Modern Longworth Chuck

Dan Mosley

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Palm Springs, Ca
I saw this video on the Modern Longworth Chuck - I do not own one but it seemed to be a handy tool. You can buy additional teflon like washers that drop over the holders to rise it up so you do not hurt the rim on thinner turned edges.
http://www.youtube.com/watch?v=6aeZZ3U51Xs

Comments state you can use it on vessels - however I can not imagine that.............

If anybody has one I would like to know if it is as secure to use at they show in the video.......................

I have 2 chucks both are SN2 one with power grip jaws and the other with spigot jaws - not sure if it would fit into them either.......anyway let me know if any of you have used one................
 
I've used a shop-made Longworth chuck. It was well-made and had six bumpers on it. It's the only chuck I've ever had let go of a piece, which subsequently hit me in the head. So I'm a bit biased against them. ;) One issue with any Longworth chuck is that they only work on round pieces. Warped or natural edge stuff won't be held securely. Even perfectly round pieces are only held relatively lightly. Low speeds and light cuts are a must.

The one in the video you linked to looks like the Cadillac of Longworth chucks, though.
 
I've used a shop-made Longworth chuck. It was well-made and had six bumpers on it. It's the only chuck I've ever had let go of a piece, which subsequently hit me in the head. So I'm a bit biased against them. ;) One issue with any Longworth chuck is that they only work on round pieces. Warped or natural edge stuff won't be held securely. Even perfectly round pieces are only held relatively lightly. Low speeds and light cuts are a must.

The one in the video you linked to looks like the Cadillac of Longworth chucks, though.
 
What would be the advantage of the Longworth over a Colejaw? The longworth looks more "Rube Goldberg-ish" to me where the Colejaw seems far more simple to operate and it looks as if you could get better holding power because it operates off the chuck jaws.

I could see one of those carriage bolts binding just enough to not give you the hold you think you have on the piece. Also, the wear is going to be more prevalent on those spiral ways as opposed to the stationary posts of the Colejaw.
Just my observation looking at the two. I have no experience with either but that is what I see looking at the two.
 
I've used a shop-made Longworth chuck. It was well-made and had six bumpers on it. It's the only chuck I've ever had let go of a piece, which subsequently hit me in the head. So I'm a bit biased against them. ;) One issue with any Longworth chuck is that they only work on round pieces. Warped or natural edge stuff won't be held securely. Even perfectly round pieces are only held relatively lightly. Low speeds and light cuts are a must.

The one in the video you linked to looks like the Cadillac of Longworth chucks, though.

You've all seen the pictures of my black eye... I got it when a bowl jumped out of my home made Longworth. They do work and are handy for holding bowls that won't fit in my cole jaws, but the hold is NOT as secure as the cole jaws... at least on the home made version I have... you have to position and move the pins individually to the edges of the bowls and make sure you are centered in the jaws. I find mine useful, I don't use it a lot and like Vaughn, I'm a little biased against it and a little gun shy of it.... definitely no speed over 450 or 600(and 600 is risky) on mine, VERY light cuts and the tails stock is an absolute must until you get to the little nub in the center... that I usually take away now with a chisel and sander.

The one in the video looked as if it would self center, so that would be more practical than my home made that you have to move each pin... my Longworth has 8 pins, so it's a little time consuming to get it right.
 
What would be the advantage of the Longworth over a Colejaw? The longworth looks more "Rube Goldberg-ish" to me where the Colejaw seems far more simple to operate and it looks as if you could get better holding power because it operates off the chuck jaws.

I could see one of those carriage bolts binding just enough to not give you the hold you think you have on the piece. Also, the wear is going to be more prevalent on those spiral ways as opposed to the stationary posts of the Colejaw.
Just my observation looking at the two. I have no experience with either but that is what I see looking at the two.

The primary advantage of the Longworth over the Cole jaws, at least in my shop is that my Cole jaws will only hold a bowl up to about 8 1/4 inches diameter... anything bigger and I have to go to some other hold... the Longworth I made will hold a bowl up to about 11 inches... the disc I made is 13 7/8 diameter so it will turn over my ways... I have a Jet 1442 so that is the largest diameter I can take .... I have since bought the PSI Cole jaw extensions and when I put them on the Cole chuck I have to turn the headstock 90 degrees outboard(the extension jaws open to about 16 inches) and put the funky tool rest on the lathe and I can usually finish a bowl that way.... with the extensions I can hold a bowl up to about 15 inches although I've never made one that size. I trust the Cole jaws more than the Longworth, but with it out board I can't use the tailstock and that's a little nerve racking...
 
I am a bit biased to. I won't use a longworth chuck. I had 3 pieces fly out of the one I had and sold it. I do have cole jaws but only use them on occasions. Mostly I use donut chuck or vac chuck.
 
Although I do have a Longworth chuck I'm less than enthusiastic in using it as I have never found a way of applying enough force to grip securely before clamping.
My solution has been to bite the bullet and fork out on Commercial Cole Jaws (buying material an making my own was a factor of 4-5 dearer)
Initially to extend their range on a 100mm (4") chuck I made up some adaptor plates. This still had the limitation on a 100mm chuck of th next bowl you wanted to mount was between the available jaw movement range.

_________ ___ ___ ___ click on images for larger view
___________Eight 7/8 x 1/4" pieces of steel, 48 Holes, 32 of them tapped 6mm.
__________Not something you would want to poke a finger in, but no worse than a square or natural edge bowl.


The solution has been to acquire a 150mm (5") chuck with a 40mm diam. jaw travel, which is greater than button footprint and location hole spacing.
Details of the advantages of a 5" chuck body can be seen in this UKW Forum post.
 
Hmm, I have a set of cole jaws and two Longworth chucks. The Longworths are shop made and are my preference over the Cole Jaws.

What I have found you need to have a variety of different shaped jaws for the Longworth. This will give you much better gripping power, just using one type is not going to work all the time.

I think what you use them for has some bearing as well, for me its just for finishing the bottoms of bowls etc. I have one lathe set up with my bigger Longworth [24"] and its just for finishing bottoms.

As for the 'modern type' they appear to be very the same as the original other than that they most likely are cnc made and should be far more accurate.Thats a good thing :thumb: curious number of sizes tho' :dunno:
I find with my 24" and 12" I can do all that I want. The 24 will go down to about a 8" bowl and the 12 will do as small as a 3" bowl.
 
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