Returning a recessed bowl?

[Matt Newton]

I have roughed and returned hundreds of bowls but have always done this using a tenon to chuck the bowl. I recently was given a rough turned walnut bowl that was done with a recess. How do you true up the recess to finish turn the piece? I am stumped :)

[Richard Dooling]

Can you jam chuck it with the tailstock in place for support since you don't need to get all the way to the center?

[John K Jordan]

I have on occasion carved the oval into a circle with hand tools.
I have also mounted a bowl that wasn't too large in Cole jaws and turned the recess round.
I can imagine using a router with a little circle template in some cases.
And as mentioned, jamming the bowl between a stick in a chuck (or something like a rubber chucky) and the tailstock and turning the recess will often work.
Vacuum chuck might work if you can get a good seal on the inside.

JKJ

[Sonny Kemp]

Can you jam chuck it with the tailstock in place for support since you don't need to get all the way to the center?

x2 That's how I do it too.

[Matt Newton]

Can you jam chuck it with the tailstock in place for support since you don't need to get all the way to the center?

My thought was that I couldn't get a good dovetail with the tail stock in the way. I'll give it a try and see though.

[Sonny Kemp]

It can be difficult Matt.I posted that exact question a little while back and got several good fixes for the tailstock being in the way.You can search for my post and get it.

[John Grace]

Is the bottom thick enough to accept a face plate with short screws? Turned slowly, that would give you clear access to the bottom to true of the recess or you may try a glue block.

[John K Jordan]

Is the bottom thick enough to accept a face plate with short screws? Turned slowly, that would give you clear access to the bottom to true of the recess or you may try a glue block.

I didn't even think about a glue block. I assume you meant finish turn the piece with a glue block on the bottom but he could fit one inside just to true the bottom and recess, then turn away the block.

[Leo Van Der Loo]

One of my ways, as I use a recess almost exclusively.

http://www.sawmillcreek.org/showthread.php?246777-Jumbo-jaws-Vicmarc-or-Stronghold&highlight=Jumbo

[Reed Gray]

Most of my warped bowls have moved too much to be able to use the cole jaws like Leo shows. You might get 4 of the feet to engage, but not the other 4, so it wouldn't be very secure. When I sand the warped bowls, I can wiggle the bowl around when expanding the chuck, most of the time, and get a hold that is good for sanding (all 4 chuck jaws in contact), but I wouldn't try to turn with that hold. My recess is generally 1/8 inch or less deep. If you have one that is 1/4 inch deep, you may be able to do it, but I would keep speeds way down. I know there are attachments for mounting your chuck in the tailstock, but then you could only turn a tenon. If you have a vacuum chuck, you may be able to center it close enough to return the recess, then reverse. Glue block would work if you have a flat bottom, but again the warping would cause problems. This one has me stumped....

robo hippy

[John K Jordan]

Most of my warped bowls have moved too much to be able to use the cole jaws like Leo shows. You might get 4 of the feet to engage, but not the other 4, so it wouldn't be very secure. ...

You can make some buttons different sizes for the cole jaws. But if the warped bowl rim will catch on four buttons I would consider support by pressing on the middle of the base with the tailstock to clean up the recess.

To avoid pushing a point into the wood I use a live center with a flat tip.

I have also pressed with a piece of turned wood on the live center, flat on the end. I use a 3/4"-10 tap to make threads in a block to thread onto the oneway style center, then put the center in the headstock and lock it with a piece of soft wire to turn the wood to what ever shape needed. I made a bunch of these to make various tailstock jam supports. The nice thing about using wood here is I can cut into it if necessary (or by accident.)

If tool clearance is an issue grind the end of a small scraper to clean up the dovetailed recess.

But I think just hand carving the recess into a circle would be quicker for just one - draw a circle with a compass and even use a Dremel to round the oval so the chuck will grip securely.

JKJ

[Richard Dooling]

It might help to see the bowl with a something to use as a frame of reference for size.

