Press Fit Slipping

+1 on 4gsr, if you put the cast in the freezer, and heat the brass in the oven to about 300, then it will be relatively easy to put the band on. Then let the temp equalize and then machine. If you really want it to stay also use a little Loctite on it as well.
I often use that method for brass and cast or other steel parts. you can use more interference that way.
 
I do a recurring job of 50+ parts at a time on drive train components, this is a drive flange with a splined bore where an oil seal rides on the OD, the seal cuts a groove over time and fails. They are forged steel hardened then ground to about RC 50, using a hard turning insert I turn them from 1.875" to 1.75" X .720" length, then turn 304 stainless sleeves with a bore of 1.746- 1.747" then press them on and turn to 1.878-1.879". I have done 500+ of these in the last 2 years and not one has spun or failed failed in use, no heat and no loctite. We bore the ID with a 1.755" X .050 deep counterbore which causes the sleeve to start squarely before the pressing operation, this works a charm and looks like this.
sleeve_zpsiovor8te.jpg
 
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Cool. Thanks for the real-world example with measurements. I especially like that counterbore alignment technique. [*makes mental note*]
 
intjonmiller said:
Cool. Thanks for the real-world example with measurements. I especially like that counterbore alignment technique. [*makes mental note*]
Click to expand...
The hard turning generates some hot chips. The uncut part is an aluminum center plug that uses a live center to push the part into a step machined into soft jaws which keeps the parts from leaving the chuck towards your head, I have flung several of these parts out out of the chuck when to lazy to use it.

If you cut through the case into the unhardened core it will ruin the insert in seconds, also no coolant used.

http://s1378.photobucket.com/user/wrecktm1/media/0000hub8_zpsudsdbkps.mp4.html?o=22
 
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I make press-fit stuff all the time, you have to measure at room temp.

I make aluminum rings to fit a mill spindle for measuring the RPM of the spindle. I have to put the ring on a vise to put it on the spindle for the final finish which is done with a Scotch-Brite™ pad. I can get the pad to heat the ring up enough to slip it off when it's done.

I'd have to hone them .0001-.0002 over if I wanted to retain enough red Loctite to do the job. Knurling would give the Loctite a way to stay were it's needed. If you don't do one or he other all the Loctite is pushed out and nothing is left to stick.
 
Shrunk (?shrink?) fit the brass band onto the flywheel.:congratulate: .0045 shrink fit. Heated with the propane torch and lightly tapped them together for a very good fit.:chemist: Machined it afterward with no problem. Still have to turn a .250 diameter pin for press fit through the center of the flywheel.
Thanks for all the response and suggestions.:danke:
 
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