Band saw sled for sawing off bowl foot

[Ben Pierce]

I'm working on a jig for my band saw to securely hold a finished bowl vertically, allowing the foot to be sawed off. I use faceplates, sometimes with glue blocks but most often not, and the 3/16" parting tool kerf is often more than I care to sacrifice. If the band saw can cut the foot reliably right at the point where the screws bottomed out, then a bit of sanding will finish the bottom off easily.

Has anyone designed such a jig? Hard to believe this is uncharted territory.

[Roger Chandler]

I guess each one of us has our own preferneces for finishing off bowls, .........me, I think it would be a lot easier just to use a jam chuck. I finish off bottoms of bowls in just a minute or so using either a jam chuck or ocassionally a vacuum chuck, but most of the time I use a jam chuck.

[Ben Pierce]

I usually part the bowl down to about 1", saw, and then sand off the remnant w/ my bowl on a Longworth chuck. Jam chucks seem like they take quite a while to prepare, no?

[Ben Pierce]

I should have mentioned... I only use the Longworth for sanding. The times I've attempted chisel work w/ the Longworth have not ended well.

[Reed Gray]

The Longworth chuck supplies the drive, the tail stock keeps it from coming off. Keep engaged till there is only a tiny bit left.

robo hippy

[Kyle Iwamoto]

Yes, turn the foot off. I think it's much safer than a sled on a bandsaw. You're already at the lathe. I turned a few friction drive jam chucks. Not quite a "jam" chuck. I just pick the one that matches the bowl and use a blue paper towel to save the bowl from the jam chuck and provide the drive.

I like the LW chuck. The main benefit for that is you can re-mount the bowl back on there and get it pretty close for a second try at getting the bottom of the bowl the correct thickness. Too hard for me to dig it out of the tool storage. I usually just use the jam chuck. I'm getting better at the bottom of the bowl thickness. And yes use the tailstock as long as you can. And I also learned the hard way, use light cuts, and cut towards the headstock, do not cut across the ways.

[Michael Mills]

I do like Kyle and others and use a friction chuck. You can make a jam chuck but for me the waste wood and time necessary to turn a recess to fit the rim of the bowl is too much trouble. You can make a friction chuck each time or have three or so for different diameter bases. I try to the have the chuck about an inch larger than the base. This puts the support where you will be cutting so a 4" base I may use a 5" chuck.
Make the end flat (or slightly concave) and round the edge slightly. Scrap leather, thin foam, a used mouse pad, or the rubber thingies from the kitchen to assist in opening jars make a good friction drive surface. Just place the material over you friction chuck between it and the bowl interior.
I can usually turn down to at least 1/2" and most of the time 1/4" nub. You can sand and add decoration to the base while using the chuck except for the little nub to be cut off and sanded later.
If you don't have a scroll chuck mount a waste block to your face plate and turn a friction chuck on it. You can still keep it for the next time but you may have to re-true a little because it may not remount to the faceplate exactly the next time.
You do want a dimple from the tailstock for the center when mounting. If you used a faceplate and do not have a dimple make one of these to mark the center before you remove the faceplate from the work. (Yes , I know when I took the pic I inserted the center finder from the wrong side of the faceplate).

[Robert Henrickson]

Yes, turn the foot off. I think it's much safer than a sled on a bandsaw. You're already at the lathe. I turned a few friction drive jam chucks. Not quite a "jam" chuck. I just pick the one that matches the bowl and use a blue paper towel to save the bowl from the jam chuck and provide the drive.

I agree, whatever the size of the bowl (or plate, etc). Over some years of turning many sorts of things, I have accumulated a couple dozen of these (friction) jam chucks, with a wide variety of diameters (perhaps 1"-5"), lengths (likewise), and end profiles. I now usually have what I need. Occasionally I need something different, so I take several minutes and make another from scrap and add it to the collection. For padding I use scraps of carpet underpad, pieces cut from cold drink cozies, drawer padding material -- whatever comes to hand.

[Prashun Patel]

I don't agree that the lathe is necessarily safer than the bandsaw. There's nothing wrong with what you're proposing.

