Highest speed needed for a wood lathe

[Doug Walls]

I'm in the process of rebuilding an old 12” X 48” Fay & Egan flat-belt lathe, It originally had a 4 step drive pulley connected straight to the motor. My plans are to put a 4 speed Drive-All gear-box in the same location as the original motor, Then the gear box will be belt driven from a motor mounted below the lathe.

The gear box originally came off of a South-Bend metal lathe & has a ratio of ruffly 1:1, 2:1, 3:1, 4:1, There's an 8” pulley on the gear box & a 4” pulley for the motor. If I kept this same pulley ratio I would end up with about a 2400 RPM high speed & about 80 RPM for a low speed.

Being that the pulley size's & ratio from the motor to the gear-box will delegate the highest speed achievable. I'm trying to figure out what ratio would be best to use to get the highest speed needed?

My main use of the wood lathe will probably be mostly for 2” X 2” or larger table legs & bowls, So I doubt I would really need anything over 2400 RPM?

Doug

[Eric Holmquist]

From your description of intended use, there is no need to go over 2400. Typically only small diameter turnings benefit from much higher speed, and even then that speed is fine. You want a nice low RPM which you are getting at 80 RPM.

[Thom Sturgill]

I greatly disagree. The late Dale Nish had a formula for turning speed:

RPM = 6000/D to 9000/D where D is diameter in inches.

For 2" stock this means speeds between 3000 and 4500 rpm. Now if you were turning bowls the speeds you mentioned would be great. An 8" bowl would turn between 750rpm and 1125 rpm. As a sometimes spindle turner I have had my lathe at its maximum rpm several times. By that formula, you probably would not want to turn anything much under 3". The key is how many feet of surface pass under the blade per minute for efficient cutting, not what the absolute rpm is.

[Reed Gray]

You might want lathe speeds up to 3,000. Just starting out, 2400 would be fine, and quite workable, but after a while, if you had a lathe that would go faster, and tried it, you would like the higher speeds better. Having the slow speed of 80 or less is great for sanding.

robo hippy

[Doug Walls]

Thanks for all the reply’s!

Sounds like I should be able to set it up as is for now, At least until I get a little more experience with it.

Doug