Longworth Chuck

[Richard Wilabee]

I have a 16" RMWoodCo Modern Longworth Chuck. I have not used it yet. If anyone has any ideas or pointers while using it that would be appreciated.

Rich

 

[jschnell1203]

Here's the website for it, along with instructions and videos.

http://www.coolhammers.com/longworth_chuck.htm

 

[Gerald Lawrence]

My tips are from my experience and may help some . Use the tailstock against the piece to hold in place. You can work on the piece until you get down to a small tenon (while removing the tenon). Take very light cuts. Once you get the tenon reduced remove the tailstock and manually trim the remaining tenon. Use a soft touch or pad on tailstock to bring up while sanding til you get to the center and then remove tailstock. Remember to use low speeds as the piece will pop out in a hurry at higher ones.
To help opening and closing turn 2 handles so that there is a tenon which will fit in only as deep as the plate on the side is deep. By holding one in the right and one in the left hand will make it much easier to open and close the chuck. For tightening and losening the bolts I use a handle turned and drilled on the end to fit over the wingnuts. Then you can use a drill to tighten by partly tightening a screw on one side the flip over to the other side and continue till all tight. This will center the workpiece.
I do not have pics of these tools right now.

 

[Max Taylor]

longworth chuck-

My computer says the site is expir2ed, Max T.

 

[Justin Stephen]

My tips are from my experience and may help some . Use the tailstock against the piece to hold in place. You can work on the piece until you get down to a small tenon (while removing the tenon). Take very light cuts. Once you get the tenon reduced remove the tailstock and manually trim the remaining tenon. Use a soft touch or pad on tailstock to bring up while sanding til you get to the center and then remove tailstock. Remember to use low speeds as the piece will pop out in a hurry at higher ones.

Agreed. You cannot count on these holding your piece well at all without some additional support if you are taking anything resembling a heavy cut and/or at higher speeds. When I do use mine (which is now pretty infrequently), I center the piece with the tailstock up and take what cuts I can get with the tailstock in place and then duct tape the piece to the longworth chuck for any finishing cuts. Even with the tape, I am taking very light cuts.

 

[Bill Boehme]

My computer says the site is expir2ed, Max T.

Max, I found this link, but all that you get is a log in page. You can register to create a new account, but I don't know or care to see what happens next.

 

[Don Bunce]

Try this:
http://www.youtube.com/watch?v=gMG58c_haqE

 

[Odie]

Is the Ron Brown chuck the same as the RMWoodCo chuck shown at CSUSA?

I think I might have a use for these replacement grippers for the longworth chuck:
http://www.woodturnerscatalog.com/p...-Chuck-Replacement-Grippers-w-Hardware-8-Pack

I put these grippers on my wish list, but what I need to know is the width of the mounting screws....can someone let me know the size of these screws, please?

Thanks

ko

 

[Odie]

Is the Ron Brown chuck the same as the RMWoodCo chuck shown at CSUSA?

I think I might have a use for these replacement grippers for the longworth chuck:
http://www.woodturnerscatalog.com/p...-Chuck-Replacement-Grippers-w-Hardware-8-Pack

I put these grippers on my wish list, but what I need to know is the width of the mounting screws....can someone let me know the size of these screws, please?

Thanks

ko

I know someone here knows the size of these Longworth chuck mounting screws for the rubber grippers......

I'm using jumbo and mega-jumbo jaws with a Stronghold chuck. As long as the bowl walls either slant inward or outward, there is no problem getting a good solid grip with contracting or expanding modes. There is the specific instance when I'm attempting to secure a bowl with vertical walls.......it's problematic. My thinking is these expanding buttons used on the longworth chuck may solve this issue for me if they are used on the auxiliary slots of the jumbo jaws. They might be used as an opposing force to the standard jumbo rubber grippers. If the regular grippers are external, then the longworth grippers could be used internally......or, vise versa.

ko

(I am attaching a photo of the mega-jumbo jaws that shows the long slot in-between the two rows of fixed locations for the regular rubber buttons.)