It may not be so simple though.

I'd think you'd want a cradle that adequately supports the bowl. Such a cradle would be unique to the shape of the vessel, though...

[Michael Mills]

I looked up this video by Mike Peace which is excellent.
Some terms are a little interchangeable with some folks.
About 32:30 he shows what I learned as a "jam chuck".
About 1:14:00 is what I consider a "friction" chuck; even he refers to it as jam.
One of the easiest and giving full support is the "donut" chuck at about 1:12:00. If I had one it would be a donut chuck rather than Cole jaws or Longsworth chuck. With any of these type you really can't mount natural edge bowls as you can with a friction chuck.

You may want to view the entire video as he covers almost every holding method.


https://www.youtube.com/watch?v=aUXil-5dEeo

[Ben Pierce]

Thanks for all the good input, folks. Sounds like I need to make more use of the tailstock, which I'm not used to doing. I think I will pursue the bandsaw sled as well. Will post photos if it turns out well.

[Roger Chandler]

Thanks for all the good input, folks. Sounds like I need to make more use of the tailstock, which I'm not used to doing. I think I will pursue the bandsaw sled as well. Will post photos if it turns out well.

Ben..........I am not trying to discourage you from a sled to cut the feet off bowls.............just know that what you are proposing, no doubt can be done, is likely inherently dangerous, unless your sled design is capable of adjusting to different size bowls and profiles, and can cradle the bowl form at least 1/2 the diameter or more. Round things and bandsaws usually end up fighting with one another, so just please be very careful...........you want to keep all 10 fingers you were born with!

All I was saying was that jam chucking is easy, fast, and to this turner a preferred method, and yes as you have heard tailstock pressure is key and just leave a very small nib which you can take off with a chisel and sand away to flush on the bottom............easy, peasy! :)

[Thomas Canfield]

I usually part the bowl down to about 1", saw, and then sand off the remnant w/ my bowl on a Longworth chuck. Jam chucks seem like they take quite a while to prepare, no?

You can use a "loose" jam block with soft surface (I use cheap rubber shelf liner) inside the piece and the live center in the tail stock in a dimple/center left in the piece. That will allow you to turn/sand/finish the bottom down to a small section to be removed with saw/chisel and hand finished. I have used that method for pieces that would not fit in a donut chuck or had surface features (cracks, worm holes, etc) that would not allow use of vacuum chuck. The jam block can be designed with tenon/recess to fit a chuck or even tapped to fit the drive, and does not have to be very fancy. You only need a ring of contact with the pad and it should be outside the area being turned for best stability. My jam material ranges from MDF to 2x 4 to 12 construction material - cheap or scraps.

[Jim Colombo]

Ben..........I am not trying to discourage you from a sled to cut the feet off bowls.............just know that what you are proposing, no doubt can be done, is likely inherently dangerous, unless your sled design is capable of adjusting to different size bowls and profiles, and can cradle the bowl form at least 1/2 the diameter or more. Round things and bandsaws usually end up fighting with one another, so just please be very careful...........you want to keep all 10 fingers you were born with!

All I was saying was that jam chucking is easy, fast, and to this turner a preferred method, and yes as you have heard tailstock pressure is key and just leave a very small nib which you can take off with a chisel and sand away to flush on the bottom............easy, peasy! :)

+1 with what Roger said. I almost lost a finger on the "SAFE" bandsaw trying to cut a round piece of wood.

Jim

[Ken Fitzgerald]

I use a donut chuck to turn the foot off my bowls.

[Barry McFadden]

I apply the finish to the inside and outside of the bowl and then put it on my Jumbo Jaw set to turn off the bottom and then sand and finish the bottom http://www.leevalley.com/en/Wood/page.aspx?p=20242&cat=1,330,69091&ap=1

on bowls that are too big for the jumbo jaws I leave the bowl on the chuck and tilt the bandsaw table to the right angle to get a straight cut and run it through keeping the bowl and chuck in contact with the bandsaw table. The foot on the bowl in the picture is too short for this procedure it's just showing the setup I use. Then with a very small foot left after cutting I use gorilla tape to fasten the bowl to the Jumbo Jaws since the rubber feet won't hold it because of the size, then carefully turn off the remainder of the foot. I know it's not the most sophisticated method but it works well for me....

