One way steady

[hockenbery]

I'll be attempting to email you these pictures and script copy......but, I thought I'd show this on the forum while I'm at it! 😀

The second photograph shows the bowl steady set up for a large 14" maple burl platter that is on my lathe right now. You'll notice that I've made a modification, extending the scissor arms out a little distance. On the end of that extension, I've installed a coil spring. The tension of the spring is applied to the wheels, allowing for the wheels to have a small amount of give and take, depending on how much the bowl, or platter warps during the final shaping. (It nearly always does!) Without this modification, the wheels applied to the spinning bowl gives uneven pressure to the bowl, depending on the amount of warp there is. I've found that the spring gives the wheels a more evenly distributed pressure against the bowl as it's being turned.......a very good thing, if you know what I mean! .....and, likewise for my spring modification, because the warp in some bowls can exceed any usefulness of the Oneway bowl steady altogether......

ooc

Odie,
This maybe deserves a thread of its own. Don't want to hijack Robs thread .
Basically what you have done is let the wheels move a bit. This seems to me to be similar to the control I get by putting fingers behind the rim.
My fingers do a pretty good job of dampening the vibration.

Up to a point I feel there is a slight advantage to fingers in that the fingers to gouge maintain a constant distance so they move together on a slight warp
They fingers sort of act like calipers in a sense.


Your steady seems to have a couple of advantages. Fingers only give support for a few inches which is usually enough.
The second is woods like maple Burke with the spikes and inclusions are rough on the fingers.
Third is when working with a sharp rim you don't risk cutting your fingers.

Thanks for the tip,
I tried posting your photo here
Al

 

[Odie]

Odie,
This maybe deserves a thread of its own. Don't want to hijack Robs thread .
Basically what you have done is let the wheels move a bit. This seems to me to be similar to the control I get by putting fingers behind the rim.
My fingers do a pretty good job of dampening the vibration.

Up to a point I feel there is a slight advantage to fingers in that the fingers to gouge maintain a constant distance so they move together on a slight warp
They fingers sort of act like calipers in a sense.


Your steady seems to have a couple of advantages. Fingers only give support for a few inches which is usually enough.
The second is woods like maple Burke with the spikes and inclusions are rough on the fingers.
Third is when working with a sharp rim you don't risk cutting your fingers.

Thanks for the tip,
I tried posting your photo here
Al

Hiya Al............🙂

Yes, thank you, and you are certainly welcome. I believe you are absolutely correct that the wheels of a bowl steady are doing the same sort of thing as using your fingers to steady the workpiece. From my point of view, there is some amount of difference. The bowl steady is much more controllable, and allows you to use both hands for tool control.


Using the fingers is something I've used quite a bit, and still do on occasion. First choice would be to use a bowl steady, if that is within possibility. There are times when the shape of the bowl negates using the bowl steady, so fingers are always a final option.


No matter how much a bowl's moisture content is stabilized to the ambient atmosphere, as the wall thickness is reduced to the final thickness, there will nearly always be some degree of additional warp that occurs as a result of creating, or altering internal stresses in the wood itself. Theoretically, the bowl steady would be a perfect solution.....IF the host bowl remained a constant perfect circle, which it seldom does.....unfortunately, we woodturners don't live in that perfect world!


I have seen certain bowls that do not warp during final shaping to any detectable degree, but that is the exception to the rule. The rubber composition of the wheels used in the bowl steady have a certain amount of ability to move with the changing out of round conditions, but that can only go so far to preserve the stabilizing effect of the bowl steady. The spring allows for a little additional movement, and I find that very helpful. There comes a point with some bowls, where the warp becomes so pronounced, that a bowl steady is ineffective for it's purpose. At that point, if fingers don't do it, nothing will! 🙁


I can remember experimenting with the Oneway bowl steady when I first got it. The first tendency for me (and, I suspect.....others) is to increase the pressure of the wheels on the bowl when the steady was, or became ineffective for it's purpose. This exacerbates the problem because, in effect, what is happening is the wheels are attempting to alter the shape of the bowl back to perfect round......not good, because now you've got two separate forces that are attempting to alter the shape of the wood......the bowl steady, and your lathe tool's cutting action. The bowl steady works at peak performance with only a light wheel pressure to the bowl. The point is to avoid disrupting the shape of the bowl through the bowl steady, whether that shape be perfectly circular, or not. In other words, there comes a point where additional wheel pressure is worse than nothing at all. The spring allows the operator to increase the bowl steady's range of effectiveness, to a point. Once that point is reached, the bowl steady is no longer the best option.


