Stronghold vs. Talon Chucks

[Joseph Maiorano]

I've been turning with a Talon chuck for years and never had a problem. Every so often I think about upgrading to a Stronghold. Other than the larger size and extra mass, what's the difference?

Also when turning larger bowls, 10"- 14", I noticed I get a lot of noise/chatter on the second turning on the inside of a twice turned bowl. I am wondering if the extra mass of the Stronghold chuck will absorb some of the noise?

Thanks

 

[Doug Freeman]

In addition to chuck size and overall mass, the ring gear is a larger diameter so for equal torque on the chuck key more force is applied through the jaws.

The Stronghold may help with some of the chatter some of the time. I use a piece of leather in my left hand pressed against the side of the turning when vibration is an issue. What tool and size are you using, and does it occur near the rim only? I've found a smaller tool (3/8" gouge) vs the 5/8" I use most of the time really helps with rim vibration by reducing the cut force. I use the 3/8" for 1-2" down, more if needed on a NE bowl to get below the lowest rim dip.

Also depends on your mounting method/attachment size. What jaws do you use and typical recess/tenon size for a bowl, ie % of bowl diameter? Small attachment methods, which increase bowl side length, play a role as well.

 

[Don Wattenhofer]

The larger chuck will not stop the chatter on the larger bowls but it will provide a larger tenon or recess. The problem you are experiencing is likely the wood flexing. The solution is to finish the inside first then jam chuck to do the outside. Stuart Batty has a video that shows this technic.

 

[Joseph Maiorano]

These bowl were initially turned with a #2 jaws. I've since switched to #3 jaws for the larger bowls. The last set of bowls I rough turned were with the #3 jaws and have not finished any yet. I still have a few to get through with the smaller jaws. I'll have to find the Stuart Batty video.

Thanks,

 

[Doug Freeman]

Stuarts video

View: https://www.youtube.com/watch?v=N7BjRcSDurM&list=PLdWw7w_lu91QbqyhRXJJ3_N2A-yLymE0W&index=16&t=1303s

 

[john lucas]

The chatter is most likely pushing on the bevel too hard.. sharp.tool, light cuts and try not to put any more pressure on the bevel.than necessary. I find using a more acutely ground edge helpful for this but might only be able to use it for a few inches down the bowl.

 

[hockenbery]

I've been turning with a Talon chuck for years and never had a problem. Every so often I think about upgrading to a Stronghold. Other than the larger size and extra mass, what's the difference?

Also when turning larger bowls, 10"- 14", I noticed I get a lot of noise/chatter on the second turning on the inside of a twice turned bowl. I am wondering if the extra mass of the Stronghold chuck will absorb some of the noise?

Thanks

You will have a larger tenon with the stronghold #2 or #3 jaws.
The larger tenon might reduce the chatter some.

main causes of chatter
1. Not having enough wood mass between the mounting point and the cut to take the amount of cut.
A stair step on the inside wall leaves supporting wood in the bottom.
Sharper tools, lighter cuts, adjusting the feed rate All help

2. Too much tool overhang for the cut you are making.
Sharper tools, lighter cuts, adjusting the feed rate, Larger diaper tool, move the tool rest. Sturdier tool rest

3. Too much bevel drag
grinding the heel off the bevel. Float the bevel,
gripping to tool too tightly, let the tool work while you gently guide it

4. Not riding the bevel

check out the mounting and returning a dried bowl video in the thread below to see how I leave mass in the bottom of the bowl.
http://www.aawforum.org/community/index.php?threads/working-with-green-wood.11626/

 

[odie]

The chatter is most likely pushing on the bevel too hard.. sharp.tool, light cuts and try not to put any more pressure on the bevel.than necessary.

To add to John's post, another major component is rpm.

I remember years ago, going with as high an RPM as I could stand, but because we are all evolving, I've changed my philosophy on that. RPM is one of the most important components of the turning equation. The best RPM is that which eliminates as much harmonic vibration as possible. Each piece of wood is an "individual", and between one piece of wood, and another, even those that are the same size and shape, the best RPM may not be the same......because their center of gravity is almost never exactly the same. Sometimes, as little as 25 RPM adjustment can make a major difference in the cut that is possible.

Sharp tools, tool choice, presentation, and good technique are all equally as important.

The ultimate objective is to have good shape, and end up with a surface that requires as little sanding as possible.

-----odie-----
.

