Belt grinder build questions

[Ironman]

I an slowly pecking away at a belt grinder that I want to be 6" x 48" on a Bill Pace design.
I have a 5hp motor at 3450 rpm that the backbone bolts to.

My plan is to bore a 5/8" hole in the 1" shaft the belt driver is on, for the motor shaft and broach a keyway to drive the roller.
My question is should I hang the 7 inch drive roller off the motor shaft, or should I use an outboard bearing on the other end. Reason says that it should be able to be hung off the motor shaft, but there may be enough flex to cause vibration and belt walking.
So I am leaning to using an outboard pillow block bearing. Any ideas as the best way to set up direct drive on this could be useful.

[tackit]

This probably is no help to you, but my 2 1/2" Ellis's drum comes right off the motor. I have no vibration problems.

http://www.ellissaw.com/wp-content/u...2-22-14_BG.pdf

Those are some nice grinders your looking at.

http://www.cnccookbook.com/CCKnifeMakingGrinders.htm

[digr]

Your 5 HP motor only has a 5/8" shaft? How much shaft do you have left after the back bone?

[digr]

5/8" shaft 4"X 7" driver

[weldor2005]

Originally Posted by digr

Your 5 HP motor only has a 5/8" shaft? How much shaft do you have left after the back bone?

I thought the same thing. I would expect issues with the shaft. For sure if you don't support the other end, then that shaft will get bent. I thought that most 2HP motors were at least 3/4" shafts..

[milomilo]

Are you using a 2 or 3 pulley design?

[digr]

Originally Posted by milomilo

Are you using a 2 or 3 pulley design?

The Bill Pace design is a two pulley

[Ironman]

Originally Posted by weldor2005

I thought the same thing. I would expect issues with the shaft. For sure if you don't support the other end, then that shaft will get bent. I thought that most 2HP motors were at least 3/4" shafts..

This is a 3450 rpm and they are small shafts on these motors. The 1750 rpm motors are 3/4 or up to 1.125
I have a 6 inch belt grinder now that is hung outboard and from one 2 inch long arbor and a 1" shaft.
Belt tension is not a big deal, it is light.

Originally Posted by digr View Post
Your 5 HP motor only has a 5/8" shaft? How much shaft do you have left after the back bone?

About 2.75", it is a c frame so the face is recessed from the bearing surface and the backbone is 3/8" plate so the motor protrudes 1/2 way through the bone

[digr]

You might be alright if your pulley runs true and is balanced.

[Ironman]

Originally Posted by digr

You might be alright if your pulley runs true and is balanced.

Yes, well....hmmm I hope so. I know it is true in the lathe, I guess I'll have to try it to find out.