Thread: Buffing Setup

Originally Posted by grunto

I have managed to pick up this Buffing Spindle from a steel fabricator that was throwing it out. It was used to buff up stainless steel (you can see the remnants of a buffing wheel on the left hand end). To give an idea of size, the spindle is 1200mm long and 30mm diameter. Unfortunately I did not get the full stand or motor that went with it. A couple of questions that the forum might be able to help with:
1. What speed do you normally run these at? Bench grinders are normally 2800 RPM (I think) - is this the optimal speed for a buffing wheel?

There are plenty of metal buffing speed charts on the web.
eg http://www.schaffnermfg.com/engineers-speedchart.php
Typical specs are presented as linear speed (feet per minute) with values between 6 and 9000 fpm being quoted for different processes and metals.
8" wheels on the ends of 2800 RPM grinders are typically too slow especially as the wheel wears.

The FPM depends on the size of the wheel, the differences in the pulley ratios used and the motor RPM
An 8" wheel can generate 6000 fpm at 2800 RPM but as the when wears then it won't bet at that speed.
To generate 9000 FPM with an 8" wheel you will need 4300 rpm (when the wheel is new new)

One setup possibility would use something like a 2HP 2800 RPM motor, a variable speed drive and a pulley ratio that allows the motor to operate across a suitable RPM range
EG a 1.3:1 pulley would generate 6000 tom at 40Hz and 9000 fpm at around 60Hz.
At those RPM ranges you could even get away with a 1.5HP motor.

3. Has anyone got any suggestions for the stand?

Definitely free standing is better for getting awkward shapes around the wheel.

. Any other things that I should consider (variable speed? reverse direction?).

Variabel speed definitely - see above.
Reverse can be useful BUT then the wheel won's stay on those self tightening spindles.
Maybe look at some other wheel fixing mechanism.

I would not consider a revers function for polishing, that is a recipe for disaster. Most polishing lathes run around 3500 rpm so depending on the size wheel you are going to use speeds from 3000 to 4000 will do

Originally Posted by BobL

There are plenty of metal buffing speed charts on the web.
eg http://www.schaffnermfg.com/engineers-speedchart.php
Typical specs are presented as linear speed (feet per minute) with values between 6 and 9000 fpm being quoted for different processes and metals.
8" wheels on the ends of 2800 RPM grinders are typically too slow especially as the wheel wears.

The FPM depends on the size of the wheel, the differences in the pulley ratios used and the motor RPM
An 8" wheel can generate 6000 fpm at 2800 RPM but as the when wears then it won't bet at that speed.
To generate 9000 FPM with an 8" wheel you will need 4300 rpm (when the wheel is new new)

One setup possibility would use something like a 2HP 2800 RPM motor, a variable speed drive and a pulley ratio that allows the motor to operate across a suitable RPM range
EG a 1.3:1 pulley would generate 6000 tom at 40Hz and 9000 fpm at around 60Hz.
At those RPM ranges you could even get away with a 1.5HP motor.


Definitely free standing is better for getting awkward shapes around the wheel.


Variabel speed definitely - see above.
Reverse can be useful BUT then the wheel won's stay on those self tightening spindles.
Maybe look at some other wheel fixing mechanism.

Thanks for the link - it has a wealth of information. I will probably go with a 2HP 2800RPM motor and use a combination of pulley ratio and VFD to get something in the 6000 - 9000 fpm range. Haven't played with VFDs much so that will be a bit of a learning curve I am sure.

Didn't think about the wheels coming off if the direction was reversed - DOH!!

Will go for a free standing design but space will be an issue so will have to think about that a bit more. Maybe have it on castors with screw down feet?

Originally Posted by grunto

Thanks for the link - it has a wealth of information. I will probably go with a 2HP 2800RPM motor and use a combination of pulley ratio and VFD to get something in the 6000 - 9000 fpm range. Haven't played with VFDs much so that will be a bit of a learning curve I am sure.

Didn't think about the wheels coming off if the direction was reversed - DOH!!

Will go for a free standing design but space will be an issue so will have to think about that a bit more. Maybe have it on castors with screw down feet?

I would think that you might want to tie it down pretty well, as when you lean on it with your work-piece, it might want to walk about like a spin dryer with an out of balance load.

Just my 2c but I have always preferred slower speeds. I'm sure their are correct and better methods, but at slower speeds I find it more controllable.

I guess it depends on what you plan to do with it. If your in a production workshop working on big parts you may want it quick.

A VFD and reverse have always been helpful for me.

They are seriously grabby tools! Many times I have flung what I was working on across the workshop...they can get pretty dangerous if your not paying attention. That has happened mostly on my smaller buffing wheels on a regular 8inch bench grinder.

On my regular setup I run 300mm buffs at (I'm guessing as I built the machine a long time ago) half the speed of a normal bench grinder. I also built it with normal RH threads as at the time, I could not get my head around a L hand thread. It actually has saved me many times over. When a part grabs, it just unlocks the buffing wheel.

I am thinking of initially setting it up with a motor and pulley arrangement to sort out speeds etc and then going to a VFD (which I have not quite got my head around yet). Probably will use 10" or 12" wheels. Will only be for home use.

I grew up in a metal polishing factory and as a metal polisher myself for over 20 years I don't know why you wold want Variable speed. You need speed to polish. Our machines were al 3phase 3,4,5 Hp motors running at 3500 rpm. We ran 12inch or 14inch wheels on them all the time and for small jobs we used smaller wheels.

Originally Posted by george mavridis

I grew up in a metal polishing factory and as a metal polisher myself for over 20 years I don't know why you wold want Variable speed. You need speed to polish. Our machines were al 3phase 3,4,5 Hp motors running at 3500 rpm. We ran 12inch or 14inch wheels on them all the time and for small jobs we used smaller wheels.

I agree more speed is needed but there is an optimum speed range for polishing different metals. Prior to the availability of easy/cheap speed control of machinery polishing shops would just run their buffs at one speed.

Here is a typical chart for polishing different metals from http://www.schaffnermfg.com/engineers-speedchart.php
The SFPM chart shows that a 12" wheel at ~3500 rpm will generate ~11.000 SFPM this covers all cases for different metal and allows for wheels to wear smaller and still be in the SFPM ball park