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Learning Curve help

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0669B3C7-F28A-48C9-94C9-EA4745DBBE75.jpeg I've now got about 10 bowls under my belt, some are just roughed and drying, others were turned to final thickness and are drying. The main wood has been maple and cherry from my yard, green. Thought it was high time to see if I can make more progress. I've searched and read many of the threads here on the topics where I've wanted help, as well as watched many you tube videos by various turners (Stuart Batty, Robohippy, Brian Havens, Wyoming Woodturner, etc.) I've been able to learn and make progress emulating some of their approaches.

There are two main questions I have, and they may be related to one another so I'll put them both here.

One involves the set up of my lathe, and stalling, the other is a bouncing tool.

Bear with me through some background.

My lathe is a Rockwell Delta 12" gap bed lathe, circa 1972, Power is a 3ph .75 hp motor with a Teco 510 VFD. The lathe has a reeves drive - the cable version. Speeds go from about 350 to 3000 or so through the Reeves, and with the VFD, can go down to nothing. Upon receiving the lathe, I dismantled it, replaced bearing in head stock, tail stock, and I think the reeves drive as well.

I'm finding that I can stall the lathe pretty easily when first roughing a bowl blank. Mounting the wood so that the ends at the tailstock and headstock are side grain. As I make my first cuts across the blank, from tailstock to headstock, it seems to stall occasionally. FWIW, much more frequently on the headstock end. When this happens, I can see the wheel on the left side of the headstock is stopped, telling me the slippage is underneath, with the belts. Might this be caused by insufficient belt tension? When I got the machine, I don't know the belts were correct for it.

Second related question, when roughing across the blank, as well as when evening out the face grain on the tailstock end, I'm constantly fighting the bounce/chatter. Just can't seem to get a smooth flow. It feels like I'm fighting the cut, and I'm definitely using more pressure than is described in the various videos, where they are able to easily and smoothly make this cut. I've tried a number of ways of rotating the tool, as well as the angle of the handle, trying to follow the bevel. This bouncing occurs with both push cuts and scraping cuts. At this point, I've got past it my using the tip more and taking much smaller bites. The only obvious difference is that I'm using a 3/8" bowl gouge, while most seem to want a half inch - measured across the flutes, not the shaft diameter. I'm not adverse to buying more tools, but at same time, figure that if I can't make the cut with the gouge I have, just getting a bigger chisel means I can't make the cut with it either.

Obviously seeing something in person would be ideal, but given circumstances, that will have to wait.

Thanks
 
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hockenbery

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I use an Ellsworth grind on my gouges. Roughing is hard to learn on your own so you are progressing quite well realizing a problem.
i prefer the 1/2” gouge (5/8 diameter bar) a 3/8 gouge (1/2” dia bar) will work fine just takes smaller cuts.

1. Cut toward the headstock. Take off the corner first to establish a smooth spot then cut from smooth to rough so that the bevel has a place to float over. Before getting into the interupted cut.

Below is a video of a technique I learned from Christian Burchard. It is an A FRAME CUT. Forward arm is straight. End of the handle is at the top of the thigh. With this grip the tool, forward arm, and torso form a rigid triangle. Slow rotate the body to move the tip of the tool in an arc - the rigid triangle keep the tip from moving forward when cutting air allowing the cut to ride the bevel smoothly through the interrupted cut.

This method anchors the tool on the tool test and keeps the tool from bouncing. It is really effective and I get a really smooth cut on the interrupted surface. When I just cut one or two spots on the corner of a blank they are smooth and no bounce.

This is a video clip from a demo showing that cut.
Cove Ruffing cut
View: https://www.youtube.com/watch?v=EIHADKjfL2c

This is the demo of rough turning the whole bowl.
Roughing green bowl -
View: https://www.youtube.com/watch?v=Lo0bGSafZq4
 
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hockenbery

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One involves the set up of my lathe, and stalling, the other is a bouncing tool.
This is tough without seeing what you are doing since these are symptoms caused by many different things.

stalling the lathe is either too big of a cut or slight catch.

bounging takes all the fun out of turning. Practice good technique and bouncing will disappear.

