How round should a bowl blank be?

[Lee DeRaud]

(I mean before turning.:p )

Is it good enough to just "octagon" the corners off in the miter saw or do I need to make a circle jig for the bandsaw or something in between?

I'm talking smallish, 5"-6" by 1.5"-2" thick blocks, dry wood.

Just killing time until the glue cures...:cool:

[Don Baer]

Lee,
The rounder the better in my opinion. But hey I'm still learning. I put a 6" square piece on my old lathe and just about beat myself to death getting it round to start a bowl. I now have a circle cutter for my band saw and sure do love it.

[Mark Cothren]

I just knock the corners off with a chainsaw and then chuck it up and start turning. Most of my turnings are green wood, so it only takes a few minutes to get it rounded up good.

[John Shuk]

I wouldn't go too crazy. It'll come round pretty easy.

[Jim Stoppleworth]

In my short turning experience I've found rounder is better to cut down on vibrations. When I first started roughing out bowls my band saw was a 12" and I kinda just cut the corners off. I changed to a 17" bandsaw and cut them close to round and the vibrations are considerably less while I true and rough the blank.

Jim

[Reed Gray]

I used to cut everything out with a chainsaw (an octagon). If you have the variable speed lathe where you can start turning at 100 rpms or so, it isn't much of a problem. I had a 4 speed atlas to start with, and I had to use my 250 lb. body, added to the 400 lb. lathe bed and frame to keep it from walking all over the shop. It doesn't have to be perfect, after all, a lathe does a good job of making things round. Now I am spoiled rotten. I got a big bandsaw, and cut out my blanks on it. It is faster, less noisy, and more accurate than the chainsaw. Also, you can start at higher speeds, and there is less roughing work to do.
robo hippy

[Bernie Weishapl]

Lee I would make a 5 or 6 inch circle on my blanks and cut them out on the bandsaw. I tell you when you are learning to do bowls it makes it a whole lot easier to turn. Just my experience.

[Andy Hoyt]

If it's green I'll do like Mark and make an octagon.

If it's dry I'll do best to get it round on the bandsaw.

That's the protocol anyway. In practice, it often changes due to such issues as:

If the Pats beat the Packers
Gold Standard value on the Kyoto Exchange
How lazy I'm feeling at the moment

[Cody Colston]

I think the roundness of the blank is dependent on the size lathe you use.

If you have one of those 2 thousand ton behemoths like a Oneway 2436, you probably just lop off the corners with a chainsaw.

OTOH, if you have a JWL 1236 like me, you saw them as round as possible on the bandsaw using a template and then carefully mark the center before mounting on the lathe.

A 11 inch out-of-round blank on my lathe (550 rpm min speed) will make it do the Watusi.

[John Hart]

I kinda like that Watusi thing that the lathe does. :D

I'm kinda like Andy....depends how lazy I am at the moment. Especially if the blank won't fit under my bandsaw...then I'll put just about any shape on the lathe.

[Jim Dunn]

I'm with John:eek: I find I can turn and get my excersise, (who says woodworking aint work,) at the same time chasing my lathe around, then putting it back in place. No fair if it's on wheels:p Add calories if you have to do lunch while turning.;)

[Bill Grumbine]

Lee, after you get the answers to this one, perhaps you should start thinking, how round should it be when you are done! :eek:

<img src="http://www.enter.net/~ultradad/blacklocustcrotch02.jpg">

For smaller, lighter lathes, rounder and more balanced is better, but you can turn pieces like this on your mini once you gain confidence.

Bill

[Lee DeRaud]

For smaller, lighter lathes, rounder and more balanced is better, but you can turn pieces like this on your mini once you gain confidence.For something like that, at my current skill level, I'd want some tools where I can stand further away from the lathe.
Like maybe a 2-iron. :eek: :o

[Curt Fuller]

The rounder it is the faster it changes from a chunk of wood to a bowl. But if you're trying to get as big a bowl as possible from the swing of your lathe then the rounder it is to start with, the bigger you will end up with. You can turn a bowl pretty close to 12" in diameter from a 12" round blank. But you'll end up with considerably smaller bowl from a 12" square or octagon.

[Jim Becker]

There is no reason it needs to be "round" prior to turning...many folks prefer that, but it also means you can't play with the blank between centers to find the best orientation for turning the material. This is especially important when burls or other figured stock is involved. That said, if you have a lathe that is not VS and has a relatively "high" lowest speed....pre-rounding is a good thing for both safety and avoiding "walking" the lathe around your shop.

[Pat Salter]

I was really enjoying this thread until I saw Mr. Grumbines, then I couldn't stop laughing:D

I'm fortunate that I have a hefty chunk of iron for a lathe so it doesn't matter too much. The only reason I knock off corners is to make it fit on the lathe. I only have a 12" reach so I shoot for about 11". I don't like to take off too much because I may want to remount the piece after I see what the grain is going to do. Especially if it's going to be a natural edge piece.

Having the pieces precut on the bandsaw is helpful if you can't get your lathe to go slow enough too. (Safety first people!) But I may start off with a piece that has 4 corners. It really doesn't take long to round it off. Even at slow speeds.

BTW, Mr. Bill, that's a beaut!