Good idea about getting this on a separate thread........It was never my intention to go beyond that, but it became necessary to respond. My first post over there on Rob's thread should be clear evidence of that.


Thanks for listening, and hopefully all this makes some sense to a few of you, If so, my purpose in collecting my thoughts to compose this post won't be a total loss......🙄 As someone once mentioned on this forum; To explain what you mean, your ideas, experiences and thoughts to someone else, is to further your own level of understanding. I believe that is very much true, and one of the great benefits of participating on this forum..........not to mention that I have benefited from other points of view, over and over again! 😀


ooc

 

[hockenbery]

The bowl steady is much more controllable, and allows you to use both hands for tool control.
I find that very helpful.

ooc

I use two hands with fingers behind the rim. My thumb is on the gouge pushing behind the bevel.
This may be an element of turning style.

For push cuts, I generally have the forefinger of my forward hand under the gouge and thumb pushing behind the bevel.
So a modification to reach under a spindle with a finger or behind the rim of a bowl isn't much of a deviation.

Many bowl turners use this same cradling with the thumb and forefinger of the lead hand for their finish cuts.
Almost all spindle turners use a thumb and finger.
I think It gives a lot more control.

Al

 

[David Wilkins]

I have the same steady, I use fingers and thumb almost always. However, I had a bowl essentially explode, pieces everywhere. One piece cut me a bit, not a lot, however I did have very thick skin on my hands at the time. I have toyed around with the steady, I think you will find it more effective and out of the way if you place it on the other side of the bowl.

 

[MichaelMouse]

I have the same steady, I use fingers and thumb almost always. However, I had a bowl essentially explode, pieces everywhere. One piece cut me a bit, not a lot, however I did have very thick skin on my hands at the time. I have toyed around with the steady, I think you will find it more effective and out of the way if you place it on the other side of the bowl.

Fingers to stabilize vibration of the piece are really risky, unless you remember to round the corners of the rim. The combination, cut/burn that you get on a sharp edge is painful, though it seldom bleeds much, due to the cautery.

The reason the steady is a steady is that it doesn't give. Though other types are made with points contacting at various places, the best use of the Oneway here is to cut between the two wheels. The upper dampens any vibration coming into the tool and begins alignment, the lower, where the cut is made, keeps the piece from moving away due to changes in friction or outward pressure from the tool presentation as the cut is made.

Had to read your post twice before I realized you weren't advocating what I do with the steady when not in use. I swing it back behind the ways where it doesn't contact the work or interfere with the chuck. It's out of the way, but more to the ready than removing it to its position on the shelf.

If your piece is clattering, and you don't care that it will be unequal thickness, you can give it a tape wrap or use that stretch stuff they wrap molding bundles with at Menards (Saturday). It's handy where you have doubts about the structural integrity of the piece as well. You still want to listen for and glue any discovered cracks, but you won't get a centrifugal smack on the knuckles if you wrap the exterior. The stretch stuff is a pretty good way to reinforce if you use a jam chuck, too. Or for other light alignment/hold duties in the flatwork.

 

[Odie]

I have the same steady, I use fingers and thumb almost always. However, I had a bowl essentially explode, pieces everywhere. One piece cut me a bit, not a lot, however I did have very thick skin on my hands at the time. I have toyed around with the steady, I think you will find it more effective and out of the way if you place it on the other side of the bowl.

Hi David.......

For exterior turning, I always put the wheels on the back side of the bowl as well......out of the way of tools. For interior turning, The wheels are on the front......closest to the cutting action of the tools.

Who knows why your bowl exploded, but from my observations of how the bowl reacts to it, I suspect the pressure of the wheels against the bowl was too great. When this is the case, there are multiple forces being applied to the bowl at the same time. I don't think I've "exploded" a bowl, using the Oneway Bowl Steady, but I've cracked one or two this way. After observing what happens initially, one learns to back off the wheel pressure, instead of increasing it. The reasons are two fold.......tools respond better, and there's much less stress on the bowl.

ooc

 

[Odie]

Though other types are made with points contacting at various places, the best use of the Oneway here is to cut between the two wheels. The upper dampens any vibration coming into the tool and begins alignment, the lower, where the cut is made, keeps the piece from moving away due to changes in friction or outward pressure from the tool presentation as the cut is made.

Hello MM........

