Huge walnut bowl, no rig

[Sam Beagle]

I'm working on the biggest piece I've ever done. It's actually bigger than a 5 gallon bucket. Anyway, been hollowing w a carbide cutter on a long homemade handle. Anyway, it's to deep now. I just had it tear the tool from my hand and slam my fingers real bad. So I'm looking for suggestions, minus getting a hollowing system. I have a new 3520B, it's got unbelievable power, I have about 3 inches of hollowing to go. I just had an itch to make a monster cauldron today.

[Kyle Iwamoto]

I've turned something that big using my Monster Hollower, but I do have the "big" bar and a real long tool rest that I can stick inside the turning... I made a lampshade. On purpose.... Really. Monster is back in business, if you've been following that thread. I had to plug them. I like the rig. Lots of bang for the buck.

[Roger Chandler]

If you can find a way to get a rest of some sort into the form perhaps as much as 6" into the inside, then the additional support that is closer to where you need to finish will probably allow you to finish that last 3" of hollowing out.

Some manufacturers like Robust Tools and Best Wood Tools have inside rests.....it depends on the diameter of the opening if one will go inside......just some thinking here, but if your opening is large enough to accommodate an inside rest you will have enough support to finish.

[Sam Beagle]

That's what I was thinking too, some way to get inside. It did scare me a bit when the the lathe grabbed, my old delta would just stop, this powermatic is for real.

[Brice Rogers]

Roger gave you very good advice. If you have long straight rest (like maybe 14", you might be able to angle it inside of the bowl. I read somewhere that it is a good idea to not have any more than 20% of the tool overhanging. Less is better. More is asking for chatter or a catch. Also, it is wise to be cutting above center when inside a bowl. That way, a catch will tend to knock the tool into dead space rather than resulting in a major catch. Also, higher speeds reduce catches, but with a really big bowl, I would be a little reluctant.

BTW, I have made over a half dozen tool rests. A semi-circle that can go into the bowl is a good purchase or a good thing to make. That way, I can often position the rest within an inch or two of the inside. If you can't build a rest, then you should buy one.

[Reed Gray]

The problem with going deep is getting good tool support. The Robust and Oneway inside bowl rests extend out from the banjo maybe 6 inches, maybe a bit more for the Oneway. So, they are better than a straight rest. Other than that, you need specialty tools. How far you can hang out depends in part on your handle length and bar diameter, and in part on how much of a cutting edge you have on the end. Most of the deep hollowing tools have 3/16 or 1/8 inch square tips for the reason of less pressure when cutting. My experience with my Monster articulated hollowing system is that it is excellent for fine finish cuts 6 to 8 inches off the tool rest, but beyond that, it starts to chatter.

robo hippy

[Brice Rogers]

Hi Reed,
I watch and admire your videos. Thanks.
Why are the deep hollowing tools equipped with square tips? Why not rounded (like a half-round "D" ) ? I'm not challenging- - just trying to better understand from a more experienced turner like yourself.

[Brice Rogers]

Sam,
You posted: " I just had it tear the tool from my hand and slam my fingers real bad. " BTW, last June I was working with a chunk of wood that was bigger than my lathe and more importantly, that the tool rest could handle. I was working at the limit of the tool rest. I got a catch at the end/side of the tool rest - - it took the tool over the side and downward. Unfortunately I had my left index finger anchored on the rest. The catch shattered the middle bone of my finger. Seven pieces.

So - - my advice to you is to not try to push beyond the limit of your tools unless you have great insurance and a desire to use it.

[John K Jordan]

Sam, as for getting inside, without buying or building a special tool rest can you rig up a temporary long rest? I'm imagining a long piece of steel (bar, angle iron, channel, etc) or wood clamped to the top of the rest with the back end stabilized by fastening to something clamped to the lathe bed, a kind of second banjo, and the front end extending deep into the turning. A long piece supported in two places could be very strong and stable. I've seen home made tool rests made from wood for a special purpose such as a very long turning.

I would just weld one up but you may not have the equipment for that.

For something large I might consider making a very long handle or extending my tool handle with a "cheater" bar, perhaps a pipe or a rod or something made from wood clamped to the tool handle with hose clamps or something. Even better would be one with a short handle perpendicular to the shaft that you could grip with the left hand and prevent rotation. I have a right-angle grip made for an electric drill that would be easy to mount on a tool handle - maybe you have one of those. Such a grip could keep your hand safely out of the "bucket."

(Also, I'd hate to give up but if turning safely isn't going to work out, I might consider a redesign to make the form a little shorter.)

BTW, just this week I set up a PM3520b in my shop. I've been turning with a couple of Jet 1642s. Although I've turned on PMs in the past, this is the first one of my own. I like it! It's nearly twice the weight of the Jets and a lot more power. This one has the bed extension so it is even longer than the 1642s. Of course, with a bigger and stronger lathe, what's the first thing I turn? A little finger top!

