# Bowl turning question.



## The100road (Oct 26, 2017)

ive came across this problem a couple times and I figure that I have to be doing something wrong because I never see this in the YouTube videos I’ve watched. 

I use a face plate to mount my bowl blank on the lathe. I then turn the outside of the bowl. I turn the foot and make it all nice and pretty with a recessed tendon. 

I then take the face plate off and expand my jaws into the tennon to turn the inside of the bowl. 

The bowl blank is never true once I do this. Which means I have to retrue the outside of the bowl but I can’t really retrue the foot of the bowl with some of the designs. 

All the videos I watch online put the bowl blank on the jaws and are good to go. They never have to retrue the outside of the bowl. 

What am I doing wrong?


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## Smitty (Oct 26, 2017)

I have the same thing going on. I did read somewhere that it is normal for this to occur any time one re-chucks something. I would like to be able to avoid having to re-true the outside of the bowl after I put it in the tennon as you described. Hopefully someone will have an answer for us.

Reactions: Like 1


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## The100road (Oct 26, 2017)

Being off seems to make sense to me once it’s rechucked. But then how do I retrue the foot? I never see anyone do this.


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## Smitty (Oct 26, 2017)

When you say "retrue the foot", are you referring to the bottom of the bowl surrounding the recess?


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## The100road (Oct 26, 2017)

Smitty said:


> When you say "retrue the foot", are you referring to the bottom of the bowl surrounding the recess?



Yeah, depending on the shape of the foot (sometimes tapered inwards) the tools can’t get in the tight areas to retrue the foot once the jaws are expanded. Not enough space between the wood and the chuck. 

I’ll try to take a picture tomorrow of the one I’m working on. It has a wide foot print.


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## Nubsnstubs (Oct 26, 2017)

The youtube videos probably don't show any adjustments as that would show that these turners making the videos aren't perfect. It's not a good idea to show any problems that occur when highlighting a turners prowess. 

Since I don't do recesses, I can only guess at what problems might occur. In a case of having that problem previously, I would turn the OD of my form until it's balanced and very close to the shape desired, and turn it around for hollowing. Then, I would true it up as close to the foot as possible, hollow it, sand it, and then reverse it again to clean up the foot area. That is probably how I do about 99% of all my turnings but I use a tenon instead of a recess. I also use my Tail Stock Steady 100% of the time for cleaning and truing up any imperfections on the bottom or foot. It might sound tedious, but that's how it's done in my shop....... Jerry (in Tucson)

Reactions: Like 2


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## Mike Mills (Oct 27, 2017)

Most of the time I use a recess and almost always have to re-true the exterior. This is normally very little and done with a sheer scrape with a bowl gouge or bowl skew. I don't worry about reshaping the area close to the foot because that will be taken care of at the last turning using a friction drive.

I follow my makers suggestion of at least an inch of wood surrounding the recess. In some cases I leave the outside diameter and hollow the center; in other cases I remove most of the exterior wood and only leave a small re-shaped base just large enough to remove the dovetail marks.

Stuart Batty has some very good fundamental videos on Vimeo. There are three on chucks, tenons, and recesses (about 12 minutes each).
https://vimeo.com/woodturning/videos/sort:alphabetical/format:thumbnail

Are you sure your chuck is running true? Jaws installed properly?


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## duncsuss (Oct 27, 2017)

I can think of three possible explanations:

1) your chuck is not properly configured
2) your faceplate is bad
3) you didn't cut the recess with a perfectly flat face (where the front of the jaws press against)

If you reverse the blank onto the chuck before you remove the faceplate you should be able to turn the lathe by hand and see if it's running true -- you could even bring up the tailstock with a 60 degree live center in it and use that to hold the faceplate centered as you tighten up the chuck.

Reactions: Agree 2


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## kweinert (Oct 27, 2017)

Just curious what kind of bowl blanks you use.

I see this a lot although I don't normally use a faceplate (I use a worm screw.) My theory is that if the part of the blank that's bearing on the mount (faceplate or worm screw) isn't exactly parallel to the bottom of the bowl that once you turn it around the bowl will need to be trued to the extent of the faces being out of parallel.