As mentioned in my above post, when doing exterior turning, the Oneway BS is placed on the back side. For this particular application, it's not possible to have the wheels on both sides of the cut (one above and one below).......but, I believe it would be a bit better overall, if it were. As it is, placing the wheels on the back side is much better for tool usage, as it is out of the way.

What is actually happening between the wheels is theory, on both yours and my part, but I suspect your conclusions of what is happening with the upper wheel is a good guess.....and would be my guess, too. As for the bottom wheel, I have a mental picture of a "wake" like vibration coming off the tool and passing through the wood below the tool.......the bottom wheel serves to stabilize that. The "wake" would be similar to that you'd observe behind a boat moving through the water.........

I guess the only way to know for sure how the vibration patterns originate and are dampened would be to make a scientific study of it with some way to measure the location and intensity of the vibrations. It doesn't really matter what those vibration's physical properties are, really.......what matters is whether the bowl steady serves to reduce them, and how well this benefits any individual turner.......right? From my point of view, the bowl steady works well enough that I really couldn't live without it! It does have some limitations, so it's not a do-everything device for any-one's needs. I suppose it would be fair to give Al his due on this, and state that, for his particular purposes, fingers do a better job than the bowl steady......😀

ooc

 

[Bill Boehme]

While we're throwing around theories, I'll toss one in the pot. The biggest vibration problem occurs when there is a spatial resonance because that is when the amplitude of vibration is the greatest. A resonance is a standing wave on the surface of the turning which will have nulls and peaks. A spatial resonance is one that is a function of distance and not time. A null is where the deflection is zero and the peak is where the deflection reaches its maximum value. If we had a strobe to "freeze" the position of the turning we could actually see where the peaks and nulls exist and measure the distance between them. We don't have a strobe to actually do this, but we can make an assumption that there will be an even number of peaks and an even number of nulls. These multiples of two are called harmonics. This might not be the case for super thin green turnings that are behaving more like a wet dish rag or a turning that has large voids or flaws such a cracks, but it would apply for most other turnings. Knowing this, we could use something like the Oneway steady rest to make contact at two points that are not equal to the distance between two nulls or between two peaks. The ideal distance would be equal to the distance between a null and a peak. Given the even harmonic behavior of resonances we could further assume that placing the two wheels of the steady rest at approximately 90° points on the circumference of the turning would dampen the second harmonic. If there is a higher order harmonic then perhaps 45° spacing would give better results. A happy medium of about 60° might adequately take care of either situation.

This is an oversimplified description because resonances are often a function of both time and geometry. Otherwise we would see my spatial frequency argument run into an obvious problem at zero speed. Before a turning gets very thin and flexible, time based resonances can be controlled by changing the speed of the lathe. At some point when the turning is thin enough to be somewhat flexible the benefit of changing the spindle speed diminishes as spatial resonance becomes dominant.

Anyway, that's my theory and that along with $5 will get me a cup of coffee at Starbucks (if I drank coffee, which I don't).

 

[MichaelMouse]

If you use the wheels away from the tool, you are merely using as a damper, spring or no spring. Further, you are dampening where no work is done. The real spring comes from the wood. Can't see what effect that support across the axis of rotation from the tool will have, since the piece will flex freely with nothing to steady it where the tool contacts if there's nothing on the outside of the wood where the tool's cutting in. That's where you bold people put the hand, right? Not across the bowl.

Which is why the steady is used where the tool is used, and for the reasons outlined. It is to prevent deflection due to the tool. You want the wheels pretty close to prevent the tool from inducing vibration. Shorter strings have less amplitude available. They also require what the steady prevents, the initial twang. See how things change with an actual string as you run the frets. The wood is your string.

Of course, there are still those who say that the 1/2" steel bar hanging 3" over the rest is the source of chatter rather than the 1/4" thick wood on the rim, which is supported (somewhat) six-eight inches away. I guess it's just "theory" to them, and not strength of materials....

 

[robo hippy]

I have never used a steady rest. The biggest problem with vibrations seems to be more from too much 'rubbing the bevel'. If finger pressure = bevel pressure, and that being very light, it is possible to get a smooth cut. Platters do seem to want to vibrate more than bowls for some reason, and on them, it is more important to leave mass in the center, and nibble your way down inside. For some reason, I do find it possible, on most bowls, even up to 16 inch diameter to come back to the top rim and make a final pass all the way to the bottom.

robo hippy

 

[Bill Boehme]

....... For exterior turning, I always put the wheels on the back side of the bowl as well......out of the way of tools. ......