Marginal Techniques that lead to bouncing:
- not riding the bevel causes to tool to continually want to dig deeper pulling the tool with it.
- tool rest too low - tool tip should be above center
- feed rate fast on an interrupted cut so that the heel of the bevel get hit by the wood after the air gap,instead of being cut by the cutting edge which has move too far.
- Pushing too hard on the bevel the bevel should float over the cut surface.
- Tool tip at the wrong angle keep the flute at 45 degrees or less from level
- not cross cutting the wood - cut from foot to rim on the outside.
 
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Thanks, hockenbery, I should have mentioned your name in the video's I've watched section of my post.

The A frame has been very helpful - amazed at how much stability putting the butt of the gouge on the hip adds.

Learning new skills is always fun, this process takes me back to learning to ski, and the first few times I felt the ski do the work in the turn, you feel the magic and know what it is supposed to feel like, but you don't have the ability to repeat at will.

Appreciate the thoughts.
 

hockenbery

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The A frame has been very helpful - amazed at how much stability putting the butt of the gouge on the hip adds.

Be sure to keep the forward arm straight with the elbow locked.
Students have a lot of trouble with keeping the arm straight.

it feels uncomfortable at first and it puts the cutting edge so much further away that other cuts.

let the tools do the work just like skiing
 
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A hands on play date would work best... As for stalling, when I was first starting, my lathe had 1/2 hp. I upgraded to a 1 hp motor and that helped a lot. As much as anything else, learning how much your lathe can take off in one pass is important. Sharp tools!

The bounce can happen some what from uneven wood till you get it rounded out. After that, if you have noticed, the firmer your grip is on your tools, the more bounce you get. From an old Hollywood movie, "Hold the sword as you would a bird. Too tight and you kill it. Too loose and it flies away." If you have that white knuckle grip, you not only wear yourself out more quickly, you get a lot more bounce. If you have very sensitive hands, you can also feel a bounce from the wood grain. You cut through end grain 2 times for every revolution of the blank. I tend to hold my tools more level rather than the dropped handle method. When turning the outside of the bowl on a long bed lathe, the dropped handle is more common. When turning the inside of a bowl, a more level tool is more common, in part because the lathe bet gets in the way.

I do have a bunch of bowl turning videos up on You Tube as well. Mostly on bowl turning. Most of what I do is done with the sliding headtstock. Can't remember if I have done one on the differences between a long bed lathe and a short bed lathe, which would be the pivoted or sliding headstocks, or some of the dedicated bowl lathes.

robo hippy
 
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I found that bolting down my lathe allows me to rough out at higher rpm's - within reason-, making for a smoother cut. You have to use your judgment as to how much stress an out of balance piece is putting on the lathe once bolted down, but it helped me, as did the technique suggested by hockenberry.

3/4 hp is not much and that is a relatively light lathe so you have some inherent limits. Try adjusting the belt tension, but the Reeves drive may just take up the slack.
 
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Thanks for all the help.

Sharp is always better for sure, but definitely do see this fresh of the grinder, and I tend to run the lathe at full power through VFD and control speed with Reeves to keep the torque.

I'll keep the grip in mind, no sense making an issue worse.

For the belt tension, I'd have to replace one of the belts with a shorter one, as I've got it as tight as possible now. I'm leaning towards one issue possibly being turning too slowly when roughing. Generally, I try to get the speed going to the point where the lathe just starts to move, then back off a hair.

I have successfully made cuts of approx 1/4 inch of material, some of those have been the smoothest cuts reference above, where it is nearly effortless. That gives me some data point.
 

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Thanks for all the help.

Sharp is always better for sure, but definitely do see this fresh of the grinder, and I tend to run the lathe at full power through VFD and control speed with Reeves to keep the torque.

I'll keep the grip in mind, no sense making an issue worse.

For the belt tension, I'd have to replace one of the belts with a shorter one, as I've got it as tight as possible now. I'm leaning towards one issue possibly being turning too slowly when roughing. Generally, I try to get the speed going to the point where the lathe just starts to move, then back off a hair.

I have successfully made cuts of approx 1/4 inch of material, some of those have been the smoothest cuts reference above, where it is nearly effortless. That gives me some data point.

I'm glad that you know for maximum horsepower output that it is necessary to have the VFD output at 60 Hz and to control the speed with the Reeves drive. I'm not familiar with the Reeves drive on your older Delta lathe, but I'm sure that it is much better than the Reeves drive on my Delta lathe that I bought in 2004. On my lathe's Reeves drive there is a spring on the motor pulley that takes up the belt slack by closing the pulley halves. This means that there isn't any way to adjust belt tension ... it is what it is. And, using a shorter belt would only make the drive ratio change such that the spindle would run faster.

