lathe speed

[Harry Goodwin]

I always have kind of been able to choose a speed for my bowls on my midi but yesterday I was turning small finials for a ornament and wondered at the maximum speed to run small 1" spindle between centers and my g3 nova chuck. harry thanks

[Scott Hackler]

Harry, speed/rotation is relative to the diameter of the wood being turned. The smaller the diameter the faster the lathe could/should be running for efficient cuts. While doing my finials I have my lathe at 2000rpm or so. That works well for me and the end result requires less sanding. The most important thing is to know your personal limits and turn safely.

[Reed Gray]

The old saying about 'what speed you are comfortable with' works here as well as with bowls. Most of the time, spindles and pen type things are turned at higher rpm than bowls because of size. So for small finials, 2000 or so is common, if you are comfortable with it. The feet per minute rate is probably about the same as a much larger bowl.

robo hippy

[Harry Goodwin]

thanks are you using your chuck at that speed. Harry

[Reed Gray]

It has been a while, but I think chucks come with a 'max speed limit' in their literature. I think most of us exceed those limits. I have seen old timers just drive a piece of stock into the morris taper as well.

robo hippy

[Marty Tippin]

It has been a while, but I think chucks come with a 'max speed limit' in their literature. I think most of us exceed those limits. I

Out of curiosity, I looked up the limits in the Nova G3 manual. For "spigot" operations with jaws, you're never supposed to exceed 850 RPM. If you're holding a small piece in the jaw slides (with jaws removed) you can go up to 1800 RPM. Those don't really seem like realistic limits to me, but more likely something dictated by the liability lawyers... But then again, I'm not an engineer so what do I know...

[Michael Mills]

I'm not sure what Nova suggest for speeds with their chucks but here is a chart by them (Teknatool) for various work sizes.
I never thought about not using a chuck at higher speeds, I do but that doesn't mean a person should should. It's odd they would give 1030 rpm for a 10" piece if the chuck was not suppose to be used to hold it.

[Thom Sturgill]

When I took a course at John Campbell on Christmas ornaments a few years ago, the instructor had us turn the speed all the way up on the Powermatics. I just re-ground a spindle gouge based on Cindy Drozda's video and turned an ebony finial (her design) with the re-ground gouge and another with my regular detail gouge for comparison. Thanks to the ornaments course I turned at max on my 1642. BTW, I found the standard fingernail grind at 35 degrees worked better for me. Now I need to turn something to use the two finials on....

The late Dale Nish used a rule that the RPM x Diameter (in inches) = 6000 to 9000 this was mostly concerning bowls:
or RPM = 6000->9000 / diameter.
So a 6" bowl can be turned safely between 1000-1500 rpm by this rule, a 9" bowl at a maximum of 1000 rpm, a 12" bowl 500-750rpm and so forth.

It breaks down on spindles because lathes just don't turn as fast as that formula would allow:
A 1" spindle could be turned between 6000 and 9000 rpm if you could get the lathe up to that speed
a 2" spindle still could still be turned at speeds better than 3000 which is about as fast as any wood lathe will go.

As to the limitations of the chuck - it is more the jaws that create the limit. Standard jaws are rated only up to 1050rpm in compression, 640 rpm in expansion while the 25mm, 35mm, and pen jaws are all rated at 1440 rpm in compression which is the highest nova rates any jaws.

[Harry Goodwin]

Thanks for your help. Harry

[Russell Neyman]

Hackler is spot on. Surface speed is what you need to keep track of, not rpm