Bench Grinder Buffing Wheel

[Krakenfan69]

Looking for infomation on the correct kind of wheel to use with a bench grinder to make a buffing wheel. I have a cheap 6" grinder that I was planing to convert to this task. i am not sure if there is an adapter needed, if there is a compund to add to the wheel or what. Does anyone have any links or relevant info in setting one up for polishing small wrist cuffs and such?

Thanks,

Kraken Fan #69

[Thor]

In Canada my first stop would be Princess Auto. They should have all you need. Check it out here http://www.princessauto.com/en/b/workshop/metal-fabrication/powered/stationary-equipment/bench-grinders/N-tk8m9u?Nrpp=45&No=0

[Nuttish]

2x http://www.amazon.com/Motor-Extension-Grinder-Polish-Buffer/dp/B000OVNQXI + 1x http://www.amazon.com/Piece-Jewelers-Polishing-Compound-Assortment/dp/B0143B7I1A/ref=sr_1_1?s=home-garden&ie=UTF8&qid=1450108360&sr=8-1&keywords=buffing+compound+assortment

Edited December 14, 2015 by Nuttish

[ChriJ]

Nuttish,

Thanks for posting the link to arbor extension. Ive been looking everywhere for one but was mistakingly calling it a mandrel...

no wonder I couldn't find it..

Chris

[Greenwood]

Krakenfan69, Hi

I agree with Thor, the Princess Auto 8" kit is presently on sale and is complete. They also have a 6" kit which would preclude removing the guards.

Good luck

Layo

[Greenwood]

I forgot to mention to check the size of your shaft, the 8" kit fits a 5/8 shaft while the 6" is for 1/2". I suspect your 6" grinder has a 1/2" shaft.

Layo

[Krakenfan69]

Thanks guys. I'll check Princess Auto out.

Kraken Fan #69

[Nuttish]

I forgot to add that bench grinders are ~3500 RPM, which is too fast for burnishing leather IMO.

This is a lot more than you asked, but it's a relatively cheap way to get a more suitable machine burnishing setup and you can continue using your bench grinder as a motor:

Someone at Campbell Randall told me about the merit of burnishing at slower speeds using their various Italian wheels. I use a single phase 1/3 HP motor on a 4:1 pulley connected to an arbor mounted vertically so I can switch wheels out on the top and bottom. In addition to $30 worth of salvaged materials, I needed appropriately sized reducing bushings to fit the wheels to my arbor. I replaced the bearings with babbitt metal. You can get thermally weldable urethane belt material by the foot at McMaster so you don't have to spend hours finding an off the shelf belt.

An easier setup would be a cheap 3 phase fractional horsepower motor and cheap VFD so you can run it on single phase 110 with speed control, which you can't get with a single phase capacitor start motor. This would have been easier to fabricate than my setup because it wouldn't require machining the tensioner/mounting bracket that you can see in the picture. You could make the same thing out of wood with a table saw and router.

[WoodsideCo]

On December 30, 2015 at 0:20 PM, Nuttish said:

I forgot to add that bench grinders are ~3500 RPM, which is too fast for burnishing leather IMO.

This is a lot more than you asked, but it's a relatively cheap way to get a more suitable machine burnishing setup and you can continue using your bench grinder as a motor:

Someone at Campbell Randall told me about the merit of burnishing at slower speeds using their various Italian wheels. I use a single phase 1/3 HP motor on a 4:1 pulley connected to an arbor mounted vertically so I can switch wheels out on the top and bottom. In addition to $30 worth of salvaged materials, I needed appropriately sized reducing bushings to fit the wheels to my arbor. I replaced the bearings with babbitt metal. You can get thermally weldable urethane belt material by the foot at McMaster so you don't have to spend hours finding an off the shelf belt.

An easier setup would be a cheap 3 phase fractional horsepower motor and cheap VFD so you can run it on single phase 110 with speed control, which you can't get with a single phase capacitor start motor. This would have been easier to fabricate than my setup because it wouldn't require machining the tensioner/mounting bracket that you can see in the picture. You could make the same thing out of wood with a table saw and router.

Nuttish-

Really like your setup! Are you using the AP style wheels from Campbell? If so where did you find the proper bushing setup? Having a hard time sourcing them for my motor. My arbor is 5/8" and CR's site says that the bore diameter for their wheels is 20mm. I Am looking into getting a bushing setup machined out for me but would prefer to buy something pre-fabbed  if possible. 

[Nuttish]

I machined the bushings. This setup worked but was too primitive and clunky. 

I would forgo messing with a buffer if you can build the following:

An eBay 2.5 HP DC treadmill motor (<$75), bridge rectifier (<$1), and cheap VARIAC from Amazon Prime (<$15). This allows you to use the motor from ~2200 RPM to a snail's pace. For an arbor, you can sand a left handed 1/2-13 nut halfway down, screw it to the bottom of the spindle threads and use heavy fender washers and another left handed 1/2-13 to sandwich your wheel. You can make a reducing bushing for CR wheels from a piece of Home Depot 1/2" ID 3/4" OD vinyl tubing (<$0.25) cut slightly taller than your wheel so that everything gets held snuggly when you tighten your top nut and smash/expand the tubing (like the rubber spindle that expands to hold a sleeve on a spindle sander).

These motors produce a high amount of torque at all speeds and are intended to be run under load at low speeds without overheating, so they're basically indestructible for this application if you take care to keep dust and debris out of the windings. 

Properly mounted, this machine reproduces the functionality of a European single wheel machine that costs thousands, but is more adjustable, costs less than $150 to build, requires minimal electronics and wood shop experience, and no machine tools. 

[bikermutt07]

Treadmill motor, good thinking.

[WoodsideCo]

Nuttish- Thank you for taking the time to write that up. Really awesome. I will report back when I am able to get the supplies you cited and have the time to get everything set up correctly. Thanks again.

-Sam