Generally speaking, variable sheave belts don't look like your typical A-section belt. Instead they are wider and less height and they are also usually Kevlar wrapped belts as opposed to the raw edges of the typical A-section belt. However, on my Delta lathe it didn't take long for the wrapping to be worn to shreds ... and then the rubber would start wearing.

Some of your problems might be caused by the Reeves drive. On my lathe the spindle speed was affected some by load torque. So, instead of running smoothly the speed sort of fluttered around a nominal value, but this fluttering speed induced quite a bit of vibration into the piece being turned. That lathe is now a dust collector, but not in a good way.

My guess about bouncing and smoothness of cut while maybe partially due to the Reeves drive, is likely a combination of technique and tool sharpness. Your earlier comment about fighting the cut and applying excessive pressure. It's unfortunate that you won't be able to get together with a mentor, but in the meanwhile just keep practicing. Make sure that your tools are surgically sharp and that's not much of an exaggeration. Make sure that you're not scraping the wood (no bevel contact). It sounds like you are having dig-ins that are stopping the spindle which is likely the result of the tool not being presented to the wood correctly to have a bevel riding cut.
 
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I am wondering how old this video is... I would guess pretty old. One reason, no CBN grinding wheels. Another, and I don't know if this is related to his 'peeling' cut on the inside of the bowl or not, but he doesn't grind the heel off of the bevel on his gouge. I never liked that cut because as he points out, if you come off of the bevel even a tiny bit, you dig in really hard and have to start another bowl. I haven't used a swept back gouge in 10 or so years. I wore my first one down to a nub, and got a second one that also wore down to a nub, and I had to grind a flat on it so it would fit into the jig. About that time, I learned the 40/40 grind, and how to platform sharpen. With the 40/40 grind and a bottom feeder, I have no need for a swept back gouge. If I want to shear scrape I use a scraper with a burnished burr.

robo hippy
 
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Thanks again. I watched a couple of videos with David Ellsworth last night, and learned a lot. Also Stuart Batty has some videos on Vimeo which I found very helpful - particularly the ones on defects and left handed turning.

I'm going to modify one of my bowl gouges to an Ellsworth grind later today and give it a whirl. Along with some other things picked up.

In regards to the Reeves Drive. My lathe is the version with the cable control. Belt tension is done via motor positioning, and currently it is a low as it goes, making the belts as tight as they can be. I'm not 100% sure they are right size, as they were not on lathe when I bought it. It does get full motion at both High and low, based on where on the pulley the belts end up.

This is quite an adventure - so many details to keep track of and styles to choose from. That just makes it all the more fun
 
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Yes there are many ways to skin the cat of bowl turning. Learn the different approaches - quite a bit of difference in tools and methods between Stuart Batty and David Ellsworth. One thing they have in common - using the body to control tool movement. I think it’s good for folks to learn different tools/grinds/methods and over time pick what they like, or develop different methods for different situations.
 
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Quick update - turned another bowl last night, and definitely made progress. What was different? Sharpening. Originally my gouge was more of a traditional profile at 60 degrees. Sharpened the wings back significantly more. Tried a lighter approach, particularly with the left hand. However, this gouge is a Benjaman's Best, and the handle is much shorter than my other Sorby gouge. This made it tougher to make that firm A frame triangle. Additionally, I added more speed which also helped. I figured that while experimenting, I should take it out on the cheaper gouge and reserve the Sorby for when I've got the profile that works for me.

Still not able to fully hog off material like I've seen others do, but the cuts were definitely smoother, and stalled the lathe less often. Need to focus more on tightening the tailstock early as well. Some of the stalls are due to inadequate tension, but still had a few where the headstock stopped too.

On inside of bowl, I was able to make a full cut from rim to center multiple times. The gouge I usally use, is a sorby with a 40 degree bevel, so using this gouge with the 60 meant it had to be further away from my body at the rim. Once I got the hang of that difference, the only real issue I seemed to have was about halfway through the arc between rim and center, where the cut got really bouncy many times. What was strange, is that it then smoothed out as I went across the last 3 inches of the bowl bottom (10" bowl).