 

[Charlie Knighton]

I believe major difference is sh for larger mass ..... t u can work around the foot better without reverse chucking

imo sh is more versatile because u are going to have to reverse chuck any way u look @ it unless u do the ole flat bottom and cover with felt from overseas trick

 

[Don Wattenhofer]

1. Not having enough wood mass between the mounting point and the cut to take the amount of cut.

Almost all rough turned bowls go oval as they dry therefore the inside should finished first to take advantage of the mass since there is no practical way to support the outside with a jam chuck. The only way I can think to do the outside first is to go extra heavy on the walls so you have the necessary mass to finish the inside, then live with a heavy clumsy bowl.

A stair step on the inside wall leaves supporting wood in the bottom.

The stair step method will work however the concave surface on the inside is hard to eliminate tool marks at each of those steps, unless you don't mind marathon sanding.
Well I better stop now that I have stepped on some toes or egos.

 

[hockenbery]

The stair step method will work however the concave surface on the inside is hard to eliminate tool marks at each of those steps, unless you don't mind marathon sanding.
Well I better stop now that I have stepped on some toes or egos.

the key to a successful stair step is to pick up the finish cut before each transition mark and not leave any transition marks.
Most bowls can be sanded with 220.

Also with most functional bowls the walls will be 3/8 or thicker so a final pass over the bottom 2/3 of the wall is easily achievable after stair stepping.

 

[hockenbery]

Almost all rough turned bowls go oval as they dry therefore the inside should finished first to take advantage of the mass since there is no practical way to support the outside with a jam chuck. The only way I can think to do the outside first is to go extra heavy on the walls so you have the necessary mass to finish the inside, then live with a heavy clumsy bowl.

Turning the inside first is intriguing. Never seen it done. But you have the most out of balanced wood in the rim and outside walls. Seems too hard. I like easy.
Be interested in seeing a video of your inside first technique.

It is easy to jamb chuck the warped bowl over a chuck with the jaws open. Also while doing it you can line up the highs and lows of the warped rim to get the largest bowl from the dried blank.
When I do the outside I try to take off the least amount of wood to get the bowl round with a pleasing curve.

there is not much warp in the bottom so it is easy to leave mass there.

since you are going to turn down the inside walls there isn’t any concern about leaving them thick.
They can be be turned to any desired thickness

take a few minutes to see how I return a really warped bowl in a demo.

Mounting and turning a dried bowl

View: https://www.youtube.com/watch?v=sCZWsHB4vlM

 

[Bill Boehme]

Bigger isn't necessarily better. The size of chuck that you need should be dictated by the size of the piece of wood. A rough rule of thumb is to use a Talon for bowls under 16 inches diameter. The smaller diameter Talon allows easier access to the area close to the tenon. My Robust American Beauty lathe has a swing of 25½", but I mainly use Talon chucks.

 

[Don Wattenhofer]

the key to a successful stair step is to pick up the finish cut before each transition mark and not leave any transition marks.
Most bowls can be sanded with 220.

I totally agree as I have used that method for many years on the translucent goblet forms but it is on the outside convex surface.

Turning the inside first is intriguing. Never seen it done. But you have the most out of balanced wood in the rim and outside walls. Seems too hard. I like easy.
Be interested in seeing a video of your inside first technique.

Just look at the Stuart Batty Video

 

[hockenbery]

Just look at the Stuart Batty Video

watched the video above.
I did not see him return a dried warped bowl.

in the demo he turns the outside, then turns the inside, then puts it on a jamb chuck turns part of the outside thinner up to 2” from the rim.

Using the technique in the video for a dried warped bowl, you would turn the outside and true the tenon, turn the inside leaving the wall thicker an inch or two below the rim, jamb chuck it and then turn the wall you left thicker down to the rim thickness or a little less than the rim thickness.

 

[Joseph Maiorano]

Yesterday I finish turned two bowls, maple and cherry around 10" in diameter, which have been on the shelf drying for nearly two years. When it cam time to do the inside, I paid careful attention to everything mentioned above ... feed rate, RPMs, pressure, sharpness, tool size, presentation, etc. I came to the conclusion there are too many variables and what worked on the maple bowl did not necessarily work on the cherry bowl. The one thing which made the biggest difference was the feed rate of the tool and patience. Letting the wood come to the tool produced the best cut.

Thanks for all your help.

 

[hockenbery]

came to the conclusion there are too many variables and what worked on the maple bowl did not necessarily work on the cherry bowl. The one thing which made the biggest difference was the feed rate of the tool and patience. Letting the wood come to the tool produced the best cut.

Be proud of your two bowls.
Two and a half lessons well learned.

So many variables the biggest issue in teaching is trying to limit how much to give new students. Need to avoid information overload so that they remain receptive to the more important elements.

letting the tools do the work

the half lesson- We all find pieces of wood that require different techniques. Highly figured wood, punky wood, exceptionally soft or hard woods. the basic gouge cutting techniques will work on almost all species down to the final surface. the last 1/32 to 1/64 may need special attention with a different cut or a scraper.

