Off-center Tailstock live center.

[Nick Valenza]

Hello all! The attached piece was turned 3mm off center. I wanna test going further than 3mm, but I am afraid that the stem will snap, as it doesn't go back between centers until the base gets started. Besides making something, had anyone ever heard of blue fox tools?
Off center live center
i could add soothing to the cone to make it fit the goblet cup.

Anyone know of any off-center, live center tailstock support?

 

[Paul May]

This is seriously cool. Very well done!

 

[William Rogers]

Very well done Nick. I have not seen/heard of the blue fox tool. I have the Axminster eccentric chuck.

 

[Michael Anderson]

I have not heard of that center before, but it looks pretty cool!

 

[Don Wattenhofer]

I know that machine lathes often have a feature that allows the tailstock center to be offset and I think that some of the Delta lathes made before about 1950 also had that feature. See the thread about "boring heads" you could maybe adapt a live center to mount in a boring head and use my method to mount the boring head to the quill on the tailstock.

 

[Don Wattenhofer]

I have not heard of that center before, but it looks pretty cool!

This reply came up as I was writing my reply so I went back and looked at the Blue Fox tool and that is essentially the same as a what I proposed. The only thing I would be concerned about is the single point center that may require more pressure on the work piece then you would want to apply to a fragile piece like you have so a cup center would be better.

 

[Nick Valenza]

This is seriously cool. Very well done!

Thank Paul! I appreciate your kind words!

 

[Nick Valenza]

Very well done Nick. I have not seen/heard of the blue fox tool. I have the Axminster eccentric chuck.

Thanks Bill. I haven't heard either until I did that google search. I appreciate your feedback!

 

[Nick Valenza]

I have not heard of that center before, but it looks pretty cool!

Thanks Mike and I appreciate your response!

 

[Nick Valenza]

This reply came up as I was writing my reply so I went back and looked at the Blue Fox tool and that is essentially the same as a what I proposed. The only thing I would be concerned about is the single point center that may require more pressure on the work piece then you would want to apply to a fragile piece like you have so a cup center would be better.

If all else fails, I was gonna make a cone center, with a cone on the undertbe cone, to fit thr cone in the tool, and then use double pressure tape to secure the cone center to the off center cone on the tool in the link.

 

[Dave Landers]

If it were me, I'd probably turn a 2-piece thing. Turn a cone (or whatever support is needed for your cup). Then I'd make a disc with some way to attach it to my live center (for a powermatic/jet/oneway/robust, that'd be a 3/4-10 nut epoxied in). Then use double face tape or hot glue or whatever to attach the two pieces together at the desired offset. At least that'd be my initial/test version.

 

[Daniel Henry]

Vicmarc offers an Eccentric chuck.

 

[R Henrickson]

Much eccentric turning can be done without an eccentric chuck. I have one but don't use it in any of my multiaxis turning. At meeting show-and-tells, people often say "Of course you must use an eccentric chuck" when they ask about my work. I always have to tell them "no, I don't".

 

[Tom Gall]

If all else fails, I was gonna make a cone center, with a cone on the undertbe cone, to fit thr cone in the tool, and then use double pressure tape to secure the cone center to the off center cone on the tool in the link.

Would something like this help?

Cup Center Converter

Attaches to your live center magnetically! Converts a standard 60degree live center to a cup center. Avoids splitting, superior grip on your work at the tailstock. Installs instantly. Compatible with PSI #LCENTLT1 & #LCENTLT2

www.pennstateind.com

 

[Vincent Vogel]

You could make the goblet in three pieces. Make the cup and base then turn the pedestal separate so you aren't swinging a lot of weight and use mortise/tennon joints to join them. The live center you have linked would be good for making tapered shafts.

 

[Tom Lucas]

Would something like this help?

Cup Center Converter

Attaches to your live center magnetically! Converts a standard 60degree live center to a cup center. Avoids splitting, superior grip on your work at the tailstock. Installs instantly. Compatible with PSI #LCENTLT1 & #LCENTLT2

www.pennstateind.com

That cup center is built into the Nova live center. I use it often, especially when vacuum chucking to get a little better support without the center dimple.

 

[Bill Alston]

I mentioned this device in another thread. Perhaps it could be adapted to your use in some way? There are two 1/2” diameter holes in the face in which you might be able to mount something suitable? Just a thought.



Edit: I’ve just seen this:

 

[Bill Alston]

Then there’s this, all ready to go?

 

[Terry Brown]

The offsetting centers are for cutting "TAPERS". When you made this beautiful multi axis piece, you cut, stopped and relocated where the center touched your work. Each relocating of the center gave a new axis. The offsetting centers only shift the axis in relation to the lathe bed. You will still be using the same two centers / points in their original location on your wood. To get multi axis work between centers, you "MUST" change where the centers make contact with your wood. As you did. As earlier stated, something other than a pointed cone center would be a very good idea. Keep up the good work.

 

[Nick Valenza]

Vicmarc offers an Eccentric chuck.

