turning blank size

Re: turning blank size

DW

>Brad,

Preparation of blanks depends on several things:

The distance from your drive center to the bed X 2 equals the maximum diameter your lathe can handle.

The length between your drive center and tail center is the maximum length.

Now, using those maximum's you have to decide what you are comfortable with as far as dimeter and thickness. Depending on your chucks, you can turn several size bowls with a worm screw and no tail support. However, once you reach a size, say 6" diameter and 3" thick, you will want to bring in the tailstock for additional support.

Remember that the green wood fibers will be much softer and more prone to pulling away from the screw threads at higher rpm"s, so spinning mass becomes really important and the need for additional support with the tailstock.

Also, the bigger the piece, the slower you will need to start your bowl... unless you have serious thrill issues!

So, determine your equipments maximum capacities, decide what you are comfortable with relative to your chucks, etc., and remember to use the tailstock and adjust your speed as the bowls get bigger.

(Make sure teh lathe is ancored really, really well!!)

Good luck...

DW

Re: turning blank size

Wally Dickerman at Green Valley, Az.

>I teach classes at a local Woodcraft store where they have 6 Jet mini's. For bowl turning classes, we use 8 x 3 inch dry blanks. They're bandsawed round, and at a speed setting of 1200 rpm, there is little or no vibration. The first thing the students do is turn the blank into true round to eliminate any vibration. We don't use the tailstock at all. When turning hollowforms at about 5 inches in dia. we use a speed setting of 1800. I see no reason why you couldn't have blanks up to 9 1/2 inches if they are bandsawed round to keep vibration to a minimum.

Wally

Re: turning blank size

Mike Schwing from Md.

>Brad, I'd suggest when you create blanks to turn later that you also turn a few you think you might not use. By that, I mean that I used to turn only bowls, so I created bowl blanks that I could grab off the shelf when needed. But it wasn't too long after that when I started wanting to turn some enclosed and hollow forms, and I looked at a lot of my bowl blanks with a sad face, because I remember how nicely they'd have made for hollow forms at one point. Also cut some spindle orientation blanks as invariably you're going to want to turn some candlesticks, rolling pins, glue blocks, etc...

I would also recommend totally coating the blanks in anchorseal or other wax rather than just end grain. End grain only is OK for a few months (at least in my basement) but years or more will find those end grain sealed blanks full of cracks.

Also, wrap a couple in stretch plastic and they'll spalt while they're on the shelf.

Wally gave you the answer on the size, but I wanted to suggest some other things, too.

Re: turning blank size

Richard Allen

>As Wally said 9 1/2" will work fine. Remember that 10" is the swing over the bed of the lathe. If you ar making longer blanks it is the swing over the banjo that counts. So a 9 1/2" x 5" blank is likely going to require a "creative" toolrest you let you shape the blank.

A bunch of 9 1/2" x 3" blanks would be terrific turning stock when they have dried out. A hunk of wood that size is going to take years to dry. You can of course rough turn those blanks anytime and then re-coat them to shorten the drying time.

This is to say, process the blocks as you intend. The over the next few months, as time and inclination permit, rought turn and re-coat those blanks. That way you will have dry bowl blanks in less than a year.

Hove fun

Richard

Re: turning blanks

Fred in NC

>By next year this time some of mine will be ready. ugh !

I suppose putting a date on the blanks will help.

Dating

Wally Dickerman at Green Valley, Az.

>I always put a date on rough turned blanks. In 6 months I know they're dry.

Wally

Re: turning blank size

Andrew Hilton

>I max out my demo'ing Jet Mini lathe by doing large mushrooms. I cut the blanks to 9.75" in diameter by 13.5" long. This completely maxes out the lathe. Since it's so long and the diameter is so large, I have to start roughing out the mushrooms by putting the toolrest/banjo completely next to the headstock. There's just barely enough room to fit it and start roughing from that end.

Of course, your bowl blank isn't likely to be that long so you shouldn't have a problem with working on the "normal end" of the blank at 9.75" in diameter.

Thanks all

Brad in Cocoa

>My plan was to chunk the wood into rough sized blocks, coat with sealer and let sit until later this winter when I hope to have a lot more time in the shop. Yard work(2.5 acres)in Florida takes a lot of time. I picked up some red maple several months ago but did not have any anchor seal at the time and that wood is just about rotted. I wanted to stop a repeat performance.

Brad