Help needed with drying.

[Brian McInturff]

I had cut some blanks from a downed oak the other day. They still had some moisture in them but weren't real wet. I turned a nicely shaped bowl 3/8th wall on side and was letting it dry before doing final turning. It's starting to seperate a little with the grain at the top ridge. Being new to turning a more green type wood is there anything I can do to prevent it from seperating more. I have it in a bag of shavings right now. Could I coat it with Anchorseal to prevent anymore seperation? Bake it at 200 in the oven wrapped in aluminum foil with the top open for evaporation? I've turned a few other pieces out of this but left the pieces much thicker and haven't seen any checking, splitting, or seperation. The pieces are highly spalted and I really don't know how long they have been down. It definitely didn't cut like "green wood". I hope to post pics when I can figure out how to download them off my Razor phone without having to buy yet another program(you can't just download them into photoshop). Thanks, Brian

 

[Matt Meadows]

If this bowl is a finished product (final turned or sanded or finished) your best bet, my opinion, is to keep it somewhere moist and cool for a month or three (depending on how anal you want to be about it). The change the situation--- remove the shavings and leave only the paper bag, or move it all to a warm dry place (with shavings) for a month. Then out in the open on display to see what happens.

If I sound like I'm saying "just experiment carefully", that's IT!

BUT....

If this piece can be re-chucked, returned (down to around 3/16th thickness), then FIRST soak the whole thing overnight in denatured alcohol or methanol (methanol is toxic, be careful.... but it is 1/3 the cost). Then put it in a paper bag in your home for a week and then out in the open for another (i'd make it two weeks each step if this was a thicker, wetter bowl than you have). Re-chuck and finish turn it. Should be good to go.

 

[Brian McInturff]

Methanol, hmm, I've got plenty of it from work that we don't use any more. Will Isopropynol work also? Thanks, Brian

 

[Ron Sardo]

Methanol, hmm, I've got plenty of it from work that we don't use any more. Will Isopropynol work also? Thanks, Brian

Household Isopropynol has to much water so it wouldn't work very well. For more info click on this Alcohol Soaking and follow the thread

Most times turners will turn a green bowl so the thickness is 10% of the bowl diameter, seal the endgrain, then wait a few months. Rechuck and finish turning the bowl.

Other times turners will do exactly what you did, because they want it to warp and crack and then they call it art.

 

[Brian McInturff]

Nope, not household grage but Pesticide grade. I do environmental work and use it and methanol all the time. Since we can't store it in the office I get what's left after a job. I think I try it and see what happens. Brian

 

[pyrocasto]

There is also boiling. I've never played with Oak yet which I hear is a pain to dry, but it has worked on everything else nicely. The wood warps just the same but zero cracks yet.

 

[MichaelMouse]

Oak is just being oak. It has no choice, really. The radial checking you're seeing now was, in all probability there when you started, but may have closed by recent uptake of moisture. Really common thing to happen with woods stored or standing dead.

Then there's the ray pattern in oak and other similar woods, designed for carrying water across the grain. It's also a built-in weak spot, as those of us who split the stuff for the furnace can tell you, so drying stress like the radial tug that opens your edge or the combined radial/tangential that opens on the ray figure on the outside of the bowl acts easily on it.

Alcohol won't do much of anything, but if you close it with higher humidity and then run some water-thin CA into the crack you might hold it. Of course, by creating a strong spot, you might force the wood to find another weak one near by.

Boiling is not going to do much once the opening is made that cold water won't. Boiling makes the wood plastic, which might relieve growing stresses with a bit of fiber slide, but can't do much to stop the shrinkage caused by loss of bound water, which is what you're observing. That depends primarily on the orientation, interval, and relative density of the annual rings, and secondarily on the shape of the piece itself.