 

[Max Monts]

OP - If you use the Longworth chuck, tail stock support is CRITICAL. This info is in the instructions, as well. (I added the all caps for emphasis.)
I've tried w/o the support, and bowls went a flyin'. In my case, following the directions results in safe, satisfying bowl bottom finishing sessions.
Odie - Sorry for the delay, but the (hex-socket head) bolts are good ol' 1/4" x 2 1/2".
I can provide a quick pic if needed.

 

[Odie]

OP - If you use the Longworth chuck, tail stock support is CRITICAL. This info is in the instructions, as well. (I added the all caps for emphasis.)
I've tried w/o the support, and bowls went a flyin'. In my case, following the directions results in safe, satisfying bowl bottom finishing sessions.
Odie - Sorry for the delay, but the (hex-socket head) bolts are good ol' 1/4" x 2 1/2".
I can provide a quick pic if needed.

Thank you very much, Max........

No need for a pic......I know what they look like, just didn't know if the diameter of the bolts would fit the slots in my Oneway jumbo jaws. I'll be placing the order now, knowing they will fit.

When holding bowls with vertical walls, the standard Oneway rubber grippers aren't very secure.....especially with weak thin wall bowls. Couldn't apply much pressure......or, enough to make me feel very safe as it was. I don't use a revolving center in the tail stock for finishing the foot, because it doesn't adapt to my "signature" method of doing it. Because of this, the slightest catch could send the otherwise finished bowl into orbit, or worse! For the record, a catch while doing the foot this way has never happened......but, I do fear there might be a first time! This solution applies only to vertical bowl walls, because for the Oneway mega jumbo jaw factory grippers, the grip is extremely secure, provided the walls have a slant to them inward, or outward.

For the Longworth chuck, and as Max suggests.......use a tailstock.....(CYA!) I can see how the method of squeezing the rubber grippers won't be nearly as secure as the grippers on the Oneway jumbo jaws......but, for my purposes as a dual internal/external grip in conjunction with the standard Oneway grippers, they seem to be just what is needed. Being that the Longworth chuck grippers can be adjusted individually, and not dependent on chuck jaw pressure, this seems like an ideal solution to my needs for this one particular application.

KO

 

[hockenbery]

I don't use a revolving center in the tail stock for finishing the foot, because it doesn't adapt to my "signature" method of doing it. Because of this, the slightest catch could send the otherwise finished bowl into orbit, or worse! For the record, a catch while doing the foot this way has never happened......but, I do fear there might be a first time!
KO

Kelly,
Here is a work around.
I did some bowls with bottom somewhat similar to yours a 15-20 years ago using a tailstock and jamb chuck. I had seen someone do one in a demo.
Mount the blank on a screw center. Turn a tenon in a recess, turn the outside of the bowl,
Finish turn the top surface of the tenon, put a couple grooves in the face, mount in the chuck,
Turn out the bowl, reverse with a jamb chuck, turn an attractive element to hide the recess for the Chuck.
For the tail center there are several options simplest is to take out the pin and use a small leather piece to protect the finished bottom, use a wooden cover for the tail center with a leather pad glued on, use one of the soft center covers from rubberchuckie.com

Also, I have seen Stewart Batty turn and finish the bottom of a long stemmed goblet as the first step, grip the bottom in a chuck, turn the goblet, with the bottom finished.

 

[Odie]

Kelly,
Here is a work around.
I did some bowls with bottom somewhat similar to yours a 15-20 years ago using a tailstock and jamb chuck. I had seen someone do one in a demo.
Mount the blank on a screw center. Turn a tenon in a recess, turn the outside of the bowl,
Finish turn the top surface of the tenon, put a couple grooves in the face, mount in the chuck,
Turn out the bowl, reverse with a jamb chuck, turn an attractive element to hide the recess for the Chuck.
For the tail center there are several options simplest is to take out the pin and use a small leather piece to protect the finished bottom, use a wooden cover for the tail center with a leather pad glued on, use one of the soft center covers from rubberchuckie.com

Also, I have seen Stewart Batty turn and finish the bottom of a long stemmed goblet as the first step, grip the bottom in a chuck, turn the goblet, with the bottom finished.

