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View Full Version : Slow Speed Sanding and Reducing Lathe Speed



Dale Winburn
07-19-2013, 9:55 AM
This post is in response to Reed Gray Slow Speed Sanding (http://www.sawmillcreek.org/showthread.php?205594-Slow-Speed-Sanding&p=2132851#post2132851) and Eric Gourieux Reducing my lathe speed (http://www.sawmillcreek.org/showthread.php?205626-Reducing-my-lathe-speed&p=2133181#post2133181).

Occasionally I turn natural edge bowls green to final thickness and then leave them to dry for one to two weeks before final sanding and finishing. Some times these bowls warp considerably making it impossible to sand with the lathe running.

As I was sanding these bowls, on the lathe but not running, I would have to stop sanding and rotate the bowl every few seconds. I thought what if I could turn the bowl at a very slow RPM I could continue to sand as the bowl turned.

I had an old gear motor I picked up somewhere, maybe at a garage sale. The output shaft turned at 30 RPM so I mounted the motor on a piece of plywood and connected it to my bowl lathe through the existing four step pulley system, I’m using the lathe motor as a jack-shaft. With this set-up the bowl turns at approx four RPM, this lets me continue to sand as the bowl turns. It’s also very easy to follow the natural edge of the bowl even with warping caused by the drying. I’ve tried this on a couple of bowls so far and it works very well.

Let me know what you think.

Dale

Scott Lux
07-19-2013, 10:33 AM
Genius!!
I now know how to keep finish from sagging

Dale Winburn
07-19-2013, 11:03 AM
Genius!!
I now know how to keep finish from sagging

That a great idea, I never thought about putting on the finish, especially a spray finish, with the bowl turning.

Mike Cruz
07-19-2013, 12:15 PM
Finish won't sag at 1000 rpm either! :D

Great idea, Dale. Great execution as well.

robert baccus
07-19-2013, 11:37 PM
Dale, your sanding thing works well. My 3520 rpm goes down to zero and I've sanded like that for years. It also works for rough cutting with a scraper at 20-30 rpm but you must hold the tool gingerly& lightly to follow the in and out thing.

Eric Gourieux
07-20-2013, 12:21 AM
Dale, that's a great idea. What kind of lathe is that?

Dale Winburn
07-20-2013, 8:53 AM
Eric, The lathe is my home built bowl lathe.

http://www.sawmillcreek.org/showthread.php?138559-Home-made-bowl-lathe&p=1404931#post1404931

Scott Lux
07-20-2013, 2:18 PM
Well, I just bid on a rotisserie motor on eBay. I figure 60 rpm, and plenty of torque for a lathe with the belt loosened.

Roger Chandler
07-20-2013, 5:16 PM
That is a slick setup Dale! Of course, you always seem to be able to find a solution to a lot of turning issues..........nice job on this.........lots to think about for a future setup, perhaps..........thanks!

Scott Lux
07-20-2013, 11:10 PM
Finish won't sag at 1000 rpm, but you can make a "porcupine" pen with CA finish at that speed.

Mike Cruz
07-21-2013, 9:14 AM
I suppose that would still be sagging...not along a line, but an instant sag radiating outward from the pen! That might actually look pretty cool, Scott. ;) May not be comfortable to write with, but would look cool. :cool: