Question for Peter Nap: size of fiberboard wheels??

[RokJok]

Peter, I archived your posting below about cleverly making sharpening wheels out of fiberboard. For some reason the search engine can't find it for me , hence this new thread. Medium density fiberboard (MDF) was the "fiberboard" that was used to construct the wheels, if I understand it correctly.

My two questions are:
1. What is the final diameter of those wheels?
2. What RPM do you run them at?

Thanks for sharing that ingenious idea.
-- Greg --

peter nap
Location: dunkle hollow, Va., USA
03-14-2004 02:13 PM

It Really Sharpens
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I've tried a bunch of different power sharpening methods. The latest was the cardboard wheel. It worked. Didn't like it for no good reason.

I am the king of dull chisels. I have dozens. I had a lot of woodwork (stock) to do last night and all my chisels were worse than dull.

Not having any desire to sharpen even one by hand, I started thinking. This is a somewhat dangerous process for me. Especially late at night.

What to use to make a sharpening wheel that will mirror polish fast and not roll the edges over or burn the steel. I saw a 4X4 sheet of fiberboard left over from a project years ago. I cut two wheels, glued them together, mounted them on a 1Hp motor and started it up.

After a minute with a rasp truing it, I charged it with white Rouge. I got one chisel that was fit to ride to Jerico on and 30 seconds later has a mirror polish on the entire bevel. Real world time. I took a 1200 grit slip stone and ran it down the back to get rid of the wire edge (there wasn't much of one for some reason)

Picked up a block of wood and started cutting. The sound was amazing. When it cut it went schhhhh, instead of crack.

Next I got one of my shop knives that I keep in case I need to BEAT someone to death. Less than a minute and it was shaving hair. I was having so much fun I didn't get any stock work done at all but I sharpened every chisel I own.

This thing really works!

 

[peter nap]

The two questions are related to a certain extent! The larger you make the wheel, the faster it spins so the slower you make the motor.

There is a simple answer though. First, this does not requite great power so the faster speed/lower torque is OK.

To make it, get a motor first. Make the wheel large enough to clear the top of the motor and some to spare. This way you can sharpen things like knives, without tilting them to clear the motor housing.

End of measurements. Simple enough, isn't it

The speed is what really does the work but don't drive it so fast that it's dangerous.