Al......

What?.....give up using a faceplate/wasteblock/jumbo jaws? Forget all the superior advantages of that? Never!

I was using a jamb chuck/tail stock back in the late 1980s......At that time I had the original Nova chuck with the tommy bars, when I first discovered the cole jaws. This is a superior method of doing the foot, and the jamb chuck just isn't an option for me anymore. My methods evolved from there to the jumbo and mega jumbo jaws for the Stronghold chuck. The whole purpose is to avoid jamb chucks and tail stocks......

The Nova chuck and cole jaws are good.....but the Stronghold version is better. Here's a pic of the Nova/cole jaws when I sold it......

ko

 

[Bill Boehme]

It would be worthwhile to verify whether the screw is NC or NF before purchasing them. Most likely it is 20 TPI, but it could possibly be 28 just because the aluminum plate is only about a quarter inch thick and fine pitch would have a tighter fit.

I have Jumbo Jaws, but haven't used them in so many years that I'm not sure where they might be. They might be OK for finishing the foot, but their lack of precision alignment make them a problem for things that require accurate alignment. Of course, vacuum chucking and other methods that use rubber or other soft gripping may not be much better. The biggest drawback for me is that they aren't satisfactory for holding warped turnings.

 

[Odie]

It would be worthwhile to verify whether the screw is NC or NF before purchasing them. Most likely it is 20 TPI, but it could possibly be 28 just because the aluminum plate is only about a quarter inch thick and fine pitch would have a tighter fit.

I have Jumbo Jaws, but haven't used them in so many years that I'm not sure where they might be. They might be OK for finishing the foot, but their lack of precision alignment make them a problem for things that require accurate alignment. Of course, vacuum chucking and other methods that use rubber or other soft gripping may not be much better. The biggest drawback for me is that they aren't satisfactory for holding warped turnings.

Hi Bill.....thread size doesn't matter, as they will be used in the slots.

ko

 

[hockenbery]

Al...... What?.....give up using a faceplate/wasteblock/jumbo jaws? Forget all the superior advantages of that? Never! I was using a jamb chuck/tail stock back in the late 1980s......At that time I had the original Nova chuck with the tommy bars, when I first discovered the cole jaws. This is a superior method of doing the foot, and the jamb chuck just isn't an option for me anymore. My methods evolved from there to the jumbo and mega jumbo jaws for the Stronghold chuck. The whole purpose is to avoid jamb chucks and tail stocks...... The Nova chuck and cole jaws are good.....but the Stronghold version is better. Here's a pic of the Nova/cole jaws when I sold it...... ko

I used the jumbo jaws for a while. They work great! The downside for me were the things you are experiencing plus some other:
that the jumbo jaws were too limiting on rim design and not practical for natural edge bowls, large bowls, square edged bowls, or really thin bowls.
I use a vacuum chuck on occasion which give complete access to the bottom.
Mostly I just jamb chuck as it is quick reliable and if needed I can turn anywhere on the bottom except for a tiny 1/8" diameter center area.
When I don't have much working room I use inserts for the tail center from Bruce Campbell.

http://www.artisansworkbench.com/Product info/Extension Points/extension_points.htm

Al

 

[Gerald Lawrence]

I have cole jaws for both Nova and Pennstate. Also have a Longworth made by member from another club. I use the longworth most. Also have long pins for the Pennstate and they are great for some irregular shapes if the piece is small enough. I mostly use the longworth, however as Bill said centering is sometime a problem, but still my best solution on larger pieces.
Have had an improved result due to time and experience with jam chuck with a piece of innertube on the point and tail stock pulled up. This method does take some patience and will improve with practice. For me I only use this on irregular shapes or if does not fit any other method.

