Friction drive with some bite?

[Sam Fleisher]

Anybody ever made a jam/friction chuck with some kind of points sticking out to stick into the wood so a bowl won't slip when truing up the outside?

I tighten the tailstock down hard but inevitably when I get to the outside diameter when truing up a bowl it will slip on the jam chuck. Then I get a vibration and have to start over. I figure a lot of it is due to the wax on the inside. These are 12-14 inch bowls so far it's happened to. I used to just jam the bowl on top of the chuck jaws since the inside is going to be re-turned when the bowl is flipped around. Spun pretty easy on the jaws so I tried chucking a piece of 2x4 for a little more friction but that didn't work well either.

Now I'm thinking 4 maybe 6 screws from the back side of my 2x4 block sticking out the front of it so the points would stick in the bowl a little bit and keep it from spinning. I have an axminster multi purpose screw chuck insert accessory but it only has 3 points and isn't a very big circle.

I suppose sand paper would work too or would it just clog up and spin?

Am I the only one this happens to?

 

[Brian Gustin]

Are you the only one it happens to? Nope, not by a LONG shot.

Your screw idea may work for getting a tenon trued up for second turning, but wouldn't be suitable for something like turning off a tenon, nor would sandpaper.

I think you should take it as an opportunity to practice with friction chucks and jam chucks and learn how to take tiny , very light nibbles (especially since while truing up, you're going to be cutting air about half the time) Took me lots of practice and now I also use each true-up of a tenon as an opportunity to practice those cuts before starting into finish turning (and the final turning off the tenon) - It also has led me down the path of being more careful about planning out my bowl shapes, feet, and tenons so I can plan ahead on how the bowl will be held in the chuck after it has dried and warped - This affects the final design and shape of the bowl, but I find that it works out very nicely too. With practice, you may find, like me, that you can take some really delicate cuts when the bowl is just SNUGGED against the friction drive (For finish turning, I get cheap jar opener gripper pads they are soft, white, and if they DO slip they don't leave too much of a blemish that can't be hand sanded or buffed away) without cranking down on tail stock - That is, tighten your tailstock down just enough that trying to turn the bowl against the friction drive, you're able to turn the lathe itself.... Then just learn yourself how to take light cuts (and resharpen your tools if they start to be catchy) until you can true up a tenon without the bowl spinning on the friction drive.

 

[GRJensen]

Not sure if this is what you are looking for ... I use this when I am roughing out bowls. The 4 pointed bolts can be adjusted to get a firm hold on an uneven bowl blank. This one is 8" in diameter. The back side has a dovetail recess that fits Nova 50mm jaws.

 

[Gary Beasley]

This is a jig designed by Glenn Lucas for handling this situation. The high points of the warped rim goes into the open sections and you can adjust position as needed.

 

[hockenbery]

Anybody ever made a jam/friction chuck with some kind of points sticking out to stick into the wood so a bowl won't slip when truing up the outside?

I get good results using a 4 jaws scroll chuck with the jaws open with a space of 1/4 inch or so.
If the bowl rocks a bit I open or close the jaws for improvement. The corners of the jaws bite into the wood a bit bowls don’t slip.

I also line up the rims so I can get the largest bowl shifting on the jaws before final tightening.

As a bonus the chuck is already there for mounting the bowl to hollow.

 

[Norm Marentette]

Built one like Gary, got the idea from Glen Lucas also, works like a charm, use it a lot.

 

[Kevin Jesequel]

It would probably work. You could buy or make something like the Elio drives that Tod Raines sells over at Woodturningtoolstore.com. I use @hockenbery ’s suggestion of a chuck with the jaws opened a little. I’ve never had a problem with the bowl slipping, but I also prefer to finish as much of the bowl as possible in the chuck, so I only true up the tenon plus about two inches before flipping it into the chuck to finish the rest.

 

[Doug Freeman]

Sometimes I use chuck/jaws, or one of the friction chucks I made for tenon removal on finished bowls (various dia from ~2” to 6”). With the frictionchuckes I use a ~1/16” thick piece of leather. I true the tenon and a small part of the lower OD. I prefer to finish turn the OD in the chuck - too many that did not turn true when I flipped them caused me to only finish the OD in the chuck. Once flipped I get the OD and ID almost round, then finish the OD then the ID. Stress relief when removing the ID warp can cause the OD to go out of round.

 

[Sam Fleisher]

It would probably work. You could buy or make something like the Elio drives that Tod Raines sells over at Woodturningtoolstore.com. I use @hockenbery ’s suggestion of a chuck with the jaws opened a little. I’ve never had a problem with the bowl slipping, but I also prefer to finish as much of the bowl as possible in the chuck, so I only true up the tenon plus about two inches before flipping it into the chuck to finish the rest.

Elio drive, that's what I couldn't think of. I have the axminster version of that but I figured it was too small for the way I do it.