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[Peter Fabricius]

Clearly there are many different ways to finish the bottom of bowls. My vote is for NOT using a bandsaw!
This morning I worked on 6 bowls to finish turn the bottoms. I usually collect them up in small batches just because it is easier to set up the holding system. Two minutes for the Vacuum Chuck, Jam and Friction chucks more time if you do not have the right size, I never use my Donut Chuck or my Longworth Chuck anymore because the three sizes of Vacuum Chucks are so convenient.
So, Vacuum Chucks are best for me, always using the tailstock in the dimple left over from starting the piece between centres (almost always between centres, just too good not to do this).
As I said the six bowls were easy and quick to finish off, including signing the bottoms and applying a first coat of Minwax Tung Oil. Two were Natural Edge, one with a rounded over top edge with undercut hollowing. Just saying, easy to set up and quick to use. The last little nub 1/8" to 1/4" is turned off with the bowl held by vacuum. Then some light sanding, decorative lines and signing, numbering... All good, some steel wool tomorrow and coat number two of Tung Oil.
Peter F. Be careful with that bandsaw!

[Ben Pierce]

Guys, the bowl would be clamped securely to the band saw sled w/ fingers nowhere near the blade, so I am not too worried about the danger aspect. Still, I have not used my tailstock a whole lot (got in the way of the tool rest on my previous machine), and I appreciate the ideas.

[Michael Mills]

I know I departed from the original question.
On the bandsaw I would make a 16X16 plate to mount the bowl to. A bracket on the backside for it to ride the BS fence, then use blue painters tape to tape the bowl to the plate (no residue with the painters tape). Should be able to slide it though with little danger.
For me, in-between the BS and a friction chuck method would be a belt sander with a fine grit and a steady hand.

[charlie knighton]

sounds like minor tendencies to be flatworker with high price machines gathering dust and odds and ends

[Mark Greenbaum]

Trying to cut off foot with a band saw is inherently dangerous. I use a jam chuck technique keeping speed down, and all force running towards the chuck, with tailstock in place as long as possible. Use a spindle gouge to whittle the nub down and break of after the lathe is stopped. A club member (full-time turner and former president of the club) showed me a slick trick at the show we were demonstrating at. He used an oscillating cutter to shave the nub clear off, leaving it almost ready for finish. HF here I come on the next sale day.

[Leo Van Der Loo]

It is Dangerous to use a bandsaw to saw a round piece of wood.

The reason is that the blade will pull the wood down and with a round piece of wood it will rotate forward into the blade, you have an accident waiting to happen, at best damage to the saw and blade, worse :eek: :eek:

Imagine what will happen with something like in this quick rough sketch !!, DON’T DO IT !!!!!

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[Ron Rutter]

Ben. This is the one statement made on this thread that you should pay the most attention to;

" Round things and bandsaws usually end up fighting with one another, so just please be very careful...........you want to keep all 10 fingers you were born with!"

[Roger Chandler]

Ben.........I was trying to be diplomatic and sort of nudge you to a conclusion to not do the sawing a foot off the bowl on a bandsaw........as you can see, by Leo's and others posts above.......you should come to the same conclusion.............

Bad idea.........REALLY bad idea! It is inefficient, unnecessary, can be accomplished in such a safer and simpler way and is so less complicated if you just learn to use tailstock pressure and a jam/friction chuck..............

I hope the op in this thread will take a second and third look, and if necessary a fourth, for his safety's sake!

[Bruce Lewane]

I tried it once. Only once.
Got a catch, ripped a chunk out of the bowl, threw it across the shop and bent the blade
to the point of uselessness.
I have a couple of low end PSI chucks with flat jaws and extensions.
I just chuck it up and turn the tenon off keeping the tailstock in place as long as possible.
Actually, no matter what I'm doing I keep the tail stock in place as long as possible
being adverse to pain, be it physical or psychic, seeing something I labored over destroyed beyond recovery.