I use the same gouge techniques for cherry and maple. Some of the soft maple do Not to like to be scraped.

 

[Don Wattenhofer]

Using the technique in the video for a dried warped bowl, you would turn the outside and true the tenon, turn the inside leaving the wall thicker an inch or two below the rim, jamb chuck it and then turn the wall you left thicker down to the rim thickness or a little less than the rim thickness.

Using the technique in the video for a dried warped bowl, you would turn the outside and true the tenon first then mount it in your scroll chuck and finish turn the inside etc. The inside first method is something I have done for many years when making end grain translucent (that is walls less then 1/16th") goblets where I leave the majority of the wood mass outside of the cup for stabilizing. The part of the video where he mentions the spiraling cut on the inside caused by the wood flexing made me wonder why I never thought to try it on side grain bowls.

This birch burl bowl was rough turned in 2015 to approximately 1" wall thickness and after finally getting the inside finish turned I found 2 areas of the outer rim that would require cutting down to about 1/6th" wall thickness to cut away the last of the Ankor seal. The jam chuck turned into more of a form fitting support with the live center holding it. I realize that this is not what the video demonstrated but it did jog me into solving another similar problem. I have since tried successfully to use the method on a standard side grain rough turned cherry bowl where I jammed it onto the outer rim only and finished the entire outside without the live center support. So keep an open mind you don't have to do exactly like the demonstrater demonstrates.

 

[hockenbery]

inside first method is something I have done for many years when making end grain translucent (that is walls less then 1/16th") goblets where I leave the majority of the wood mass outside of the cup for stabilizing.

everyone turns the inside first on thin walled endgrain vases and goblets because the wood structure won’t support hollowing without cracking.
We both know End grain is different than side grain.

Appreciate seeing your experiment.

Stewarts method won’t work on side grain NE bowls. Those are easily turned to thin walls if they aren’t too large.
Under an 1/8 is pretty easy for a 10”, under 1/4 pretty easy for a 15”.
Johannes Michelson gets really thin on his hats. He can do one 1/16Th and probably at 1/32.

I have turned some hollow balls by splitting a rough turned ball along the grain lines, hollowing each part and gluing back together. Then turning the outside of the ball to finish. Here you know the inside diameter so you can keep the outside diameter larger.

Stewart Batty is one of the best turners in the world. Easily in my top ten.
As for bowls - I appreciate what Stewart does but see no return for that expenditure of effort.
And I don’t have to compensate for not using an Ellsworth grind

 

[Don Wattenhofer]

Stewarts method won’t work on side grain NE bowls.

Yes but a variation of it does work for NE side grain bowls, but like you say it is not always necessary as it was for my Birch burl NE bowl. There is another factor if doing once turned bowls the green wood cuts better and has not warped yet.

And I don’t have to compensate for not using an Ellsworth grind

Did I miss something in the video I don't understand this comment but then I don't have or use the Ellsworth grind or any of the similar types.

 

[hockenbery]

Did I miss something in the video I don't understand this comment but then I don't have or use the Ellsworth grind or any of the similar types.

you missed the smiley faces. Sort of a joke but...

Finishing the inside of the bowl I use an Ellsworth grind with the flute up doing a shear cut.
This cut has almost no bevel drag, a high shear angle, cuts from near the rim of a cut rim bowl and from the rim of an NE bowl, cuts to bottom center on any bowl that is not significantly higher than wide.
It leaves a 220 surface most of the time unless the wood has wild figure.

 

[Bill Boehme]

When making a basket illusion piece I turn the inside first. That presents a challenge to me because I can't look at the inside and judge whether it has the contour that I want. This is so much easier to do when turning the exterior, but there's no horizon to see when looking at the interior. My solution is to create a CAD drawing and then printing it full scale so that I can make a cardboard template to fine tune the inside curve.

 

[Don Wattenhofer]

When making a basket illusion piece I turn the inside first. That presents a challenge to me because I can't look at the inside and judge whether it has the contour that I want. This is so much easier to do when turning the exterior, but there's no horizon to see when looking at the interior. My solution is to create a CAD drawing and then printing it full scale so that I can make a cardboard template to fine tune the inside curve.

I find that I can feel the inside contour better than see it, that only works when you don't have the kind of issues like matching beads inside and out. I did a similar CAD generated template making a domed lid for a box using Hans W's pierced method. The inside and outside arcs had to be based on the same center-point with the radius of the outside arc being the thickness + the inside arc radius. The inside grooves wire cut with the same axis as the overall lid but for the outside grooves I needed to make an angled block ( the angle was determined using CAD) to such that the outer arc turned within it's radius.