I probably need to change to the way that was said in your post and just true the tenon instead of trying to do the complete outside before flipping and putting in the chuck.

I'll need to relearn some technique or work on my left handed turning because it's awkward for me.

 

[Don Wattenhofer]

Examples of sandpaper friction chuck to make bottoms for coopered/stave containers or shrink boxes without any center markings. The first pic is making the bottom for a 15 stave tankard and the second is holding a button blank to do the outside contour.

 

[hockenbery]

probably need to change to the way that was said in your post and just true the tenon instead of trying to do the complete outside before flipping and putting in the chuck.

There are many ways that work. Advantages to them all.

On finish turning twice turned bowls
I generally turn the whole outside of a returned bowl on the friction drive. No sanding.
If it doesn’t run true in the chuck I’ll take a light pass or two to true it up and shear scrape it.

On once tuned bowls between centers I turn the outside shape up to the finish cut.
I do the outside finish cut after it is in the chuck and after I have done some hollowing to release tension if it is there.

 

[Owen Lowe]

I get good results using a 4 jaws scroll chuck with the jaws open with a space of 1/4 inch or so.
If the bowl rocks a bit I open or close the jaws for improvement. The corners of the jaws bite into the wood a bit bowls don’t slip.

I also line up the rims so I can get the largest bowl shifting on the jaws before final tightening.

As a bonus the chuck is already there for mounting the bowl to hollow.

...I use @hockenbery ’s suggestion of a chuck with the jaws opened a little. I’ve never had a problem with the bowl slipping, but I also prefer to finish as much of the bowl as possible in the chuck, so I only true up the tenon plus about two inches before flipping it into the chuck to finish the rest.

I'm really only interested in re-truing the tenon and its face to remount in the chuck. I purposefully leave a tail center mark when roughing out the green blank which I use as my tenon center when friction re-truing the dried rough out.

 

[Dean Center]

Anybody ever made a jam/friction chuck with some kind of points sticking out to stick into the wood so a bowl won't slip when truing up the outside?

I tighten the tailstock down hard but inevitably when I get to the outside diameter when truing up a bowl it will slip on the jam chuck. Then I get a vibration and have to start over. I figure a lot of it is due to the wax on the inside. These are 12-14 inch bowls so far it's happened to. I used to just jam the bowl on top of the chuck jaws since the inside is going to be re-turned when the bowl is flipped around. Spun pretty easy on the jaws so I tried chucking a piece of 2x4 for a little more friction but that didn't work well either.

Now I'm thinking 4 maybe 6 screws from the back side of my 2x4 block sticking out the front of it so the points would stick in the bowl a little bit and keep it from spinning. I have an axminster multi purpose screw chuck insert accessory but it only has 3 points and isn't a very big circle.

I suppose sand paper would work too or would it just clog up and spin?

Am I the only one this happens to?

Glenn Lucas has advocated for a drive much like what you ask about. Gary shows his returning friction drive and that's not what I'm suggesting. Glenn's drive is something like a faceplate, with a post in the center and 4 (or more if you like) sharpened bolts attached. I couldn't find a picture, but at about 55 seconds, you can briefly see it here in this abbreviated bowl turning video. I'm sure it would be more obvious in Glenn's actual DVD.

View: https://www.youtube.com/watch?v=vqzdaiXJk24

 

[Sam Fleisher]

Glenn Lucas has advocated for a drive much like what you ask about. Gary shows his returning friction drive and that's not what I'm suggesting. Glenn's drive is something like a faceplate, with a post in the center and 4 (or more if you like) sharpened bolts attached. I couldn't find a picture, but at about 55 seconds, you can briefly see it here in this abbreviated bowl turning video. I'm sure it would be more obvious in Glenn's actual DVD.

View: https://www.youtube.com/watch?v=vqzdaiXJk24

That's like an extra large elio drive isn't it?
That would work if I took the center screw out maybe. I need something for once turned bowls that I'm finish turning.

 

[Don Wattenhofer]

I tighten the tailstock down hard but inevitably when I get to the outside diameter when truing up a bowl it will slip on the jam chuck.

I need something for once turned bowls that I'm finish turning.

The method I use on once turned bowls is to first mount the blank with a wood worm screw then turn the tenon and the outside to final form before I turn it around to do the inside. The final step is to turn off the tenon only and shape the foot which of course is a smaller diameter that does not take a lot of force to prevent slippage.

 

[Sam Fleisher]

The method I use on once turned bowls is to first mount the blank with a wood worm screw then turn the tenon and the outside to final form before I turn it around to do the inside. The final step is to turn off the tenon only and shape the foot which of course is a smaller diameter that does not take a lot of force to prevent slippage.

I'm sorry, I stated that wrong. Once turned to me is a bowl that has been roughed out, dried and I'm re-mounting on the lathe to finish turn or "second" turn before applying a finish.

