Truing up an arbor hub taper

[jmhoying]

I picked up a "personal" surface grinder the other night (identical to Grizzly 6x12"). Although mine is a 2008 model, it was stored in a shop since new and never assembled. Overall, it seems really nice (for a home shop unit), but I noticed that the wheel had a sideways wobble to it. I removed the hub and checked the spindle run-out, and it was about 1/2 a thousandth, so that wasn't the problem. With the hub mounted, I put an indicator on the wheel mounting face and there was about .015 run out. I removed the hub, cleaned everything up and remounted it, only to have about .025 run-out this time. I was guessing at this time that the hub taper was incorrect, so I blued the taper and pushed and spun the hub onto it. Turns out that the only contact area is in the last 15% of the small end of the taper, so it looks like I'll have to fix up the hub taper on my lathe. I've never done a project like this, but I'm thinking that once I have the hub chucked in perfectly, I'll have to dial in the compound to get the exact taper that I need for the internal bore. (from what I gather, it's a 7.5 degree taper, approximately 1.5" long)
Am I thinking along the correct lines to attack this problem? As is, the hub is already scrap, so I'm not out much in case I really mess it up.

Jack

 

[Ulma Doctor]

you can chuck up the part and indicate the bore to make sure bore is true and then set up to take a light cut .
re-blue and recheck!!

You can't mess something up that's already messed up!

if nothing else you'll get to mess with your other tools to fix another tool,
to me that's fun)