At least for my bowl blanks they tend to be somewhat rough cut (or at least aren't precision machined :) so any little bit of being off will result in a difference when you flip the bowl.

Or maybe I'm wrong - who knows?

It is, however, one of the reasons that I'll be making a donut or vacuum chuck (have the parts for both) so that the bottom of the bowl can be refined once the inside is complete.


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## The100road (Oct 27, 2017)

Thanks everyone. I’m pretty sure the chuck is running true and jaws installed properly. 

It’s not off a lot. Like mentioned above it is just cleaning it up with a shear scrape but that still messes up the foot. 

Recentering it with the 60 degree live center while I tighten the chuck is a good idea. I will try that next time. Thanks @duncsuss 

Does everyone have a vacuum chuck? Once I hollow out the bowl I’m not sure how I can flip it over to clean up the foot and get it centered.


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## Mike Mills (Oct 27, 2017)

It sounds like you are trying to completely finish the bottom before turning the inside where I think most folks finish the bottom last. 
From the first turning when green there is a dimple from the tailstock and that is the last thing to go after drying and returning.
A friction drive is simple. On most items an appropriate size drive held in the chuck works fine. I try to match the drive diameter to the base size so that the clean-up cut will be supported. The drive should be flat or slightly concave so that it seats around the edge. Depending on your lathe and the depth of the bowl you may need a longer friction drive; most of the time a 3/4" thick works fine for me. I can reshape the foot as wanted leaving no more than a 1/8" nub to sand away.
Your choice of friction material; leather, router pad, mouse pad, thingies from the kitchen for removing jar lids, ,,, many more. I have never lost a turning from a friction drive.

Reactions: Thank You! 1


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## woodman6415 (Oct 27, 2017)

The100road said:


> Thanks everyone. I’m pretty sure the chuck is running true and jaws installed properly.
> 
> It’s not off a lot. Like mentioned above it is just cleaning it up with a shear scrape but that still messes up the foot.
> 
> ...



I use the one way vacuum system ... when I make my recess or tenon I mark a center and put a small hole ... then use the 60deg revolving center in tail stock to center ... I mounted my vacuum release valve on wall very close to lathe so I can close it to hold with one hand .. holding the bowl center with the other ..

Reactions: Like 1


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## Nubsnstubs (Oct 27, 2017)

The100road said:


> Thanks everyone. I’m pretty sure the chuck is running true and jaws installed properly.
> 
> It’s not off a lot. Like mentioned above it is just cleaning it up with a shear scrape but that still messes up the foot.
> 
> ...




No, not everyone has them. There are too many methods for removing tenons or cleaning up bottoms where a vac wouldn't work. Also, some woods won't let a vac achieve the vacuum required to keep it secured. I'm biased here, but go to my website listed after my signature, and check out one of the tools that absolutely secures your piece while removing the tenon or nub while also allowing you to dress up the bottom* between* centers. It can't get any safer than that.

Something else not mentioned. Your piece might possibly be getting some warp between the start of turning to the time you reverse it. ............ Jerry (in Tucson)


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## Tom Smart (Oct 27, 2017)

This reverse chuck adapter is a real handy item for maintaining alignment when you turn a bowl around. 

https://www.woodturnerscatalog.com/p/112/4287/TMI-Reverse-Chucking-Alignment-Adapter

Reactions: Like 1


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## kweinert (Oct 27, 2017)

I have one of these https://www.pennstateind.com/store/LTCA18.html which would be useful for this purpose as well as others.

For example, I have some one-handed pepper mills where you have to turn a hollow body. I cut a couple of oak blocks, threaded the back side and cut the front side to fit. So I can drill out the blank, mount it between the two blocks, and turn it down without any issues.





(oops - guess I should have taken the smooshed spider off before I took the picture. Or at least turned it away from the camera.)













I have both the inside diameter (to hold the piece) and the outside diameter in the blocks. Yes, I got this one too thin. And yes, next time I turn one of these I'll turn the plug part so it's a bit longer and return the final diameter part.

This was a hybrid post. I started typing it on my PC and then went to take pictures on my phone. Navigated to the thread so I wouldn't lose my place and saw the saved draft so I just added the pictures from my phone without saving the post on the computer.

