Looking for Ideas

Re: Looking for Ideas

Mike Schwing from Maryland

>Without seeing it, you could turn a disc to fit snug just inside of the rim, and wrap the entire thing tightly with stretch plastic wrap. I'd mount the disc on the spindle, position the bowl as true as possible, and start wrapping that thing with plastic stretch wrap. The only problem I see is getting the bowl centered well with no tailstock. But you can achieve a hold on that sucker that will not come loose, definitely.

Re: Looking for Ideas

Brad Homman

>You could easily make a jig like Bill Grumbine did, he gives instruction at: http://www.enter.net/~ultradad/bowljig.html

Re: Looking for Ideas

Ben Aragon

>Steve,

A long term fix would be to build a vacuum chuck and use a 6" or 8" piece of PVC pipe and a rubber casket and vacuum chuck to the inside of the bowl. This would be an excuse to build a vacuum chuck system and you would have it forever. I use mine all the time for just what you are trying to do. With 15 lbs. of pressure per square inch, on a 6" diameter that would be over 400 lbs of holding power. Normally the vacuum adapter would be a sealed bearing mounted in a wood or aluminum plate mounted on your outboard hand wheel and then a hose fitting pressed into the inner race of the bearing. You can make vacuum plates from plywood with rubber face to mount bowl at the rim. Or use PVC tubes and rubber gaskets to mount to the inside of the bowl. Both of them are built on faceplates and trued. Surplus vacuum pumps can be found on Ebay pretty cheap. I used brass-plumbing ball valves for around $4. A 0-30� Hg vacuum gauge will be need also, just saw a nice one sell on Ebay for $9. I built mine for around $100 or less. I use it to remove the foot of a bowl and decorate the foot.

Ben

PS: Sorry, I know this is not a lot of help.

I remember seeing you do this

steve antonucci

>I doubt that you used Glad Wrap. Did you get the industrial stuff at HD? How much did you use?

I've seen it in 3' rolls, does it come smaller?

Steve

P.S. Without seeing it, you've got the right image :-)

Thought about this too...

steve antonucci

>I didn't have any plywood (that big) laying around. Looks to be a great solution, might have to try it.

Steve

Re: Looking for Ideas

Ron in Drums PA

>I've never done this, I'm just thinking out loud.

Can you glue two pieces of MDF together, mount them to a faceplate. Then turn a jam chuck, and use plastic stretch wrap to aid in securing everything together.

Yes, plastic stretch wrap does come in 4" and 2" widths. For a roll at a time check with a place that rents U-Haul trucks and trailers.

Hand carve it off

Joel Hunnicutt

>a couple of times for various reasons I have had pieces that I couldn't reverse chuck. In those cases I grabbed a couple of carving gouges and dished out the base. I really think it looks ok to have the pattern carving tools make in the foot of the bowl. It really looks hand made.

Make bigger jaws

Dominic Greco in Richboro PA

>Steve,

Mark Kauder has an article here on WC that details how to make cole jaws for your chuck. Why not take that one step further and make larger cole jaws that will have the capacity to hold this bowl?

Another solution is to build a Longworth Chuck. These chucks are very useful for holding large platters or bowls securely by the rim. If I hadn't made a vacuum chuck, I would have opted to make one of these.

See ya around,

Dominic

Re: I remember seeing you do this

John Lucas

>Steve

try the office supply stores. They have it in 6" rolls. It's great stuff for this. I always used Blue painters masking tape. It comes off easily and if it leaves any residue it comes off easily. If I'm concerned about the bowl coming loose I back up this tape with nylon filament tape. That stuff won't break but doesn't always stick to the blue stuff that well.

Re: Looking for Ideas

Bill Hale

>Steve

Buy a piece of plywood mount it to a face plate and turn it round. True up the face if needed.

Make it larger than you need this time and cut a light jamb chuck groove to fit your piece.

Set the bowl in to the groove and use shrink wrap to hold it tight.

This is quick, easy and cheap. It also allows you to reuse the plywood for future work, smaller or larger. Just mark which face plate was used and mark each so you know the screw patern.

Good turning and be safe

Bill

Re: Looking for Ideas

Doug Leite

>Steve,

What I have done in the few times that my vacuum chuck wouldn't hold is to mount a plywood disc at least 2 1/2"-3" larger than the piece on a faceplate. After truing the face and OD, I enscribe 2 circles with a pencil, first the dia. of the piece, and second about 1/2" away, or 1" larger. If you are familiar with machinist "step clamps" as are used on a mill, I make something that works similar. Sometimes, I cut 4-8 pieces of 1 X 2 X 3" long, drill a hole for some kind of a screw about 1" from one end and spacers the same thickness as the rim. With the faceplate off of the lathe and on a workbench, I line up the piece in the first circle and clamp it to the faceplate with these "step clamps" with the screws going in on the outer circle. Works every time, and I have held some pieces about 30" dia using as many as 12 clamps.

Re: Looking for Ideas

Doug Leite

>Steve,

Another Idea entered my foggy mind after thr last post. My old time friend and founder of our club, Mr. Jack Straka, is featured in a book "Master Woodturners" by Dale Nish. If you can lay your hands on a copy, on pages 180-184, he shows his method of using a large faceplate and wooden rings connected by threaded rods to hold work to finish the bottoms.

Aloha

Doug

Thanks all: What I did...

steve antonucci

>Here is an on-hand solution, based upon the notion that you can fix anything with Duck Tape.

I turned a plywood disk which I trued to a small "jam chuck". The recess was about 1/8", and the bowl might have wiggled ~1/32" (not perfect, but 1/64" over 17" doesn't bug me!)

Then I just duct taped the bowl to the disk. I pulled the tape tight, and it not only held, but allowed me to turn the lathe up to 400RPM!

Front side:

Backside

steve antonucci

>As you can see, it wasn't pretty, but it worked like a charm.

Thanks for all the ideas.

Steve

Finished

steve antonucci

>Yeah, I know, there's still screw staining there... I'll bleach it out and fill the hole .

Steve

Re: Finished

Arch

>Hi Steve. Looks like you are going to have a very nice bowl bottom. Internal jam chucks work so well on open bowls that your query makes me wonder about devising an adjustable tail center that can follow my N3K's swivelling headstock. Maybe put a dead center on a long toolrest to share with the tool? As usual, my sugestions bring up the rear. This time the tailstock! :) Arch

Mebbe next time . .

Al Kapocius, Metro Greendale

>Once saw a suggestion to use a router to face off bowl bottoms. Mebbe make a platform or template to fit over the bottom as a base surface.

Al Kapocius

Check Bill Grumbines web site

John Cotten

>He has a great set of plans for making a bottom finishing jig.

I made one a couple of years ago, and it works great.