 

[Dean Center]

I'm sorry, I stated that wrong. Once turned to me is a bowl that has been roughed out, dried and I'm re-mounting on the lathe to finish turn or "second" turn before applying a finish.

If that's what you're doing Gary's Glenn Lucas friction chuck is an option, and there are rim friction chucks, and jam chucks of wood or even just the jaws of your chuck. I can't think of anything I've seen that has points for returning bowls. It would inherently cause a little damage. All you really need is something to hold it briefly while you gently true up the tenon or mortise.

 

[Sam Fleisher]

If that's what you're doing Gary's Glenn Lucas friction chuck is an option, and there are rim friction chucks, and jam chucks of wood or even just the jaws of your chuck. I can't think of anything I've seen that has points for returning bowls. It would inherently cause a little damage. All you really need is something to hold it briefly while you gently true up the tenon or mortise.

Like I said in my first post, I have been truing up the whole outside before flipping to finish turn the inside. That's when it was slipping on the chuck jaws, block of wood I chucked up and a regular jam chuck. It seemed to work better for me that way on 6-8 inch bowls because can't get around the headstock as easy when starting with tenon in chuck. On a bigger bowl I guess I just need to change my process and do inside and outside without changing the orientation of the bowl on the lathe.

 

[Dave Landers]

Like I said in my first post, I have been truing up the whole outside before flipping to finish turn the inside

That/s what I usually do, too. Finish turn and sand the outside - between centers. I do fix up the tenon first, so it's true, just in case. I don't have a slippage problem.

Sometimes I mount the bowl on the chuck jaws, but usually it's more convenient to use a friction drive - a scrap block of wood in the chuck. Turn the scrap round, no sharp corners. If the bowl you're turning is slippery inside for some reason (wax?) you might want to get rid of that. Add something (drawer liner or that stuff to keep rugs in place) to increase the grip. If the bowl is more out of round, an old mouse pad will add cushion that helps the drive block conform to the surface.

A larger and severely out-of-round bowl does benefit from the Glen Lucas-style drive plate. You can't get all the way to the rim of the bowl (without hitting the plate), but you can get close and deal with it when it's turned around on the tenon - either fix up that bit or cut it off.

 

[Steve Chaplin]

For re-truing the tenon I just put a 5-6" foam buffing pad (used to buff out cars) over the chuck with the jaws opened up an appropriate amount for the bowl diameter works well. I have also seen turners use rubber drawer liner like this stuff.
I like the foam buffing pad better as I also use it to jam chuck finished bowls and it protects the interior better. It has a tough hook and loop backing that goes against the chuck which keeps it from ripping.

 

[Mike Harman]

Instead of using pins as per one photo I use hot glue.
I have been using the hot glue method for about twenty years and have never had any problem with it not holing the object that I am turning After I finish the piece I simply use a hot air gun to release the object from the friction plate te cold glue i easily removed with a sharp chisel and leaves no marks. Hope that this helps.

 

[Sam Fleisher]

Instead of using pins as per one photo I use hot glue.
I have been using the hot glue method for about twenty years and have never had any problem with it not holing the object that I am turning After I finish the piece I simply use a hot air gun to release the object from the friction plate te cold glue i easily removed with a sharp chisel and leaves no marks. Hope that this helps.

That's a good idea, but the ones I'm having trouble with have been turned once and have anchor seal on them. Glue probably won't stick will it?

 

[Dean Center]

the ones I'm having trouble with have been turned once and have anchor seal on them.

Sam, you don't have to apply the anchorseal to the inside of the rough turned blank. Many of us only apply outside, and a few only apply to the end grain outside.

 

[Sam Fleisher]

Sam, you don't have to apply the anchorseal to the inside of the rough turned blank. Many of us only apply outside, and a few only apply to the end grain outside.

I didn't, it was on some rough bowls I acquired.

 

[Mike Harman]

Hi Sam Giv the glue a go you may be surprised if it wont stick you will know straight away and it is easy to remove.
The other way I do it is to use a forstner bit and bore a very shallow hole on the base then i fasten a piece of scrap ply or wood to a small face plate turn this down to the size of the plate with a spigot the sie of the hole bored. mount the piece and bring up the tail stock to hold it using a very small piece to stop the point damaging the work when you finish if you dont want the hole turn a plug to fill it and glue in sand and walla all done I have just finished a cake stand using this method keep the plugs etc you make to reuse. good luck
Mik

 

[Leo Van Der Loo]

This is my way of holding pieces, even not flat or round, held on the outside or inside, and without damage.

These are held securely even when not flat or round, wedges to keep them from rocking and sliding buttons to hold them centred.
These are old preturned bowls I turned, that are returned to be finish turned and held in a chuck.





solid hold without any damage and nothing to obstruct from turning .