JKJ

[Reed Gray]

Your hollowing bits come in all sizes and shapes. John Lucas shows a square one and how to sharpen it, and this type of bit is what the radius edged CBN wheels were made for after a suggestion from David Ellsworth. As you sharpen, you round the nose profile, and as you push the bit around the edge of the wheel, or pivot it, the sides of the bit get tapered a little. There are round bits, but you have to take the cutting part down to half round like the skewchigouge or Doug Thompson's fluteless gouges.

Another point on safety, I don't usually have my left hand, or right hand if I am going the other way, anchored on the tool rest. Maybe very gently resting on or near it, but Anchoring the tool on the tool rest (A, B, C, anchor, bevel, cut) takes little to no effort because gravity and the wood moving down do that just fine. A friend almost lost his thumb from a scraper going past dead center, and coming back up and around onto his thumb....

So, how deep is this bowl? Or is it a hollow form/lamp shade/barrel?

robo hippy

[Don Bunce]

You can loosen the belt tension a bit so that it will slip instead of having a catch.

I use a rounded profile for hollowing also.

[Olaf Vogel]

I do quite a few large, deep hollows, often of black walnut.
in an attempt to learn from those who have gone before me, I spent a lot of time looking at Ed/Matt Moultorp's techniques....there's not much online.

but a few things they do are interesting
- they use VERY long handles. Up to 6-8 feet long. Admitted their work is huge, but I've gone as long as 4 feet. It adds a ton of stabili and control.
- the tool rest is flat and uses pegs in it. So no need to have your hand on the rest. (Likely the only solution if you are standing 6 feet back.).

So I drilled out a tool rests, added some pegs and tried it out. Works well.
that won't prevent a catch. I fact it's easy to overpower the chisel due to all the leverage, and requires learning a new set of skills and subtly.

But this way, I have been about 20" off the tool rest, without issues. (Although my captive bar system was holding onto the end then, since I had about 33% overhang)

[Steve Schlumpf]

Sam - this is one of those times that a few photos would really help everyone with offering sound - and safe - advice.

[Gregory Cowart]

You said you didn't want a hollowing system. If and when you do, look at this one. I had one, in a former life and wish I had it back. http://www.theokspindoctor.com/Clark-Deep-Hollowing-System-p/hb.htm This thing is solid. Actually more than solid.

[William Bachtel]

Sounds like you may want to start with a little smaller bowl, and then work your way up to bigger bowls. That said,
Robust can make you an offset toolrest , from the center of the 1 inch post, it is 9 1/2 inches to the end of the rest, I love mine and use it all the time, this will also give you clearance,for the post and banjo better. If you want I will send you photos just email me.

[ALAN HOLLAR]

For large open bowls the sort of semi-circle rests like the Oneway or the Robust curved rest are good. For forms that are deeper than they are wide, the Robust J rest is a better choice. Once you move up to the larger more powerful lathes the temptation to do bigger work is great. I have found that a custom rest or two, made of wider, thicker, longer stock adds safety and comfort to more ambitious undertakings. If you are not handy yourself, look for a small local machine shop.

[ron david]

That's what I was thinking too, some way to get inside. It did scare me a bit when the the lathe grabbed, my old delta would just stop, this powermatic is for real.
some jump from the pot into the fire. bigger lathe - bigger bowl and don't learn the steps in between. always get as close to the working surface as you can. if you can't then you have to improvise and perhaps observe the law of physics. the further over the tool rest, the further one should go the other way to balance out the pull. imagine a teeter-totter when you were a kid and on one end is a fat kid and a skinny one on the other end. doesn't work unless you move the board ratio until it balances out and work. in this case it means a sturdier tool, longer and perhaps a smaller tip(smaller tip means smaller cut but less pressure. also takes longer).
I have worked 24" over a tool rest with the following tools. they may not win a beauty contest but they do the job that I want. just the cost of materials as they were also not difficult to make.
there is a learning curve for all of this. if you have more power than you can handle then have then think about what you are doing and about how you are going to approach it. mistakes can be deadly!!!!!!
http://imagizer.imageshack.us/v2/1600x1200q90/922/yIej26.jpg
http://imagizer.imageshack.us/v2/1600x1200q90/921/V6OBfB.jpg
ron

[Olaf Vogel]

. in this case it means a sturdier tool, longer and perhaps a smaller tip(smaller tip means smaller cut but less pressure. also takes longer).
I have worked 24" over a tool rest with the following tools. they may not win a beauty contest but they do the job that I want. just the cost of materials as they were also not difficult to make.
ron

Ron, so this is solid stock for e first part and a hollow pipe for the rest of the leverage? And a 1/4 Bit in the front?
seems like a good solution.

[ron david]

Ron, so this is solid stock for e first part and a hollow pipe for the rest of the leverage? And a 1/4 Bit in the front?
seems like a good solution.
the round one is 1" with a 3/8" carbide tip and the other is 1" hex with a 1/2" carbide tip. one can also use h/speed tool blanks
ron

[robert baccus]

Also remember no matter what the depth a bottom feeder cutting tip works very well to prevent catches.