Looking for the other end. TS end.

 

[Nick Valenza]

Would something like this help?

Cup Center Converter

Attaches to your live center magnetically! Converts a standard 60degree live center to a cup center. Avoids splitting, superior grip on your work at the tailstock. Installs instantly. Compatible with PSI #LCENTLT1 & #LCENTLT2

www.pennstateind.com

Maybe, but I still need to make the off-center piece.

 

[Nick Valenza]

I ended up with this. Thank you all for your suggestions and help! Off-center Tail stock Support

 

[Nick Valenza]

Then there’s this, all ready to go?

View attachment 59764

This is what I wanted, but didn't want to buy!

 

[Darryl Fective]

Looking for the other end. TS end.

Why? As Terry said above, shifting your tailstock off-center won't do much of anything on a wood lathe.

 

[Nick Valenza]

I mentioned this device in another thread. Perhaps it could be adapted to your use in some way? There are two 1/2” diameter holes in the face in which you might be able to mount something suitable? Just a thought.

View attachment 59762

Edit: I’ve just seen this:

View attachment 59763

Thanks Bill! I remember seeing the former post, but I just went with this. WIth the help from everyone herr, and John from HVally Tools (Formally MLCS)

 

[Bill Alston]

I’m glad you sorted something out Nick.

 

[Nick Valenza]

Why? As Terry said above, shifting your tailstock off-center won't do much of anything on a wood lathe.

I didn't get that from his response? Hmm. Not sure I follow your response. Supporting certain off axis pieces with a revolving off-axis TS support can help you turn certain pieces 10 fold. Lookat the weight of the cup vs the stem holding it. HS at foot side. I worked cup first and turned Down toward the foot (HS side). The further down towards the HS, the less meat supporting the cup, and the more likely the stem wound snap and send the cup flying. Getting a cone into the cup TS side and allowing to rotate on whichever axis deemed fit would prevent that.

See This social media post I made.

Times link this I wish I could just say it with my voice!!! Hahaha

 

[Nick Valenza]

The offsetting centers are for cutting "TAPERS". When you made this beautiful multi axis piece, you cut, stopped and relocated where the center touched your work. Each relocating of the center gave a new axis. The offsetting centers only shift the axis in relation to the lathe bed. You will still be using the same two centers / points in their original location on your wood. To get multi axis work between centers, you "MUST" change where the centers make contact with your wood. As you did. As earlier stated, something other than a pointed cone center would be a very good idea. Keep up the good work.

Thanks for calling Terry! It was a pleasure taking to you!

 

[Don Wattenhofer]

The offsetting centers are for cutting "TAPERS". When you made this beautiful multi axis piece, you cut, stopped and relocated where the center touched your work. Each relocating of the center gave a new axis. The offsetting centers only shift the axis in relation to the lathe bed. You will still be using the same two centers / points in their original location on your wood. To get multi axis work between centers, you "MUST" change where the centers make contact with your wood. As you did. As earlier stated, something other than a pointed cone center would be a very good idea. Keep up the good work.

Also note that the headstock drive must have flexibility to account for the miss alignment between the HS & TS centers, a fixed grip like a scroll chuck would never work.

 

[Nick Valenza]

Also note that the headstock drive must have flexibility to account for the miss alignment between the HS & TS centers, a fixed grip like a scroll chuck would never work.

I could just re-align my headstock before i start?, and why wouldn't a fixed grip scroll chuck work with the revolving TS live center I made? The cup on the TS side will be in a fixed position from center?

 

[Tom Gall]

I could just re-align my headstock before i start?, and why wouldn't a fixed grip scroll chuck work with the revolving TS live center I made? The cup on the TS side will be in a fixed position from center?

Nick, unless I'm missing something in your drawing that won't work at all. The goblet cup will be whipping around with that tilted tenon in the chuck. Your cone center (revolving or not) would be useless. The entire jig in the TS would have to rotate (not just the live center/cone) and that gizmo that you linked to doesn't appear to do that. Your 3mm offset produced good results and you could probably double that without too much of a problem. Are you looking for multi-axis with offset points or parallel points (camshaft type)?

 

[hockenbery]

could just re-align my headstock before i start

Like @Tom Gall said.

On the tailstock the end will follow a circular path. you would need a disc mounted on the tailstock where yo can attach a revolving holding. mechanism. A lot like a geostationary satellite obit that always faces the earth above the equator.
That’s a lot going on to provide support.

One way to test center alignment is to bring a tailstock with a dead center in it into contract with a smoothed surface piece of wood spinning on the head stock. If it makes a point - aligned
If the dead center point scribes a circle that is how far it is out of alignment.

 

[Rick Moreton]

If your live center has threads for a removable cone, etc. you could maybe use that to attach a circle of wood. Then screw a tennis ball or similar to the correct distance out to hold the cup.