Why would a steady rest be needed at all for turning the exterior given that the interior has not been turned yet or that the wall thickness is still substantial?

..... I suspect the pressure of the wheels against the bowl was too great. When this is the case, there are multiple forces being applied to the bowl at the same time. I don't think I've "exploded" a bowl, using the Oneway Bowl Steady, but I've cracked one or two this way. After observing what happens initially, one learns to back off the wheel pressure, instead of increasing it.
......

Because I am frugal, I use the finger method for damping vibrations, but only for nice smooth surfaces. I have already "felt" of a natural edge with the turning spinning and concluded that I ought not be doing that.

My understanding of steady rests along with thinking about what the wheels should and shouldn't be doing tells me that the steady rest ought not be applying any more than finger pressure to the wood. Otherwise the wheels would be contributing to the problem that they are intended to reduce. What is the difference between applying pressure from the wheels and applying gouge pressure if they are both significant enough to cause a deflection as the wood spins? Or from the wood's perspective, how does it know who or what is pressing on it? All that is knows is that something or somebody is pushing it and the wood is going to howl about being pushed around.

 

[Odie]

Why would a steady rest be needed at all for turning the exterior given that the interior has not been turned yet or that the wall thickness is still substantial?

The answer is really very simple...... It's because a finer surface quality is possible with the dampening effect of the wheels......true for thinner walls, but also true for walls of substantial thickness. I've found this to be the case for interior, as most would probably agree.....but, it is also true for exterior finish work, even with the wheels on the backside. As I stated previously, the bowl steady would undoubtedly work even better, if the wheels were positioned in the front, straddling the tool......but, the problem with that is it's an obstruction for tool usage. In the case of exterior turning, it's a trade-off, but the benefits are worth using the BS on the back side, even if it's not the most effective use of the wheels. By the way, using the wheels on the backside isn't my idea......that was a tip offered by someone else at another time. The spring is my idea.

One can theorize and speculate forever about these things, but the real evidence is with practical application. (That statement shouldn't be necessary, but obviously some people rely on theory and speculation more than "hands on" application!)

Over and over again, I've been working on a bowl without the bowl steady, and after installing it, got a better finer finish cut.......same bowl, same tool, same time, same everything, except with the addition of the bowl steady. Now, this is not to infer that a better cut is possible each and every time the bowl steady comes into play, but it happens often enough that the benefits are well worth using one to see if there is improvement.

Bill......true, one can get a very good cut with a minimum of sanding required, without using a bowl steady. If that's satisfactory for you, MM, Al, or anyone else who is following this thread......fine with me. I could care less what anyone else chooses to do.......all I'm doing is offering something that has demonstrated a positive result in MY turning. I suspect a few other turners will benefit from what I've learned.....and that's why I'm offering up for others to use......or not use!

ooc

 

[Bill Boehme]

Odie, I'm sorry that my post was interpreted as a hostile response to you. I only intended to toss in my two cents worth. I certainly don't have any dislike for using a steady rest. I am actually in the market for a large HF steady rest. I don't know what I will wind up with. I like several of them such as the Sinner and Robust models, but I might just wind up making my own.

I do not think that I have a problem with surface smoothness, but my approach is to use a very light touch with the gouge and turn slow. It might also be that the wood I turn doesn't move very much.

 

[Odie]

Odie, I'm sorry that my post was interpreted as a hostile response to you. I only intended to toss in my two cents worth. I certainly don't have any dislike for using a steady rest. I am actually in the market for a large HF steady rest. I don't know what I will wind up with. I like several of them such as the Sinner and Robust models, but I might just wind up making my own.

I do not think that I have a problem with surface smoothness, but my approach is to use a very light touch with the gouge and turn slow. It might also be that the wood I turn doesn't move very much.

Not interpreted as hostile, Bill.........just responding to content, as I see it applies. 😀

I apologize for my strong wording.......I was feeling a bit frustrated with some of the replies.

You, in the past, have been very helpful......and, have caused me to alter my course a few times! I am a better turner for those times you and others have given me bits and pieces of what makes my puzzle fit......if that makes any sense.......😕😀



ooc

 

[Odie]

Oh, BTW, Bill.........

There was a very excellent thread several years ago where some very creative home built full circumference bowl steadies were shown by other participants in the forum......you might want to check on it, but it might be long enough ago that it dropped off the edge of the earth!