 

[Odie]

I used the jumbo jaws for a while. They work great! The downside for me were the things you are experiencing plus some other:
that the jumbo jaws were too limiting on rim design and not practical for natural edge bowls, large bowls, square edged bowls, or really thin bowls.
I use a vacuum chuck on occasion which give complete access to the bottom.
Mostly I just jamb chuck as it is quick reliable and if needed I can turn anywhere on the bottom except for a tiny 1/8" diameter center area.
When I don't have much working room I use inserts for the tail center from Bruce Campbell.

http://www.artisansworkbench.com/Product info/Extension Points/extension_points.htm

Al

Yes, you are correct, Al......you can't use jumbo jaws for natural edge bowls......

As long as we're discussing alternative methods, there is the Grumbine chuck. The Grumbine chuck is a mechanical alternative to vacuum chucks that works very well for the occasional natural edge bowl. These photos were taken just after I made mine, and I had yet to get a set of sized bolts for any application. As shown, it would represent a dangerous situation, with the long protruding bolts. The compressed toy ball is my invention, but I wouldn't be surprised if I'm not the first to think of that! There is a leather covering on the outer plate opening, where the foot is turned.....also, without the need for a tailstock. I do an occasional natural edge bowl, but it's not my main effort. The Grumbine chuck is a good way to inexpensively handle the need......

ko

 

[hockenbery]

Hi Kelly,

I would be hesitant for giving Bill G. credit for inventing this chuck.

I was introduced to this chuck by Bob Marshall in the mid 1990’s.
Alan Lacer wrote an article on it and named it the Straka Chuck, see AAW Journal article "The Straka Chuck," 23.1:50–53.

I use the chuck to hold balls and have a handout on constructing one.
Using a PVC standoff it can work for small deep natural edge bowls.
A Straka chuck to hold a 15-16" diameter natural edge bowl gets to be enormous.
And they don't work for shallow bowls
I never found it practical for natural edge bowls.
Most of my natural edge bowls now are footless with round bottoms easily turned on a jamb chuck.

 

[Shawn Pachlhofer]

Al - can you provide a link to making this chuck for holding a ball?

I have a hollow ball I'm working on and think this would be the best method for completing the tenon "end" of the ball.

thanks!

 

[hockenbery]

Al - can you provide a link to making this chuck for holding a ball? I have a hollow ball I'm working on and think this would be the best method for completing the tenon "end" of the ball. thanks!

Hi Shawn,

Here is a link to the handout.
http://aaw.hockenbery.net/Making a straka Chuck.pdf

When I make the opening you want the shoulder of the 45 degree cut to rest on the ball
You may need to do something else for your needs.

My method is a quick and dirty for woodturners and not suitable for those with cabinet maker skills.


Have fun, work safely

Al

 

[Shawn Pachlhofer]

Perfect, Al - thank you very much!

 

[Odie]

The Longworth rubber grippers and hardware arrived on Thursday. Tried them once, and they are good to go......perfect fit in the Oneway slots. If they save one bowl at sometime in the future, that'll pay for them. Like I said, I've never lost a bowl because of less-than-perfect grip on vertical walled bowls, but Murphy's law says that sooner or later, I'll have a catch that'll do it!

ko

 

[Odie]

Sometimes, new doors are opened by using tools in unimagined ways.........

(Darn it.....wish I had taken a photo of this, while it was on the lathe!)

I used the Longworth grippers yesterday in the slots of my Oneway Jumbo Jaws, to secure a natural edge Red Box Elder burl dish.....! Yes, you heard that right.....a natural edge turning on the Jumbo Jaws! The Longworth grippers were used in conjunction with the standard Oneway grippers.

The Longworth grippers need a way to grip the Jumbo plates, or they will slide at higher rpm's. This is taken care of by adding some "star" locking washers on the back side of the plates.

The turning was only contacting the jaws at a couple small points, as I adjusted the level to more closely match the foot area left by the waste block. These Longworth grippers do an excellent job of holding the turning "in mid-air". This is probably not a good idea for large turnings, but this piece is only about 6x2", but with a very ragged and uneven edge.....

This opens up new possibilities for me, now that I've made this discovery!