John makes a good point about using a flat or reverse cone live center to spread out the pressure. Probably lowest speed that still cuts clean unless you're pretty confident in the mounting.

Also would use tail stock quill at near full extension. I was thinking a dovetail shaped scraper like the Nova - it's pretty small.

[Reed Gray]

Hmm, after thinking a bit, and seeing stacked buttons, and remembering a set up some one made that would go up to 4 inches or so high... how about an L shaped button that would support under the rim as well as pushing inward, to keep it from rocking. It would have to be on a screw thread of some sort, and probably fairly sturdy. It would help fine tune the leveling part too since many woods will not warp evenly. Not a high speed turning set up for sure, but....

robo hippy

[Michael Mills]

I usually use a recess and made this about 6-7 years ago (it may be posted on here somewhere). It is presented 45* to the tool rest so you can get in close without hitting the tailstock. A large screwdriver would give enough meat to cut or true up the recess. Someone (maybe Mike Peace?) made a youtube video on how to make the tool last year.
I never remove the center on the initial turning so it is there to realign when dry.

If you have a Nova live center you can also use the "threaded insert" with a bolt 3-4" long to move the tailstock away.

[Leo Van Der Loo]

Hmm, after thinking a bit, and seeing stacked buttons, and remembering a set up some one made that would go up to 4 inches or so high... how about an L shaped button that would support under the rim as well as pushing inward, to keep it from rocking. It would have to be on a screw thread of some sort, and probably fairly sturdy. It would help fine tune the leveling part too since many woods will not warp evenly. Not a high speed turning set up for sure, but....

robo hippy

Reed I have turned a lot of bowls over the years as you know, and not things from dried wood, but each and everyone from fresh green wood,from small to very large, and returned most of them again, but for the turned to finish pieces.

I use different ways to hold them depending the amount of change in the piece, quite often I can hold the bowls oval recess good enough to flatten the top and then mount on the Jumbo jaws and re-turn the recess.
351685

Other times if the warpage isn’t much, I will hold the oval piece on the Jumbo jaws and use some wedges to lift and secure it so it will not wobble while re-turning it.
the hold is often good enough to return the recess and the outside of the piece right up to the buttons while held in the Jumbo jaws.
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By using the slots in the Jumbo jaws I can get most of or all buttons to hold the piece, when holding with just slight pressure and then sliding the other buttons and tightening them down, all the buttons will hold when then tightening the chuck.
351688

If a piece is warped a lot or like with a natural edge bowl, I’ll use a cylindric piece in the chuck with foam between it and the bowl for traction and damage prevention, and the tailstock pressure holding it, there are lots of ways to hold a piece.
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To return the recess while the tailstock is holding the bowl and preventing of easily doing this, I made a tool to do that, shown here a few times before, by grinding this tool as shown you can reach the recess easily.
351691


As I use the standard Oneway jaws I make a straight sided recess, for a dovetail you will need to grind ita bit more an hold it at the right angle, HTH :)

[Greg McClurg]

I ground a small scraper like Leo uses and it works great.

[Leo Van Der Loo]

I ground a small scraper like Leo uses and it works great.

Thanks Greg, yes because of the angle you get well away from the tailstock and are able to return the recess :D

[Brice Rogers]

1. It helps if you left a dimple in the recess in the bottom to align with the tailstock live center.
2. The tailstock can get in the way. Sometimes you can work from the backside of the lathe. But if that doesn't work....
3. I took a chunk of file (high carbon steel), took out the hardness, reshaped it, and rehardened it. I screw it onto the end of a 1/2" square shank and it allows me to position it at about a 45 degree angle and recut the recess. The geometry allow me to recut the recess without the tailstock being an issue. I have also seen a scraper reshaped to do the same thing.
4. For a one time tool, you can make out of any steel. Shape it, sharpen it, and use it. When you're done, it'll be ready for resharpening. But that will take 60 seconds or less...


My thought was that I couldn't get a good dovetail with the tail stock in the way. I'll give it a try and see though.