I believe it was that thread that caused me to order my "spin doctor" (Clark steady rest, advertised in the AAW magazine) with nine positions and five wheels. The jury is still out on whether that was all worth while, or not.....but, it was a special order on my part! Most of these rests have three wheels and three positions.

ooc

 

[Grant Wilkinson]

I must start my post by stating that you can count the number of bowls I've turned on 20 fingers and toes. That includes those that I've tossed. No expert here.

I don't have a steady yet, but have been looking, as I used one frequently on long spindles.

Would it be fair to say that the ideal steady, when turning on the outside of a bowl would be applying pressure equal to that from the gouge, from the inside of the bowl? I'm not saying that such an animal is possible, only that I see steadies being used on the outside of a bowl to counter the gouge pressure when turning the inside of the bowl. So, I'm putting it out there to be shot down that the opposite would be true, too.

 

[hockenbery]

I must start my post by stating that you can count the number of bowls I've turned on 20 fingers and toes. That includes those that I've tossed. No expert here.

I don't have a steady yet, but have been looking, as I used one frequently on long spindles.

Would it be fair to say that the ideal steady, when turning on the outside of a bowl would be applying pressure equal to that from the gouge, from the inside of the bowl? I'm not saying that such an animal is possible, only that I see steadies being used on the outside of a bowl to counter the gouge pressure when turning the inside of the bowl. So, I'm putting it out there to be shot down that the opposite would be true, too.

Hi grant
This is not a shoot down... A common mistake we all make starting Out is to press too hard on the bevel to keep it in contact.

In the ideal cut you apply no pressure toward the bevel which rides on the surface you are cutting and would at some point be opposite the steady.
As mere mortals the best we can achieve is minimal pressure.
The pressure and consequent bevel drag sets up a vibration in the bowl. A steady should dampen the vibration.
A smaller gouge or grinding off the heel of the bevel reduce bevel drag. By having less bevel to make contact.

Now you are exactly right. the gouge should put no pressure on the bowl and the steady should put no pressure on the bowl. 0=0 so the pressures are the same.

Generally unless you are doing large thin rimmed bowls or platters a steady is not needed.

A 12" bowl with a 1/2" wall thickness should OT require a steady. 1/8"wall thickness might need a steady. But lots of folks go this thin without a steady.

Al

 

[MichaelMouse]

There are those who press outward quite a bit when removing the inside. They want to "ride" because they read some(every?)where that was the way to steady a cut. As Al says, that's really not what you should be doing. I think the majority of experienced turners have been there and are done with that part of the problem, even if they continue to use the misleading term "ride" versus "guide". You may soon find the tool moving fore and aft to try and follow a non-circular surface if you ride. Underhand grips are, I believe one of the ways we can exacerbate this. Fingers don't have the strength to keep things properly aligned as swinging the arm or body around a firm fulcrum does. So ride the rest, guide the turning.

I think most of the induced vibration on thin pieces comes from the unequal friction on the tool as it slides from down grain cutting into up grain. Newton being who he is, when you develop more friction pushing down to cut up grain, the body of the turning recoils (Law 3) and tries to climb. The upper wheel which dampens outward motion is literally on top of this reaction as I place my gouge. If it is not allowed to recoil, we get all power to the cut, not to transfer of momentum. One of the reasons I favor the broad sweep gouges is because they can shave with minimum shear across the nose. The less shear, the less "lift" generated into up grain cuts. Note that the shear angle I'm referring to is not perpendicular to the surface of the piece, as in "shear scraping," but perpendicular to the advance of the tool. When the tool is advanced with skew as well, it further reduces this drag, just as skewing any other edge when cutting/carving wood does. Listen to the sound in this clip and note with your eye how it correlates with the break in the shaving being thrown across the frame. That's up grain/down grain differential. As it starts to cut up, the shaving breaks. http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=CherryPeelIn.mp4 As the curve flattens, the noise changes.

One other thing to note in the clip is that the shavings do not rise much at all. No lift left as the edge comes out of the cut makes for no recoil and, since those two up grain areas people always complain about tearing are not being lifted and torn - makes for much less sanding.

I will say that if you have a steady, you should use it at ~1/4" even if you don't really need it. There are those days, those honings and those pieces of wood that will forgive, and then there are those which might not, where you take out insurance.