Thanks for all the advice here, I've found it really helpful, and after the rain passes, I'll go back out and spin some more. Might make a new handle for that Benjaman's best gouge to make it closer to the length of the Sorby. Since I have an abundance of Maple right now, that is what it will be.
 

hockenbery

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the only real issue I seemed to have was about halfway through the arc between rim and center, where the cut got really bouncy many times. What was strange, is that it then smoothed out as I went across the last 3 inches of the bowl bottom (10" bowl).

Depending on the inside curve - It may be tighter in this area than on the bottom or near the rim.
What may be happening is the heel of the bevel pushing into the wood as you cut.
I grind the heel off to shorten the bevel.
 
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Unless you're turning an extremely shallow bowl, you cannot make a continuous cut from rim to bottom center with a 40 degree bevel. The rim gets in the way. If you're going to turn the rim to transition zone with the 40 degree gouge, you'll need to switch to your 60 degree gouge for the rest of the way down.

BTW, if you want a swept back grind, pick your gouge with a parabolic or elliptical shaped flute. (English made tools generally have them)
 

hockenbery

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Below is a link to an article by Joe Larese that provides an overview of gouges.

The photo shows his explanation of hollowing with different bevels. With long bevels (40 deg) the tool hits the rim in a hemispherical bowl. With the Ellsworth Grind (60 deg) the tool is not close to the rim.
It is the combination of a steeper bevel and shorter bevel that make the hollowing successful.
Grinding the heel off the bevel shortens it more.

a shorter bevel goes around the curve easier and it reduces bevel drag due to less contact area.
On the turn to the bottom the tool is furthest over the tool rest. This requires light bevel riding becasuse the bevel drag will want to pull the tool tip downward.

http://www.mendocinowoodturnersguild.org/wp-content/uploads/GuideToGouges.pdfEDDD4BB1-E35D-4227-97DA-C20814F02CCA.png
 
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Thanks again for all the help. Definitely seeing improvements every time I turn.

the stalling issue is minimized as I swapped out belts for a shorter one.

This is the bowl I turned yesterday from a backyard maple round. The crab pattern is a bonus. Still have a lot to learn about fine tuning the finish cuts to avoid tool marks but overall happy with this one.

5CA79428-EE11-4BF7-9D07-F77A20DD6DB5.jpeg

782573B1-E5C0-41DE-B1AE-82730052AED2.jpeg

31AA561C-DF68-42B0-B928-AE276A669CB6.jpeg
 
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Wow, this thread is like gold for bowl-turning tips for a rank newbie like me. I've only turned a few so far (a couple of which I blew up), mostly in English/Claro Walnut and Maple. I just green-turned a super-hard and dense Red-Tip blank with lots of figure that my arborist son brought home. Like Kirk, I was getting a lot of tool chatter even after I thought I had it balanced. The farther up the outside wall I got, the worse it got. It didn't help that it had a huge, uneven bark edge that I thought I was going to leave on, but gave up and cut it off because I couldn't get it balanced. Anyway, I put it away in a paper bag with sawdust at about 19% mc; hopefully, I will have conquered some of my technique issues before I try to finish it.

And that was with super-sharp tools fresh off a 180 CBN wheel, plus a few passes on the insides of the flutes with the Alan Lacer diamond 500-grit slipstone that I just got (it really seems to give me smoother cuts). I think my issue might be more beginner technique issues like tool angle and holding technique. Though I've learned to lock the tool down against the rest and move the tool with my body, I may be white-knuckling things a bit as RoboHippy warns against. I definitely plan to try that A-Frame rigid triangle technique on my next bowl!
 
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Figured it was time for an update, as I've moved on to the next phase of bowl turning, and have found a number of new and interesting ways to create beautiful firewood. :)

First, I recently went through all the bowls I've turned so far which are in the drying phase to get a sense of what is going on, I then put them into two piles, thick ones needing more drying time and thinner ones, ready for sanding. Pleased to say that there was real evidence shown that skills are evolving, both better shaping of bowls, as well as fewer tool marks. Additionally, I noticed minimal cracking - only a couple displayed any, and it was expected, given that those pieces included grain very close to the pith. So far, so good, right?

