7:07*pm, "Terry Coombs" wrote:
* Almost finished with the part ... OK , what this part is *, it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut into
the sleeve , as the nut is tightened the dovetail locks the crankpin to the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing and
the crank plate that mates the shaft to the crankpin . NOW , the question is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...


My gut says it depends on the thickness of the sleeve. A thin sleeve
will stretch . A thick sleeve will not expand as much. But can you
not turn the motor on and use some abrasive to take a little off of
the sleeve diameter?


Dan