This is the poor mans tool post grinder. It is a 6 inch 1/3 HP $45
dollar bench grinder from harbor freight.

Makes a super smooth cut but it takes about 2 hours to get off the
unneeded 3/4 inch on the ring gear. You will save a pound.

Cutting it with a carbide tool creates a fire.

That ring gear is super hard.

If you flame cut it off it will soften it.

A laser or water jet might do it but I haven't tried that yet and it
could be expensive.

It will also work to get rid of the unneeded teeth on the sun gear.

Paul Lamar


Hi Paul, Glad to see the ways covered...if you have a 4" grinder
about put a cut off wheel on it and attach it to the cross slide. The
cut should take only minutes and maybe burn up 2 wheels. The pictured
grinder will finish up nicely. As you have already done. Way to get
er done. Michael Nash


That sounds like it will work. I'll try that on the next one. What
amazes me the part barely gets above room temperature.

In this picture you can see the dust particles curving to go in to
the vacuum hose :-)

the finish is suburb.

Paul Lamar

I made an attachment like that that fits my table router I made
several years ago I used to Harbor Freight 3/4 horse 8 inch wheel
Grinder. And yes surprisingly enough the Finish turned out great and
since it's a CNC router table I just program it to go down .0005 make
a full pass over the surface then go back to the diamond Tool surface
the wheel I repeat passes. Surprisingly it gave me a pretty good
finish on some steel parts.

David Mikesell San Jose , CA

Are you going to be home soon David? I have a lot of questions :-)

Also we need a rotor head dinner in your neck of the woods :-)
There is Simon S and Dave J so far.


Paul Lamar


I hope so. I am working on a Puma 350B right now that looks like it was put together with parts from 8 different machines....it is a mess. Today I aligned the spindle assy, it came back from rebuilding Friday. It went so fast and got it within .000025 over 9 inches on the first setup and no taper over 9 inches. When I am done it should make beautiful parts.

I do so love this work, it is just fun!

David Mikesell

How in the heck do you measure that :-)

Paul Lamar

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