I've now taken 3 of the thinner walled bowls down for sanding and finishing. Here is the process used: These were turned down to 1/4" or so walls, and had live edges. The bottom had a flat, and in the middle of it, a tenon. Using a jam chuck, I mounted the bowl onto the lathe and turned the tenon round and flat. Then chucked the tenon. Commenced with sanding, inside and out. Once satisfied, reversed again with jam chuck to remove tenon. Here is where things have gone sideways twice. Once, as the tenon was down to 1/2" diameter, and I was trying to further reduce it next to the bowl with a parting tool, I must have used too much pressure, as the tenon pulled out of the bottom.

Proving I'm a slow learner, I tried another bowl. This time, after turning the tenon down to that 1/2", I noticed the outer profile of the flat was not round and had some roughness, and thought I should "adjust it slightly". You see where this is going, right? The little voice in my head said "it's good enough", but was I smart enough to listen? Of course not. Pop went the tenon, and I created another funnel/lampshade. The bottom of the bowl at that point is about 1/16, maybe 3/32".

Funnel.jpg

Now it's time to regroup.

Root Cause Analysis - Bad idea to reduce size of tenon before working on a part of the base with wider diameter. Should probably have shaped the flat at same time the tenon was trued up prior to sanding. Second, should have not been using parting tool, and instead opted for the bowl gouge with a shear cut from the bottom, to avoid hitting the end grain.

Monday Morning Quarterbacking time. For these "once turned" bowls, would I be better off getting rid of the tenon at point of initial turning, before drying the piece, and then sand on a drill press or something? Or is it simply a matter of what I've stated above in the root cause, and doing things in a different order?

I know just about everyone ahead of me on the learning curve has gone through this, but man, I am so bitterly disappointed at this one. Good thing there are another dozen or so still waiting their turn.
 
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when I do once turned, I try and use a shear scrape or etc to get as smooth and tool-less finish as I possibly can (seems to improve the skill a tiny bit each time I do one) so thickness is where I want it, then immediately reverse and jam chuck it and turn off the tenon.. Looks to me like you may need to work on your wall thickness consistency though.. 1/4 inch rim and next to nothing on bottom (Mine tended to be thicker bottom than rim/sides even using a caliper.. too chicken.. LOL!) but yeah, turn off the tenon soon as bowl is finished.. I never try to "touch up" a once turned bowl after letting it dry - there's simply not enough material left afterwards to true anything up again (So, I turn a narrow foot on mine) and do my sanding on the bench (hand and/or 2 inch power drill sanding disks) and call it done.. since pretty much any natural edge bowl once-turned from green, is gonna warp no matter what you do, it is actually promoted as a feature making each bowl unique..
 

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and have found a number of new and interesting ways to create beautiful firewood
"artisanal firewood"

And like Brian said, if you're going for a once-turned piece, go ahead and finish all the turning (like removing the tenon, etc) initially. The only thing to maybe leave for touch-up is the foot/base (if/when it warps, you need a bit of leeway to sand it flat).

I wouldn't use a parting tool on a bowl's tenon - gouge or scraper, basically like you would anywhere else. And don't feel like you have to turn the whole thing off, just take it down to a little nub that you can sand away.

After it's dry, if you want to sand on the lathe, mount it between padded things on both the head and tail stock. (This is often called a jam chuck, but is probably more accurately called friction or compression chucking - meh, whatever). To avoid the point of your live center digging in to your finished bowl, just turn a little wooden "cup" to cover it. Glue some rubber or something to it for grip, if necessary.
 
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"artisanal firewood"

And like Brian said, if you're going for a once-turned piece, go ahead and finish all the turning (like removing the tenon, etc) initially. The only thing to maybe leave for touch-up is the foot/base (if/when it warps, you need a bit of leeway to sand it flat).

I wouldn't use a parting tool on a bowl's tenon - gouge or scraper, basically like you would anywhere else. And don't feel like you have to turn the whole thing off, just take it down to a little nub that you can sand away.

After it's dry, if you want to sand on the lathe, mount it between padded things on both the head and tail stock. (This is often called a jam chuck, but is probably more accurately called friction or compression chucking - meh, whatever). To avoid the point of your live center digging in to your finished bowl, just turn a little wooden "cup" to cover it. Glue some rubber or something to it for grip, if necessary.

Dave, thanks on the idea for the tailstock cup. That while probably a very old idea is one that is new to me, and certainly would come in handy.
 

