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Jim Becker
12-12-2004, 9:03 PM
...and sometimes the bear bites you. So I decide it's high time to do a little spinny work for a change. I needed an ornament for the local chapter meeting Pollyanna next week, so I grabbed a cutoff of mahogany and played around a bit before coming up with the nice donut shape shown below. Worked out nicely and gave me an opportunity to see how "gentle" my Talon chuck could be as I cut out the "donut hole"...suprisingly gentle, I'll add...minimal sanding on the edge was needed to complete the project. This piece is about 2.75" in diameter. Finish is just wax.:)

Ok, that worked out, so lets put this nice big hunk of spalted Norway Maple on the lathe and do a big and tall bowl in one of my favorite sweeping shapes. Wonderful. The profile was exactly what I wanted and with some shear cutting techniques I was able to get a nice smooth ready to sand and finish on the outer profile. Hollowing started out great, but about 2/3 of the way down I discovered that in my exuberance at being on the lathe after a long hiatus, I failed to follow the outside profile, despite working in steps and checking thickness in my usually non-scientific way...with my fingers. Oops! We now have a substantially shorter bowl. :o Sheesh!! At any rate, one must play with the hand dealt, so the smaller bowl was constructed out the the portion remaining on the chuck and the larger portion (which is perfectly round and quite stable) will be used for something unique in the future. The bowl is about 6" in diameter.

Such is life in the spinny lane... :rolleyes: ...but is was fun despite the "design change" along the way.

Mark Singer
12-12-2004, 9:17 PM
Jim,

Just remember if you have any questions about turning...don't be shy

Things are turning upside down...You know how much I know about it:mad:

Nice work...maybe you don't need my advise

Bruce Shiverdecker
12-12-2004, 10:21 PM
Hey Jim, Did you have a hand on my hollowing tool, when I was cleaning out the inside of a piece of Crab Apple?

It started out as a natural edge 6' ball with some neat holes. OOPS......... evening out the inside 1/4" thick..............Bang! Now it's 4" tall.............Still needs to be to be evened out. Very GENTLY this time.

Daggone Rotten Ratsinfrats!

It's finished................................1-1/2" tall & 4" dia at top!

Oh well, I guess that that's what it wanted to be!

Bruce ;)

Kenneth George
12-12-2004, 10:25 PM
I really like the ornament! More my size of turning. The bowl is very pretty also though.

John Miliunas
12-12-2004, 10:32 PM
...and sometimes the bear bites you. So I decide it's high time to do a little spinny work for a change. I needed an ornament for the local chapter meeting Pollyanna next week, so I grabbed a cutoff of mahogany and played around a bit before coming up with the nice donut shape shown below. Worked out nicely and gave me an opportunity to see how "gentle" my Talon chuck could be as I cut out the "donut hole"...suprisingly gentle, I'll add...minimal sanding on the edge was needed to complete the project. This piece is about 2.75" in diameter. Finish is just wax.:)

Ok, that worked out, so lets put this nice big hunk of spalted Norway Maple on the lathe and do a big and tall bowl in one of my favorite sweeping shapes. Wonderful. The profile was exactly what I wanted and with some shear cutting techniques I was able to get a nice smooth ready to sand and finish on the outer profile. Hollowing started out great, but about 2/3 of the way down I discovered that in my exuberance at being on the lathe after a long hiatus, I failed to follow the outside profile, despite working in steps and checking thickness in my usually non-scientific way...with my fingers. Oops! We now have a substantially shorter bowl. :o Sheesh!! At any rate, one must play with the hand dealt, so the smaller bowl was constructed out the the portion remaining on the chuck and the larger portion (which is perfectly round and quite stable) will be used for something unique in the future. The bowl is about 6" in diameter.

Such is life in the spinny lane... :rolleyes: ...but is was fun despite the "design change" along the way.

What's a "spinny thing"??? :confused: I think you did just fine on both pieces, Jim. One of these years, I may find out if either of my lathes work anymore! Heck, following along with Mark, they may just as well be upside down, too! :) :cool:

Michael Stafford
12-13-2004, 6:51 AM
Jim, no one would have ever known had you not spilled the beans. On purpose or by accident your work exceeds my expectations all the time. It is reassuring to hear that I am not the only one that has to make design changes in mid stream...

John Shuk
12-13-2004, 7:07 AM
Jim both are nice work.
I need to get a handle on your finishing regime though I think the finish on that norway maple is outstanding. The reason I love the lathe is that I can make a mistake and not have to give up on a piece. It might get smaller as often happens but I usually get something. You got something really nice and I like the shape of the bowl too.

