Pressing A Bench Grinder Spindle Back To Spec

Ozwelder

Active User
Registered
Joined
Oct 15, 2011
Messages
153
I have a 8" 1 HP bench grinder that had something fall on it when in storage.As a result the spindle suffered a bend about where it exits the case. Dial indicator says .012" run out.

It was a Taiwanese bench grinder but good quality for its day as it is about 30 years old and before its accident was good performer and would run on for a couple of minutes after switch off.

I can disassemble to the stage where I can put the spindle with attached rotor under a hydraulic press in vee blocks.
Is the best way to straighten the shaft or is another way recommended?

Thank you

Ozwelder
 
You got it. That is the way I would do it.
 
.012 inch is about the maximum I would straighten as above. Even here, I would
check the point of bend with a drop of dye and a good magnifying glass....BLJHB
 
I would check the point of bend with a drop of dye and a good magnifying glass....BLJHB[/QUOTE said:
Ok, maybe a noob question, but why the dye ?
 
If a stress crack is starting ( very dangerous! ) the dye will seep into
the crack and make it more visible.......BLJHB
 
.012 inch is about the maximum I would straighten as above. Even here, I would
check the point of bend with a drop of dye and a good magnifying glass....BLJHB

Ah hah! potential cracking ! Something I should have thought about! I am fortunate to have once worked in NDT and have access to some die check and developer.

Many thanks for the replies.
 
Is it possible to machine out the 0.012" and fit the stone/wheel on that side with a slightly bigger spacer?
 
The press should work fine. The 5 hp 3ph motor that came with the rpc I have for my mill had a bent shaft. I was able to get it almost perfect with out much effort. Mike
 
Is it possible to machine out the 0.012" and fit the stone/wheel on that side with a slightly bigger spacer?
Trim to "straight"shrink on a thin sleeve ( wheel andwashers length,true up threads)
Get experienced help on site....... BLJHB
 
I wouldn't even tear it down. Mount it securely, find a long enough piece of close fitting tubing and bend it by hand. It's already in the bearings it will run in, so better than vee blocks. Should be able to get it plenty close.
 
Back
Top