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Dave, thanks on the idea for the tailstock cup. That while probably a very old idea is one that is new to me, and certainly would come in handy.
The next "upgrade" to that is to take your live center to the hardware store and find the right size nut to thread on (mine are 3/4-10). Epoxy nuts into holes drilled in scrap pieces to make whatever size thread-on things you need (having different sizes and shapes comes in handy). I thread the epoxied scrap onto the live center, and drive it with friction to cut a tenon in the "back side" (tailstock side). Then flip it around, chuck it up and profile it as needed. I have some turned flat and some domed and some cones. And with an aligned tenon, re-profiling for a specific task is easy.
 
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Well, coffee hasn't kicked in yet... Anyway, looking at the tenon piece that broke off, is your bowl maybe 1/16 thick? I do prefer to leave the bottom a little thicker, just in case of accidents like this. On my once turned bowls, I use a recess, in part because I can remount it for sanding, which is easier than holding it to sand, and easier, for me anyway, than wet sanding. I do have a video on Finding the bottom of the bowl. My method is simple for standard bowls, It does work for NE bowls, but I seem to remember some one finding a more simple way...

robo hippy
 

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these "once turned" bowls, would I be better off getting rid of the tenon at point of initial turning, before drying the piece, and then sand on a drill press or something? Or is it simply a matter of what I've stated above in the root cause, and doing things in a different order?
I know it is disappointing. You will get it....

I think you are on the right track but using a spindle gouge or small bowl gouge will give better results.
also when the nub gets to 1/2” diameter cut it close with a fine tooth saw. back saw, copping saw. Japanese pull saw.
after a couple turn it down more Before sawing.

With a small diameter pin keep the tool rest a little high. cut more on top of the pin. If i cut on the from like I woul cut on the bowl I run the risk of getting the gouge pulled under the pin and breaking it.
a few screen shots

4D1C14E9-E4BE-44EF-8C2B-8AE42278227A.jpeg78AD071D-6894-4D1B-844D-4CEA42055690.jpeg4190DB51-7382-47E3-A0B9-726844863C1B.jpegF6040C91-9C5C-4B48-8C97-ACEBD6CF7657.jpeg
after you cut a 4 or 5 with a saw toucan try cutting the bowl free with the gouge Turing the bowl by hand

1BCE2874-C2F3-46BD-9C79-672D6B847353.jpeg


this is how i revers chuck.
Fast forward to 52 minutes. I measure the thickness
53:45 I use a jamb Chuck similar to one in your photo
55:40 start turning away the tenon - light cuts with bowl gouge
58:08 start tuning the 5/8” diameter nub with spindle gouge
59:50. I have turned a small bump on the bottom( will sand off in seconds) cut the last bit free turning the bowl by hand

View: https://www.youtube.com/watch?v=8jVoI12Kfug
 
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Catching up:

Dave, I am completely lost on what you are describing. My live center is just that, a live center. Think it came from Woodcraft - sounds like you are describing something that can be done with one of the live centers which come with different attachments. I don't believe it is designed to come apart.

Robo - yes, the bottom was approx 1/16 - 3/32 thick at that point. I guess I took the advice to make the bottom of the bowl thinner than the sides of it a bit too literally. Also I lost a bit of depth, maybe another 32 or so on the foot as I turned it flatter. I've had trouble making recesses on my lathe, as the tailstock does not have a super long throw, and the width tends to get in the way.

Hockenberry - thanks, the pictures make sense. One thing that is somewhat confusing though - I was given advice a while back concerning gouge types that they correspond roughly to difference between cross cut and ripping saws. Bowl gouges being cross cut and spindle being ripping. That said, I tend not to use a spindle gouge on a bowl. Now I can see how having the longer point would help getting into the tight space.

Appreciate all the help.
 

Dave Landers

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Dave, I am completely lost on what you are describing. My live center is just that, a live center. Think it came from Woodcraft - sounds like you are describing something that can be done with one of the live centers which come with different attachments. I don't believe it is designed to come apart.
Oh, sorry - a bad assumption on my part. The live centers that came with my PM and my Jet are like this (also similar ones available from Oneway, Robust, etc). There's a threaded part on the end, usually to attach/remove a cone.
For the one like I think you have then ignore my comment and stick with turning a "cup".
 
