End grain hollow form advice needed.

[Dan Forman]

Did another one tonight out of walnut.



Is the amount left for the base on this one better? I do like to have a little room to work in for the final parting off. There is an inch and a half of tenon and waste, plus half an inch of thickness for the bottom of the form, so altogether two inches of wood. Will this cause problems? I could use a reverse jamb chuck and turn off the tenon and some of the waste to make a new tenon, which would lose about half of the current extra thickness down there.

Dan

[Dan Forman]

Good advice above for sure. Another way--I do mostly green hollow forms--is to turn the piece to 10% thickness and wax the outside and bottom and put it on the shelf. Twenty years of this has convinced me that drying from the inside only pulls the wood together. The steady rest is good advice

Robert --- By "bottom", do you mean the outside bottom or inside bottom of the form? Thanks,

Dan

[Dan Forman]

Dan good advice from all. Myself I would finish it out and soak it with a oil finish. A lot of my end grain turnings I turn to finish and then soak with antique oil. I soak to till it won't take anymore. Surprisingly most all of them don't warp much or have any problems with cracks.

Bernie --- Does that hold true when knots are present too? I did that with the other end grain forms I turned about a year ago, but they were pretty clear. I'm worried about the large knot with pith, so want to dry this one slowly.

Dan

Dan

[Brian Ashton]

Did another one tonight out of walnut.



Is the amount left for the base on this one better? I do like to have a little room to work in for the final parting off. There is an inch and a half of tenon and waste, plus half an inch of thickness for the bottom of the form, so altogether two inches of wood. Will this cause problems? I could use a reverse jamb chuck and turn off the tenon and some of the waste to make a new tenon, which would lose about half of the current extra thickness down there.

Dan

So far the shape and everything is looking good!

[Faust M. Ruggiero]

Nice form, Dan. On the first example you showed, the one with the knot, I would have turned that to finish and made that knot thin enough not to crack. Also, separating it from the tenon will help keep the knot solid. The walnut form will dry nicely. DNA soak will bring the drying time to 6 weeks or less. I bag the form for a week or two after the one day soak. Having said that, I usually have a bunch drying naturally so I can choose what I feel like finishing. I rarely rush them any more.
faust

[robert baccus]

Actually Dan, I was refering to all the wood if waxing the exterior. Bottom. tenon, everything. Might want to remove the wax later from the tenon. Let's beat this one some more--good thread. We tend to think of wood as wood but It's like women. Tough, young, old, weak, ect. Birch is a very hard, close grained strong wood--all of which mean easy to split of bust. Opposite end of the scale from Aspen, Box Elder ect. Resembles the fruitwoods in this respect which to me means all precautions. I have very little problem with split ect but I try to never hurry drying. OBTW the shape and woods are top drawer for sure. Love the tulip shape. crotchy old forester

[Thomas Canfield]

Brian,

The amount of wood on the walnut at the tenon looks much better but still gives enough for support. The sharp angle at the bottom would probably be better left with a radius clean up when you do the clean up and turn off the tenon. The sharp corners and edges usually are called stress risers and more prone to cracks forming there (same thing happens with metals). Nice looking walnut piece.

[Dan Forman]

When I took the birch piece out to pare down the waste at the bottom, I found to my chagrin that a wide crack had started already at the mouth. I had to turn off about a half inch to get rid of it, which I think was detrimental to the form, but not necessarily fatal. It made it stubbier, and the opening became wider. It had been wrapped in brown paper, then placed in a heavy paper shopping bag on the basement floor, but it obviously wasn't enough. I gave the outside a coat of Anchor Seal, and will put it back in the bag and see what happens.

Dan