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turnerted
11th June 2006, 05:18 PM
Hi
This is my first post although I have been a regular reader of the forum for some time . I have just turned my first hollow form . It looks like a flying saucer and I used a Bruce Leadbetter hollowing tool . My queary is what is the best way to mount this to clean up the base ? Obviously I can't use my bowl jaws . I tried gripping it using my long reach jaws through the hole but this was not satisfactory and would have marked the neck . I'm sure there must be an easy solution so I await words of wisdom .

rsser
11th June 2006, 05:37 PM
Bit hard to say without a pic.

Maybe turn a cone that will fit into your aperture, pad with some soft material (paper towel might do, or some flat strips of router mat), bring up your tailstock, putting some packing between the point and the base of your piece. Clean up as much as you can, then finish off by hand.

dazzler
11th June 2006, 05:48 PM
I would use one of these

cheers

dazzler

Skew ChiDAMN!!
11th June 2006, 07:15 PM
No, no, Dazzler. One of these...

and one of these...

Simple & failsafe, provided they're correctly aligned as shown. :D

bdar
12th June 2006, 12:17 AM
Hi Turnerted, you could also use these. Bowl jaw extenion set for your bowl jaws. They come in a set of 3, 14mm, 28mm and 42mm for $85.00. If you do a lot of bowl turning they are great to have, I know mine have payed for themselves. They are made by Enzo Verrecchia from Vermec. Don't have a web site but they are at 39 Dalton Street, KIPPA-RING, QLD. 4670
Ph: (07) 3284 3733 Fax (07) 3284 2733 and email is [email protected]
Hope this will help
Darren

hughie
12th June 2006, 12:55 AM
[. My queary is what is the best way to mount this to clean up the base ? Obviously I can't use my bowl jaws . I tried gripping it using my long reach jaws through the hole but this was not satisfactory and would have marked the neck . I'm sure there must be an easy solution so I await words of wisdom


You could try a donut chuck. But as Ern says with out pic its difficult to give a good answer.

hughie

PHD1
12th June 2006, 01:27 AM
When i finish the bottom on hollow forms I put a scrape in a jaw chuck. Then i turn it to fit the hole in the top of the hollow form. This piece needs a sholulder too. This might take a few tests to get it just right. If you turn the piece a little far you can use something like a papaer towel to take up the space. After u have a snug fit then put it on and bring up the tail stock. You need to be careful not to get to agressive as friction is what makes it spin. At the end i do a little clean up off the lathe were the tails stock was.
Happy turning

OGYT
12th June 2006, 01:55 AM
Turnerted, I do like hughie does, and use a donut chuck... however, for vessels with a domed top, I made a different type of mounting plate. Instead of the flat plate (on the left in Hughie's second pic), I glued 7 pieces of plywood together, and turned a coned-shaped center. Padded with mousepad, it works like a charm to mount a hollowform.
I haven't figured out how to insert a pic in this forum yet, because my pics are on my computer, not a website (url).

OGYT
12th June 2006, 02:09 AM
Figured it out. Here's the pic.

Gil Jones
12th June 2006, 03:13 AM
Geesh Hughie, that donut chuck is nice, but those bolts need to be facing IN, with "T" nuts on the back plate. You got any hands left?

OGYT
12th June 2006, 06:08 AM
I've made mine to use rubberbands instead of bolts and T-nuts. It sure makes it easier on the hands when the rubber bands (instead of bolts) hit accidentally. :)
Just don't get in the way of those screw heads behind it... they're murder!!

Gil Jones
12th June 2006, 11:12 AM
Pretty slick idea, Al.

hughie
12th June 2006, 12:13 PM
Geesh Hughie, that donut chuck is nice, but those bolts need to be facing IN, with "T" nuts on the back plate. You got any hands left


:D yep got most of em. It was a rush job that I have yet to gop back to to fit the tee bolts.

hughie

PHD1
12th June 2006, 02:28 PM
Hi again,

I put a repley in earlier, now i am a little confused. I always understude a hollow form to have a small whole at the top. Most of mine r under 2 inchs. Will this clamping jigs work on something like this?? They look like they r 4 open forms like bowls. Not 2 be cridical, just wondering.
Happy turning

turnerted
12th June 2006, 05:39 PM
Thanks for all the suggestions . Looks like I'll make up a donut .

Skew ChiDAMN!!
12th June 2006, 07:13 PM
I put a repley in earlier, now i am a little confused. I always understude a hollow form to have a small whole at the top. Most of mine r under 2 inchs. Will this clamping jigs work on something like this?? They look like they r 4 open forms like bowls. Not 2 be cridical, just wondering.

A donut-chuck will work on almost any form with a tapered bottom (ie. something for the donut to clamp up to), provided you use some ingenuity on the faceplate end. It can even hold irregular or natural edged forms!

But I know what you mean... keeping a "normal" bowl square to the faceplate is easy, but a true hollow-form with only a small footprint (headprint?) at the lip can be a pain to clamp/centre properly.

I've put a woodworm screw in the middle of my faceplate and I fasten a suitably shaped/sized cone (usually from an offcut) to this. It holds/positions the mouth centrally, while the donut clamps the base. I've found tailstock support is necessary to prevent the donut end from racking under pressure (with disastrous results) but I can live with that. :)

For natural/uneven edged bowls I use a cylinder on the screw instead, to push against the inside bottom of the form instead of the lip. It works for me, anyway. This is more stable (less prone to racking) than the cone method, but a hollow form doesn't usually allow for a wide enough cylinder to be used.

hughie
12th June 2006, 08:12 PM
I've put a woodworm screw in the middle of my faceplate and I fasten a suitably shaped/sized cone (usually from an offcut) to this. It holds/positions the mouth centrally, while the donut clamps the base. I've found tailstock support is necessary to prevent the donut end from racking under pressure (with disastrous results) but I can live with that. :)


Pretty much what I do as well. The plug is turned to suit the opening. I have thought of using a lathe steady for the longer protrusion type forms but have yet to make it up. This was to save using the tailstock.
hughie