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Oh, sorry - a bad assumption on my part. The live centers that came with my PM and my Jet are like this (also similar ones available from Oneway, Robust, etc). There's a threaded part on the end, usually to attach/remove a cone.
For the one like I think you have then ignore my comment and stick with turning a "cup".
No problem. Say, might you be suggesting that there is another tool/accessory I might need? ;)
 

hockenbery

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I was given advice a while back concerning gouge types that they correspond roughly to difference between cross cut and ripping saws. Bowl gouges being cross cut and spindle being ripping.
That is confusing advice to me. The best gouge cuts are always in the cross cut direction
Using a spindle gouge to make beads and coves on a spindle the cuts are mostly cross cut to the long grain.
exception at the bottom of the cove where the cuts from each side meet.

when you get down to the nub the cuts alternate between a rip cut straight into the endgrain toward the point if the cone and a mostly cross cut from the tailstock to the tip of the cone

this is a rip cut
A90D0584-B24E-44C6-BC48-A94A4972DCDE.jpeg
 
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Well, that bottom being too thin was a big contributor to this accident. When twice turning, I believe it is common to leave the bottom a bit thinner than the walls, Mostly this is because there is less warping across the bottom than around the walls. For final turning, I want the bottom to be the same thickness or even a bit thicker than the walls. It helps even out drying stresses.

The tailstock should not be a problem when turning the inside of a bowl. Unless you are coring, you can leave a tower in the center of the bowl as you turn the walls down to final thickness. Since I core just about anything over about 4 inches thick and maybe 10 inch diameter, it is a non issue with me. Most of the time I don't have the tailstock engaged for turning out the inside of a bowl. You do need to learn to make the proper sized tenon or recess for the size of bowl you are turning. Keeping the tailstock engaged can do a lot to reduce vibration issues with larger bowls. Not necessary on smaller ones. The bowl in the picture looks to be about 12 inch diameter. I might have used a tailstock on it, but probably not, but that is me.... For sure, it might allow you better access for turning out the inside of the bowl. I have found it almost impossible to core, using the McNaughton, and keep the tailstock in place.

robo hippy
 
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Looks like you are progressing just fine. Continue using free firewood to build confidence and skills.

For 1 turn bowls, keep the walls and bottom the same thickness, bottom can be a bit thicker. Use a spindle or bowl gouge for tenon removal, not a parting tool.

I leave a tenon on 1 turn bowls so I can use the chuck as a 3rd hand to hold the bowl - most of the sanding is with the lathe off. I use a large tenon to make the bowl, with a shoulder above the jaws to enable a continuous curve down to the bottom. I then jam chuck the reversed bowl and cut the tenon down to ~2” or smaller, depending on bowl size, and remove the “shoulder”, creating the desired foot shape (or no foot). Then the bowl gets dried. A large tenon helps support the bowl walls while cutting, and a small tenon will support the sanding.
 
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Went back to the lathe this weekend, and had some better outcomes. Completed a couple "once" turned bowls specifically one in Maple. This one has a couple of darker rings towards the bottom which are compeltely smooth, but refused to be sanded out. Might this be bruising from the bevel?

Bowl1.jpg
Turned a new one in oak, guess it is art by the definition of not holding soup.
OakBowl.jpg
Then took on the first bowl I roughed out back in December. This one is cherry. First roughed
CherryRoughed.jpg

Here is completed - the orange ring in bottom was how the cherry dried, was possibly too concerned about breaking through, so I left it.

CherryFinished.jpg
Finish on all is Mahoney's Walnut Oil.

Thanks to all for the advice and help, nice to have a few that worked out.
 

hockenbery

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Might this be bruising from the bevel?
bowls are getting nice shapes and surfaces.

I think this ring is most likely slightly torn grain.
probably came off the bevel here tore the ring and got back on the bevel.

grinding the heel off the gouge bevel will shorten the bevel and let the gouge make the turn unimpeded.
cutting at a slower feed rate might help too.358F5DDC-6C4F-4BAD-860E-FC056AD1E11F.jpeg
 
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I would guess that the rings on the sides are most likely tear out, and possibly the one in the bottom. The tear out seems to span the down hill/with the grain and the uphill/against the grain. That could mean dull tool, and/or pushing too hard. The last 1/16 to 1/8 inch of material to come off the wall should be delicate cuts. Some times a good shear scrape with a scraper can remove those marks, but you have to do it immediately. The marks from bruising usually are rings that go all the way around the bowl, so these rings could be from bruising as well, You get a lot less bruising marks when you round over the heel. I grind away at least half of the heel, and make it rounded, not another flat bevel because that can also leave bruises.

robo hippy
 
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