Not all outward pressure is bevel riding. If you consider the slope of the sides, you'll have a vector cross as you advance, as well as a vector parallel. That's why you are normally swinging the handle of the gouge outward as you proceed, to minimize that vector.

 

[Grant Wilkinson]

Thanks to you both. I certainly didn't take anything said as a put down.

I don't believe that I'm putting much pressure on the gouge. I don't have a steady yet, but have done a few things that might have benefited from having one. Even light pressure on thin walls - 1/8" - sets up some flexing, I find. I've been turning wet to final wall thickness and getting some nice warped shapes, but the walls need to be thin, I've found, to keep them from cracking. I think a steady would help me to get consistent wall thickness from the rim to the bottom. Right now, I'm using silly string to add some rigidity when I'm doing the inside.

I've also been doing open segmented pieces lately, and they sing out well if I push a bit too hard.

 

[Odie]

I must start my post by stating that you can count the number of bowls I've turned on 20 fingers and toes. That includes those that I've tossed. No expert here.

I don't have a steady yet, but have been looking, as I used one frequently on long spindles.

Would it be fair to say that the ideal steady, when turning on the outside of a bowl would be applying pressure equal to that from the gouge, from the inside of the bowl? I'm not saying that such an animal is possible, only that I see steadies being used on the outside of a bowl to counter the gouge pressure when turning the inside of the bowl. So, I'm putting it out there to be shot down that the opposite would be true, too.

Grant......

I believe you are right. I've thought the same thing about applying equal wheel pressure on the inside of the bowl when doing the exterior. To my knowledge, such a steady is not being produced, and I'm not sure how one would go about designing such a critter. It's not totally out of the question, though, because if the desire to have one was great enough, I'm sure someone could, and would come up with a viable design to accomplish this configuration.

One good rule about positioning the wheels, is to have them axially in line with the axis of the lathe......that is, the wheels themselves work best when running 90 degrees to the rotational axis of the lathe (axis of the wheel itself would be parallel to the axis of the spindle). This can be fudged a little bit, but unless the bowl rotates perfectly in line with the wheels, they will necessarily "skid" because the wheels are designed to roll a straight line, and something has to give if the path of the bowl presented to the wheels is not running true to the direction the wheels are aligned. I see it's now changed, but the old promotional photo of the Oneway bowl steady on the CSUSA site had the wheels running axially perpendicular to the lathe axis.......this won't work well at all.

ooc

 

[Bill Boehme]

Grant, it probably has already been stated, but when turning wood, it is going to go oval to some extent especially if it is green. This means that the gouge pressure, no matter how light, is going to vary. The same thing goes for a steady rest making contact with an oval surface. Ideally, we would like for the force that the tool edge exerts on the wood to be purely tangent to the surface, but there will always be a bit of radial force. Things get most interesting when the wood gets thin enough to not only go oval from relieving internal stresses, but also vibrate due to the cutting force on wood that is no longer very stiff.

 

[MichaelMouse]

I don't believe that I'm putting much pressure on the gouge. I don't have a steady yet, but have done a few things that might have benefited from having one. Even light pressure on thin walls - 1/8" - sets up some flexing, I find. I've been turning wet to final wall thickness and getting some nice warped shapes, but the walls need to be thin, I've found, to keep them from cracking. I think a steady would help me to get consistent wall thickness from the rim to the bottom. Right now, I'm using silly string to add some rigidity when I'm doing the inside.

Wet wood is going to shrink after, and will definitely flop a bit when turning at 1/8. Cured wood is another matter. As to consistent wall thickness, it won't be too noticeable, but you'll be about 5-7% thinner on the long grain than on endgrain after you're cured with most woods. As far as curing thin, I've found that most all domestics will survive normal drying without self-destruction at 3/8 or below. How far below is aesthetics, not technology.

I don't turn any but small aperture stuff and irregular edge pieces, where the use of a steady would be difficult, wet to final. I rely on the minimum uplift technique to cut down on squirm with them, though I recall some full branch spalted ash and beech that would deflect a quarter inch or more at the rim when wet. Was like turning jell-lo.

As far as inside "steadies" go, if you're turning outside/inside/outside inside in search of your aesthetic, you might try a method advocated a number of years ago by some big-name Kiwi turner. Put a circular disk inside the piece and pull up the tailstock. Sort of like a reverse jam chuck. Don't bother trying to control distortion by leaving the disk in, or going to a cross-grain brace to avoid shrink on thicker stock as he advocated. Never lost so high a percentage of pieces - ever - as then.