One thing to watch out for is that with the added weight of the live center at the tailstock (for this and other solutions), it acts like a flywheel. You could snap a delicate turning as the lathe starts because the weight of the live center resists moving more than normal. Likewise, as you stop the lathe the tailstock will want to keep spinning.

 

[Don Wattenhofer]

I could just re-align my headstock before i start?, and why wouldn't a fixed grip scroll chuck work with the revolving TS live center I made? The cup on the TS side will be in a fixed position from center?

Try offsetting per your sketch then move the tailstock back and turn the piece by hand and the opposite end will make a circle, which should demonstrate why the chuck won't work. The other problem with that if you use a chuck on the tailstock end the extra weight will likely break that fragile stem.

 

[Brian Gustin]

Out of left field thought: what if you had a tennis ball mounted in jaw chuck - wrap in plastic wrap or something to reduce friction, you could have tail stock end offset on the point and cup end centered on headstock, tennis ball would allow wobble movement so TS end would be offset while cup end stayed centered? would that maybe work, sorta? I imagine it would require extremely light cuts with a very sharp gouge and absolute zero catches (In other words someone with expertise at tool control to never or almost never get a catch..)

 

[Nick Valenza]

Nick, unless I'm missing something in your drawing that won't work at all. The goblet cup will be whipping around with that tilted tenon in the chuck. Your cone center (revolving or not) would be useless. The entire jig in the TS would have to rotate (not just the live center/cone) and that gizmo that you linked to doesn't appear to do that. Your 3mm offset produced good results and you could probably double that without too much of a problem. Are you looking for multi-axis with offset points or parallel points (camshaft type)?

Well your not missing much. I am using a No3 Vicmarc chuck which does parallel (up to 30mm off set) and diagonal (15 degrees off set max). But i could do the same things with a set of 50mm(ish) jaws using only diagnal (as shown in picture). The goblet cup would be whipping around, but once i start taking the meat of, that goblet cup is gonna be whipping more around. I started turning this 3mm off at around 1600 rpm, lowering the rpm gradually to about 1200 which each axis I moved to (as the same time, more meat was being removed in the direction of the TS to the HS). I would like to keep at 1600 or higher and not have to worry about the weight of the goblet cup forcing it to become a trebuchet! haha. i just want to generally stabilize the cup, not to actually provide any horizontal support. Its good to know I could probably go 6mm off center, but i plan on doing this with other species, Walnut prioabbly being the least dense species, i figure anything less dense will snap (unless i generally support the goblet from flying out lol

 

[Nick Valenza]

Like @Tom Gall said.

On the tailstock the end will follow a circular path. you would need a disc mounted on the tailstock where yo can attach a revolving holding. mechanism. A lot like a geostationary satellite obit that always faces the earth above the equator.
That’s a lot going on to provide support.

One way to test center alignment is to bring a tailstock with a dead center in it into contract with a smoothed surface piece of wood spinning on the head stock. If it makes a point - aligned
If the dead center point scribes a circle that is how far it is out of alignment.

Please look at This social media post I made. I created this revolving tailstock end after talking with John at HValley tools (great guy) (before I got a response from here) which i haven't used yet, but i think is exactly what you are saying. i attempted to draw this in the drawing.

 

[Nick Valenza]

If your live center has threads for a removable cone, etc. you could maybe use that to attach a circle of wood. Then screw a tennis ball or similar to the correct distance out to hold the cup.

One thing to watch out for is that with the added weight of the live center at the tailstock (for this and other solutions), it acts like a flywheel. You could snap a delicate turning as the lathe starts because the weight of the live center resists moving more than normal. Likewise, as you stop the lathe the tailstock will want to keep spinning.

Is this what you are talking about? Also the Nova Orion has a computer that I can set to 'Oversized/unbalanced' which forces the motor to start and end slowy to prevent the flywheel action Let me know!

 

[Nick Valenza]

Try offsetting per your sketch then move the tailstock back and turn the piece by hand and the opposite end will make a circle, which should demonstrate why the chuck won't work. The other problem with that if you use a chuck on the tailstock end the extra weight will likely break that fragile stem.

Well I am not using a 50mmish jaws, I am using the No3 vicmarc, which has the wood jammed into the chuck with a 22mm tenon. But I will try with the 50mm jaws. I will cut the cup on center, then move it off center by say 5 degrees, Stick the revolving live center into the TS Click here if you haven't done so already. And align the offset TS revolving cone center in the goblet. NOT to apply any pressure, JUST to prevent it from becoming a trebuchet! haha

 

[Nick Valenza]

Out of left field thought: what if you had a tennis ball mounted in jaw chuck - wrap in plastic wrap or something to reduce friction, you could have tail stock end offset on the point and cup end centered on headstock, tennis ball would allow wobble movement so TS end would be offset while cup end stayed centered? would that maybe work, sorta? I imagine it would require extremely light cuts with a very sharp gouge and absolute zero catches (In other words someone with expertise at tool control to never or almost never get a catch..)

Love to see this in action! haha Thanks Brian!