Reactions: Way Cool 1


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## Mike Mills (Oct 27, 2017)

This is one video of what most folks call a friction chuck. In his case it is mounted to a faceplate; for mine I just cut a recess for my chuck jaws and mount it in the chuck.

His does work fine but I find two problems. First, the supporting edge is a long way from where you are cutting. ie for a 12" bowl you may have a 4" base. I want the support close to the base diameter to prevent vibration. Second, you can't use that with a natural edge. If the bowl covers the chuck and friction plate it doesn't matter if the rim is flat or not.





Here is another on somewhat different.





This one shows about what I do. I do have the friction material on a wood plate, not just over the jaws. Just a few plates made up covers almost 100% of what I may need. The small natural edge bowl in this video could not be used with the large flat friction plate in the first.

Reactions: Useful 2


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## The100road (Oct 27, 2017)

@Mike Mills thank you for those videos. I have not tried the friction surface yet. I will give it a try this weekend and report back how it goes. Thank you.


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## duncsuss (Oct 27, 2017)

The100road said:


> @Mike Mills thank you for those videos. I have not tried the friction surface yet. I will give it a try this weekend and report back how it goes. Thank you.



There is one thing about using a friction surface that's worth repeating: you use a live center in the tailstock to apply some pressure (unless you have one of Jerry's Tailstock Supports) that keeps the bowl pressed against the driving system.

Just don't apply too much pressure, or you'll poke the live center through the bottom of your bowl.

(And no, you don't need to ask me how I know this.)

Reactions: Thank You! 1


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## Karl_TN (Oct 27, 2017)

@The100road , I'm still trying to figure this out myself, but here's two solutions that you might consider.

1) Reverse bowls with the faceplate attached using a "Live Tail Stock Adapter" from PSI (1 in. x 8tpi - #2MT Shaft) for $34.95. 

https://www.pennstateind.com/store/LTCA18.html​https://www.pennstateind.com/store/LTCA18.html
Note: You might need to buy a spindle adapter if your chuck has larger threads (1 1/4" vice 1"), but for some reason PSI doesn't carry a 1" female to 1 1/4" male adapter. ChucksPlus has it listed, but says they're out of stock. I'm unsure why this simple adapter is hard to find so please let me know if find any.​

2) A slightly cheaper solution is the "TMI Reverse Chucking Alignment Adapter" from Craft Supply for $29.95. They carry both a 1" or 1 1/4" part, but it's a temporary solution since it has no bearings. Accidentally leaving this on after reversing a turning might be asking for some serious trouble. 

https://www.woodturnerscatalog.com/p/112/4287/TMI-Reverse-Chucking-Alignment-Adapter​

Personally, I like one from PSI more because it has other uses as a live center when used with scraps of wood and a 1 inch x 8TPI tap. For instance, making a live center with multiple slots to support off-axis turning, or making live cup centers for turning different size balls. I just need to find an adapter to 1 1/4 8TPI. 

-Karl

Reactions: Like 1


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## DKMD (Oct 27, 2017)

It’s pretty normal to experience some runout or wobble when reversing a piece. Even with a vacuum chuck, it happens. 

I may be wrong, but I read your question differently... it seems like you’re talking about the wobble when going from faceplate to the chuck rather than reversing to re-turn the bottom after finishing the inside.

I use a tenon instead of a recess for most things, but it doesn’t change the runout. If your recess or tenon was is cut precisely with a diameter that matches your chuck jaws, that will minimize the wobble. Make sure that the surface that rests against the top of the jaws is completely flat, and make sure the angle of the dovetail matches(if you’re using dovetail jaws). Even with all of that, hollowing the inside of the bowl will often allow the shape to change a little. Also, wet wood dries somewhat while turning which can lead to wobble while scooping out the inside.

Reactions: Like 2


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## kweinert (Oct 27, 2017)

@Karl_TN 

https://www.woodturnerscatalog.com/p/112/5837/Turners-Select-Spindle-Adapter shows one from 1" x 8 TPI to 1 1/4" x 8 TPI, $21.95, 5+ in stock.

I *think* I got the directions correct - but if not the other way is showing out of stock but stocked on Nov 24th.