The Red Box Elder wood was a very slim piece of a burl cap cut off. I've tossed out several of these before, because they seemed unusable with my equipment. (Those of you with vacuum chucks can do this easily. I have a Grumbine chuck that is just too big to do this little burl cap.)

It's a good feeling to know you've expanded your horizons......!

If I think of it, I'll try to get a photo of this little Box Elder burl dish later on. As you might be able to tell, I'm pretty excited about this new option I've discovered! Some will say, "Just get a vacuum chuck".....and, from my point of view, that's a pretty hefty expense/effort to cover something I seldom have a need for......

ko

 

[Rob Wallace]

Some will say, "Just get a vacuum chuck".....and, from my point of view, that's a pretty hefty expense to cover something I seldom have a need for......

ko

I have said this for years: "Once you go VAC, you'll never go back!"

You don't know what you're missing until you try it - you have just demonstrated that with your new grabbers.

Over the years, my vacuum chuck system has saved me so much time and many individual, unique pieces from becoming waste that it has paid for itself several times over.

Vacuum chucking is a proven method - don't dismiss the so-called 'hefty expense' because of a perceived "seldom have a need" situation. A scroll chuck might be perceived as a 'hefty expense' by users of face plates, but the versatility and efficiency chucks provide make them almost a necessity for many (perhaps most) woodturners. The same could be said for any kind of new woodturning equipment which expands your capacities, capabilities, and expertise as a woodturner. Vacuum systems are not THAT expensive, and they provide a lot of great workholding opportunities.

Rob

 

[Odie]

I have said this for years: "Once you go VAC, you'll never go back!"

You don't know what you're missing until you try it - you have just demonstrated that with your new grabbers.

Over the years, my vacuum chuck system has saved me so much time and many individual, unique pieces from becoming waste that it has paid for itself several times over.

Vacuum chucking is a proven method - don't dismiss the so-called 'hefty expense' because of a perceived "seldom have a need" situation. A scroll chuck might be perceived as a 'hefty expense' by users of face plates, but the versatility and efficiency chucks provide make them almost a necessity for many (perhaps most) woodturners. The same could be said for any kind of new woodturning equipment which expands your capacities, capabilities, and expertise as a woodturner. Vacuum systems are not THAT expensive, and they provide a lot of great workholding opportunities.

Rob

I have no doubt you are right, Rob......

If I had a vacuum chuck, I'd find it superior to what I just did with the Longworth grippers.....I believe that unquestionably.

The last time I could have used a vacuum chuck might be five or six years ago! I believe, since I've got so many things I'm already pursuing with my lathe turning, which include investment of time/energy/money, I believe I'll just leave natural edge turning to those who are more interested in it.

Yes, I am a faceplate turner, but did you know I have three Stronghold chucks, and use them all? I know this is a matter of opinion, but mine is that faceplates are superior to chucks when finishing a bowl.

later, Rob.......

ko

 

[Bill Boehme]

I put together my vacuum system for a total cost of around $100 by finding a used pump on eBay and then making my own rotary coupler and chuck. There was a fellow selling complete systems at SWAT last summer for around $150, IIRC (with a real vacuum pump and not a Venturi). There is hardly anything where a vacuum chuck would be the only solution to holding a turning, but it is so quick and easy that it became my method of choice for reverse chucking. I saw that Craft Supplies sells Longworth chucks from $140 to $300 depending on size. Of course, you can make your own for less. A vacuum system doesn't look so expensive compared to that price.

About chucks and faceplates, both have their strong points and I use both although I generally use chucks because of their convenience.

 

[hockenbery]

I find the vacuum extremely flexible in what is can hold.
I make my chucks from wood, PVC, and Sona tube.
Vacuum will hold balls for hollowing, wide platters , bowls of almost any size, with PVC stepped down to 2" and used rubber chuckie inserts to hold finials inside the chuck to turn on the the bottoms of the final bases.

I prefer turning most bowl and HF bottoms on a jamb chuck.

I turn most hollow forms on a faceplate Most bowls on a chuck.
al