Done any sweat fitting latley?

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Ever got one stuck? how bad does that suck! I got a 3 inch pin stuck in a 3 inch bore once not long ago fixing the pivot on a giant hyster forklift, ended up have to machine that one out. i've sorta learned the hard way. If in doubt KEEP HEATING IT!
Reply:thumbs up!i.u.o.e. # 15queens, ny and sunny fla
Reply:The trick is to heat, walk away and grab some coffee, heat again, then fit.  Where a lot of people make the mistake is to heat the bore from the inside.  Most interference fits can be overcome by 250 degrees F.  A good test is to spit in the bore,  if the ball of spit rolls off the other side you are hot enough.  The trouble is.  If you have heated from the bore, by the time you fit the shaft the bore has already cooled.  You need to heat from the outside of the hub until the bore is 250 F.  Most of the shafts I deal with are 6-10 inches.  You only get one attempt per day to mount.  If you get it wrong you have to wait a day to cool before you can attempt to mount again.
Reply:Mmmm I wish we had coffee at work! I never know what temp thing really start to grow at I heat it untill its damn near glowing. I just dont take the chance.
Reply:Originally Posted by jesusno2Mmmm I wish we had coffee at work! I never know what temp thing really start to grow at I heat it untill its damn near glowing. I just dont take the chance.
Reply:Temperature crayons work best.  250 degrees will open up a .003-.004" interference fit easy.  The other trick is to measure the shaft with your outside mic, then set your inside mic to that dimension +.003" and heat until the inside mic passes freely.  At that point you are ready to mount.When mounting bearings, I just set the oven to 275 and toss them in for 40 minutes (this is still safe for rubber sealed bearings).  Then they just slide right on the shaft.