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## duncsuss (Oct 27, 2017)

Karl_TN said:


> ... here's two solutions that you might consider ...



A third option: the Nova Live Center System uses interchangeable ends in the live center -- one available option is a 1 1/4" x 8tpi chuck mounting accessory. The whole thing works out expensive if you don't already own the live center system.


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## Karl_TN (Oct 27, 2017)

Dupe post. Moderators please delete.


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## Karl_TN (Oct 27, 2017)

@kweinert 
Thanks for the link. The adapter you first listed appears to be the correct one based on the pic. 

Nonetheless, I still don't understand why other vendors like PSI only carry the adapter in the other direction. Seems like there would be a big need for turners having different size lathes (1 " and 1 1/4" spindles). Just put this adapter on the smaller lathe and keep everything at 1 1/4". Maybe PSI is afraid of people mounting anything larger than 1" because the bearings in the live center aren't that good.


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## duncsuss (Oct 27, 2017)

Karl_TN said:


> Nonetheless, I still don't understand why other vendors like PSI only carry the adapter in the other direction.


I suspect it's because PSI chucks are 1" x 8tpi -- they want every lathe to adapt to the chucks they sell and aren't interested in helping you use your 1 1/4" chucks.

Reactions: Agree 2


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## Mike Mills (Oct 27, 2017)

The100road said:


> @Mike Mills thank you for those videos. I have not tried the friction surface yet. I will give it a try this weekend and report back how it goes. Thank you.


One of the videos showed a very thick friction drive (IMHO), What you want is drive. A 1/2" thick means you have to compress it a lot to prevent slippage. One professional - (at least good enough that folks buys his videos) suggested Naughyde. I tried to bag one but they are elusive as Snipes.
Finally saw a recliner by the road side. Back and sides unused of course... and have a lifetime supply. 
You want thin with a lot of drive. If you have to compress 1/2" then you may have failure as described by others as breaking the bottom due to to the pressure you have to apply. 
Just guessing, but 2-3 lbs of pressure should be enough. If it slips and keeps slipping then you probably have the wrong material. Some of the best to me are the rubber jar openers (SP?). The Dollar Tree are *rap for this purpose.... other at at 3 for #2.99 are very good. Maybe 1/32 thick and lots of non-slip friction.

Reactions: Like 1 | Thank You! 1 | Agree 1


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## The100road (Oct 28, 2017)

Here was the bowl in question. This one ended up working out but I’m sure I’ll use some of the above recommendations in the future.

Reactions: Like 3 | EyeCandy! 4 | Way Cool 1


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## The100road (Oct 28, 2017)

Oh yeah, mesquite from @Az Turnings I think this was the first piece of wood I bought from WB


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## Az Turnings (Oct 28, 2017)

The100road said:


> Oh yeah, mesquite from @Az Turnings I think this was the first piece of wood I bought from WB


Amazing figure! I like the design of the bowl too!


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## rocky1 (Oct 28, 2017)

Sweet turn Stan! Very nicely done!!

Reactions: Thank You! 1


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## Robert Baccus (Oct 31, 2017)

For a friction drive to reverse the bowl to finish the bottom try this. Buy a 12" long 1/2" ID pipe at Lowe's. Attach a 3" piece of scrap to the end, turn true and pad with foam and masking tape. Insert the pipe into the small jaws of your chuck. No jaws really--the plate your real jaws attach to. We forget the small hole in the chuck body gives us a second very small set of jaws that hold metal very straight and well. Put your bowl on the padded friction chuck and bring up the cone/tailstock to finish the bottom

Reactions: Like 1


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## The100road (Oct 31, 2017)

Robert Baccus said:


> For a friction drive to reverse the bowl to finish the bottom try this. Buy a 12" long 1/2" ID pipe at Lowe's. Attach a 3" piece of scrap to the end, turn true and pad with foam and masking tape. Insert the pipe into the small jaws of your chuck. No jaws really--the plate your real jaws attach to. We forget the small hole in the chuck body gives us a second very small set of jaws that hold metal very straight and well. Put your bowl on the padded friction chuck and bring up the cone/tailstock to finish the bottom



Thanks Robert. Do you have a picture of the one you have made?


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