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hughie
27th August 2006, 03:54 PM
The Leady Chuck

Its a simple affair, but works very well. It has been designed for use in NSW High Schools and apparently its been there for many years. Designed and built by Bruce Leadbetter in his Sydney shed/workshop.
The centre cone is wound in to meet the job and then you just spin the work till it bites and a way you go. If you have a jam up and the chuck spins and tightens further.
He supplies a cutter to produce the right dia and depth of recess and once you have set the centre cone to its a simple job to attach your blank.The recess is about 55mmx6mm deep [2.1''x 1/4'']
To remove, simply spin in the other direction to release the jaws.

Wood Butcher
27th August 2006, 05:10 PM
The school I've been doing some prac teaching at would have at least 12 of those chucks and only 2 4 jaw scroll chucks. (and only 4 lathes).

They are simple for the kids to use and very hard to damage!

TTIT
28th August 2006, 12:36 AM
Hughie - I was trying to come up with something similar years ago but couldn't work out how to keep enough pressure on the jaws against the back plate - Looks like it just creates the pressure itself? Looks like the size of the recess would be fairly crucial - would it hold in a forstner-cut hole??? Are the things on top of the cone spikes to grip the bottom of the work??? - bit hard to tell in the pic. Have you used it yourself?? Is it any good???? etc? etc? Need a full review here I think.;);):D:D

OGYT
28th August 2006, 02:38 AM
"Looks like the size of the recess would be fairly crucial - would it hold in a forstner-cut hole??? Are the things on top of the cone spikes to grip the bottom of the work??? - bit hard to tell in the pic. Have you used it yourself?? Is it any good???? etc? etc? Need a full review here I think.;);):D:D"
TTIT, I second that!
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hughie
28th August 2006, 10:46 AM
. Have you used it yourself?? Is it any good???? etc? etc? Need a full review here I think.;);):D:D
[/QUOTE]

Vern, Al 'n all,
Have not used it, only seen it in action. This chuck belongs to a buddy who is on holidays for a month. Its been in use for many years in the NSW High Schools as simple and effective chuck for teenage boys who like to work things to the limit. Bruce has sold a lot of them and each one of his lathes goes out with one on.

Maybe some more pics might be in order. As I say I have not used it so here goes my understanding of it.

The jaws are Aluminium and are in three pieces held to gether by a spring around the outer edge in a groove.see jpg73,72 If you look carefully at jpg72 you will see a ridge on the smaller dia furtherest away from the spring. This is the portion that sits in the recess of the work, the ridge does the holding as it bites into the timber.

There is a cone or tapered section to the centre of the jaws. see jpg73.
Into this is screwed the central steel cone piece see jpg74 This is attached to the bolt on the main body of the chuck see jpg75.

The recess is produced by a supplied cutter that is much like a Forster bit, you then wind/set the centre steel piece in to meet the dia of the recess. Place the work piece on the chuck rotate the work anti clock wise until it grips. It goes with out saying that you have locked the spindle on the lathe before hand. To remove is the reverse process. Generally speaking once the chuck is set you can on and off various work pieces without touching the cone piece.

The base of the chuck or main body looks like his standard small face plate. Bruce reckons it can swing anything up to 29'' no sweat.

My buddy swears by it, all I have to do now is get an adapter 1''BSW 8TPI to m30 3.5 pitch, not real common...:(

hughie
28th August 2006, 10:54 AM
sorry lost the pics somewhere?????? here they are!

TTIT
28th August 2006, 11:38 AM
Too easy!!! Geez Hughie - now you've gone and done it again!:eek: Looks like a couple of hours on the SIL's metal lathe comin' up!;) :D :D

Zsteve
29th August 2006, 02:14 PM
While not trying to take anything away from the maker of this one. This chuck looks quite similar to the Woodfast Superchuck that was around in the late 80's. It had the central tapered plug that screwed in like that pictured, it also had the aluminium split expanding jaws etc etc.

It just screwed on a face plate - and would work on any faceplate with a half inch thread in the middle of it. It worked quite well.

I actually have the collets and taper centre bit for sale if anyones interested in making a resonable offer, all you would need is a face plate with a half inch thread in the middle. Collets fit into a ~75mm diameter recess about 8mm deep.

I also made a smaller dovetailed type one which worked well.

Regards
Stephen

Gil Jones
30th August 2006, 02:06 AM
Thanks, Hughie.

hughie
30th August 2006, 09:52 AM
Steve can you pm me with some pics and a price? I am interested, but need a look at it first, ta

Regards
Stephen[/quote]

OGYT
30th August 2006, 02:40 PM
Late gettin' back... thanks, Hughie. I'd like to watch it in action.