what speed are you turnng?

[Terry Achey]

Here's a question I've been meaning to ask for awhile. I've only turned several bowls to completion, so I don't have alot of hands-on experience in terms of understanding what speeds work best for the different situations and steps. My bowls are ususally range from 6" to 11" with woods such as cherry, oak, walnut. I use a Jet 1236 so I believe the speed is limited to about 1,700rpm. I've experimented a little with differing speeds but thought I would seek advice for the seasoned Sawmill vets ;)

- roughing out speed?
- finish turn speeds?
- sanding speeds?
- misc steps & speeds?

I suppose this is rather a broad topic, but thought I'd cast the wide net and see what I can learn. Thanks in advance for sharing!

Terry

[Allen Neighbors]

roughing out speed? This depends on the blank. If it's pretty rough and out of balance, I'll start out as slow as possible to keep vibration of the lathe down... sometimes as low as 250 or so, up to about 1000.

- finish turn speeds? To make finishing cuts, I turn the speed up high as I dare, and take light cuts... usually about 1500 to 1800 rpm. I always use a bowl steady when I'm turning the interior of bowls. Even thick ones.

- sanding speeds? Sometimes faster for rougher grits... but normally less than 1000. When I get down to 220 or smoother, I slow to about 4-600 rpm. Wet sanding about 400 rpm.

- misc steps & speeds? When turning away tearout, I'll turn up the speed until I think it's getting a little unsafe, and then slow it down just a bit and take lighter cuts. :)

[Judy Kingery]

Hi Terry,

Interesting query and I'll look forward to what others say. In general, on my Dad's old lathe, we never knew what speed we were turning, manual changes on a multi-size pulley, so I'd just guesstimate now, between 800 and say 1,700 rpms tops.

A couple suggestions - pay attention to sound. That, to me is critical, balance, how it looks and sound, when it's running sweet or optimally, you can tell by listening, watching and of course vibration or the lack thereof, for what you're doing.

Having said that, our new lathe has a guage on it so you know exactly how fast or slow you're turning, if you want to know. I seldom pay attention, but sometimes glance, just to see.

-asymetrical pieces - s-l-o-w, anywhere from maybe 75 rpms to 125 or so
-roughing an unbalanced blank or just cornered blank - about 300-500
-roughing a blank pretty rounded prior to mounting on lathe - 700-800
-bowl gouge on a trued up blank - easily 1,400-2,000
-sanding speeds - depends on what I'm doing, varies 500-1,000
-polishing - if I'm buffing probably I'd guess 1,700
-polishing - friction polish, I run it up fairly high, again a guess, 2,000+
-misc - wire burns, again high for a quick and clean burn, 2,000+

Anyway, this is just what works for me and - do take these figures with a slight grain of salt as I seldom note the specific rpms and turn like I did as a kid with the look, listen, and feel and you can pretty much gauge your optimum by carefully sorta playing with it, adjusting it just as you've been doing.

Best to you, hope this helps or at least maybe other folks will jump in with better information for you!

Jude

[Richard Madison]

Terry,
Am sure your replies will indicate very different strokes for different folks. In general, the speed increases with the experience of the turner, and of course increases as the size of the work decreases. No doubt professional turners work much faster than many of us. I'm probably slower than most, but the following would be for your range of 6" to 12".

roughing a chunk until nearly round and balanced ---200
rough turning a round, balanced piece ---400 to 600 depending on size
finish cuts ---600 to 850 faster speed + lighter cuts = smoother
power sanding ---100 or less
hand sanding ---600 to 800

If there is much vibration, that's too fast, and if you are not comfortable at (whatever) that speed, it is too fast. Pay no attention to, and do not attempt to emulate the guys who claim to turn at 10,000 rpm and begin sanding at 600 grit. Just do what is comfortable for you and seems to work ok.

[Dennis Peacock]

I go from really slow (slow enough to count the gouge ticks as the wood passes by with lots of "air" between them) all the way up to about 1800 RPM. I've been guilty of running a lathe faster than I really needed to. But hey, I like it that way at times. :D

[Steve Schlumpf]

For roughing out (from chainsaw straight to the lathe) I usually am running around 250 rpm until the blank gets a little more balanced. I increase the speed a little at a time by turning the speed up until the lathe starts to vibrate and then turn it back down until the vibration just stops. Usually max the speed out somewhere around 800 to 1000 rpm depending on the size of the blank.

Finish turn around 800 to 1000. Sanding by hand is around 300, power sanding around 150.