Jim Becker
12-13-2004, 9:10 AM
I need to get a handle on your finishing regime though I think the finish on that norway maple is outstanding.LOL!! 'Hate to tell you, John...but that's just wax. I was in no mood whatsoever to deal with anything else at the time. Honestly, I've used "just wax" on a number of turnings, particularly Norway Maple and Ambrosia Maple and it pretty much does not alter the color noticably. As long as the piece is decorative...no big deal. This whole thing about "protection" in woodworking, particularly for decorative items is a bunch of hooey, IMHO. So many folks spend a lot of time layering gallons of stuff on their work when something simple, such as a buffed oil-varnish or just wax would do a nice job. There certainly is no need for "poly" on anything like this!!

Jack Hogoboom
12-13-2004, 7:15 PM
Jim,

Can you explain how you managed to chuck your donut? I'm having trouble picturing how you did it.

My Talon gives me fits. Seems like nothing will run true on the chuck and I've broken a few tenons in the learning process. Undoubtedly operator error, but I'm hoping to improve.

Reverse chucking bowls has proven to be a big frustration for me....

Jack

Jim Becker
12-13-2004, 7:37 PM
Can you explain how you managed to chuck your donut? I'm having trouble picturing how you did it.I started the piece by putting the blank on a glue block to true and put a radius on one side followed by parting it off. It was then reversed on to a vacuum chuck and the opposite side radiused. Having a nice "hole-less donut", I put the #3 jaws on the chuck and just put the round object in the jaws, bottomed out and resonably square and then I carefully developed the "donut hole" using a small gouge. I only tightened the chuck enough to securely hold the piece and it was sized such that the #3 jaws gripped it most of the way around without over tightening. (honestly, that was a lucky guess!) Once the hole was cut from one side, I reversed it again to refine that side.

In other words...I was just playing! :D


Reverse chucking bowls has proven to be a big frustration for me....I start out between centers and develop the outside profile of the object and put a tenon on it at the tailstock end. For a larger object you can use a faceplate or screw chuck, but should still use the tailstock for security. At that point the outside should be pretty much what you want it to be other than a little refining of the foot to remove the tenon, etc., later on. Reverse onto the chuck. It "should" run true, but you may need to work a little to get it that way if it's not coming up right. Being sure to turn a small shoulder outside your tenon for the jaws to seat on is very important to this as well as to avoiding breaking off a tenon. You NEED that support, especially as the size of your turnings increases.

BTW, as you know, this is a little different than the way your turned at David's since he has you (presumably he still does, at least) prepare your blank between centers to attach a larger faceplate with screws. You then turn the form, leaving material at the bottom 1/3 of the piece to refine after you hollow. The larger faceplate allows you to visualize the bottom of the bowl (at least you're supposed to visualize it that way!!) inside the ring of screws and you necessarily judge the interior depth taking that ultimate bottom in consideration since you can't exactly measure it quite the same way as other methods.

In either case, there is a need to do a final reversing of the bowl to finish the bottom. David teaches using a jam chuck method that keeps the tail stock in play. Simple. Inexpensive. And with the custom "parting gouge" made from the reground spindle gouge, you can leave almost no hand work work on the bottom. Personally, I much prefer my vacuum chuck for this when it is usable, but many turning require David's method or similar when there are inclusions or other reasons you can't hold a vacuum. But if my vacuum pump died tomorrow...I could still finish bottoms nicely using the more traditional method with no problem.

If you need some additional help with this, make arrangements to come down for a visit some weekend after the first of the year.

Jack Hogoboom
12-13-2004, 9:33 PM
Jim,

Thanks for the tips. I've been trying to follow David's method, but I have problems visualizing that bottom third of the bowl and getting deep enough into the side to get a decent shape. Just more practice I guess.

The chuck works OK, but in my hands it mars the tenon or else the tenon snaps off (I assume that has something to do with my hollowing technique). I tried expanding the jaws into one bowl and promptly wrecked the bottom.

I'd like to try Bill's compression chuck sometime. Maybe that will work better.

In any event, I can always go back to David for more lessons.

Jack

Jim Becker
12-13-2004, 11:08 PM
Maring the tenon shouldn't matter...it's just going to be cut off later anyway...isn't it? If your design includes keeping the tenon, you still need to plan on "dressing" it after reversing since you need to crank that chuck down to have holding power and that will mark the wood. Do try and plan for a little visit and I'll help you with a few of these things...