[Jim Becker]

Rough turning a very rough and unbalanced hunk of wood...probably 50-100 rpm tops. General turning from there starting at about 300-400 rpm and never more than 1200 rpm for bowls and vessels. Higher RPMs are available if I switch the belt range, but I don't do much spindle work and even then, the 1200-1400 top speed on low range is more than satisfying to me. For power sanding, I drop back down to a few hundred RPM to keep frictional heat down a little.

[Jim Underwood]

Phil Colson put it succinctly and best:

"Threshold of Fear"

:eek::D

[Reed Gray]

Speeds are whatever you feel comfortable with. Do work your way up to higher speeds, don't just crank it up and plunge in. The RPM is just as important as the FPM (feet per minute). A 16 inch bowl fpm speed is very fast at 1500, on the rim, but much slower on a 1 inch spindle.

The blessing of variable speed is that with bowl blanks, you can start as slow as you want, turn it up till it starts to vibrate, then back it off a bit. If you are turning while the lathe is shaking, the shaking will result in a bowl that isn't round. Chainsawn blanks are never balanced, and even of you totally prepare your blank on a bandsaw, they are seldom balanced, so there will be some vibration. Some pieces never balance, just because.

I have 3 speed ranges on my lathe, low for big out of balance pieces (up to about 500 rpm), medium for most other pieces (up to about 1800), and high for spindles (almost 3000). I have no trouble starting with a 10 inch bowl at 1800 rpm. My lathe can handle that. I will turn as fast as the lathe can handle without vibrating. When it is balanced out, I turn the speed up. Cutting is much easier for me at higher speeds, especially the finish shear cuts. Turning smaller bowls in the 5 inch and down range seems slow at 1800, and I can see turning them at 3000, but I don't want to change the belt. I do wish there was a gear shift for lathes to make speed ranges easier to change. If there is bark on the piece, I will turn slower until almost all the bark is off. I have had pieces fly off. If there are any cracks in the wood, I turn slower, and/or stabilize the piece by filling it with super glue and dust. I will first hit it with the thin glue, then with the thicker glue, and wait for it to seep all the way in and cure before turning. I don't use the accelerators because the glue will cure on the outside, and not on the inside (super glue on glasses, cloths, and face shields isn't fun). I don't want pieces of wood flying off at 200 rpm any more than I want them flying off at 1800. It doesn't take a catch for a piece of wood that is cracked to come flying off at you. Even if I have glued a crack up, I will turn slower. Again, start slow and work your way up, as long as you are comfortable.

For sanding, I turn the lathe as slow as possible. I turn green to final thickness, then let them dry and warp. I had the minimum slow speed on my lathe set down from 50 rpm to zero. 50 rpm is too fast for a warped bowl. I can manage most of them at 10 rpm, but some I have to hand turn. I power sand, and have a piece of cork under the trigger to keep my speed down. High sander speeds, and high wood speeds generate heat which can cause cracks and checking in the wood, and your paper wears out faster. Slower speeds also do a better job of sanding, and it doesn't take any more time.

robo hippy

[curtis rosche]

you can really turn what ever speed you want, but what these guys have said is what works best. remember though, the faster you go the more force is trying to pull the wood outward, like on the spinny rides at a carnival, so if you have something really thin and go really fast, boom! there goes your peice. i have found that if you are going to fast when roughing that you will need to sharepen the tool more and that it doesn take off wood as quick. do what you feel comfortable with, start with a scrap peice and play with different tools and speeds, you will learn what you like best

[Paul Engle]

Well lots of replys for sure, I turn dead slow during roughing and full tilt boogie the rest of the time and slow to 2000 rpm for sanding, brown paper bag polishing, and 20 rpm to apply Tung Oil ( formbys) and burnish , and about the same for wipe on poly ( I use a piece of foam to apply ) and let turn dead slow for 20 - 30 minutes then take off.

[Jim Becker]

Paul, you have to be somewhat careful with top speed as the size of your piece increases. Even a moderately sized bowl could be dangerous spinning at 2000 RPM if there is any hidden defects. And remember the rim speed of the workpiece is moving much faster at a given RPM you are "dialing in" on the lathe as the size increases.

[Terry Achey]

Thank you all for the remarks. Looks like personal preference dicatates speed for many folks, along with a common theme for low speed turnings for rough, out of balanced pieces.

I've been roughing out slow speed and gradually increasing my speeds on finishes. I found faster speeds especially helpful while trying to shear some tangent cuts as instructed by Bill Grumbine. I must admit that some new techniques and speeds were scary:eek: I've been doing alot of fine sanding at mid-speed, too. Probably around 900 to 1,200rpm. I thought it did a better and faster job at this spped. Now, I'm going to have to go back and try some slower speeds for sanding and do another comparison.

Anyway, I appreciated all of your comments. Thanks and have a favorable weekend!

Terry