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green wood
- Thread starter ryan34
- Start date
Hey Ryan.
Welpers, any endgrain platter turned from a whole ash log is just about guaranteed to crack as it dries. The heartwood around the pith is usually a pretty distinctly different density than later heartwood and sapwood so you usually get different shrinkage rates, resulting in cracks. All I could recommend is turning it relatively thin and very consistant in thickness, then sit back and pray. You could always try stuff like boiling or alcohol soaks but not sure how well they would work. You can also try repeated soakings in eurythane oil or pentacryll to try and stabilize the wood as it dries.
Good luck,
Dietrich
Welpers, any endgrain platter turned from a whole ash log is just about guaranteed to crack as it dries. The heartwood around the pith is usually a pretty distinctly different density than later heartwood and sapwood so you usually get different shrinkage rates, resulting in cracks. All I could recommend is turning it relatively thin and very consistant in thickness, then sit back and pray. You could always try stuff like boiling or alcohol soaks but not sure how well they would work. You can also try repeated soakings in eurythane oil or pentacryll to try and stabilize the wood as it dries.
Good luck,
Dietrich
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You willing to accept distortion based on grain irregularities? If so, make your turning thin, say 3/8 to 1/4, then put it to dry where air can reach both bottom and top of the piece, rather than sitting it on a solid surface. That way you won't have some end grain protected and expanded while the rest is almost dry. Difference is what starts cracks.
Have to say that ash isn't the best for this purpose. Wood with interlocked grain like yellow birch or aspen/willow family would be better. Elm, if you can get it is almost bulletproof in drying for the same reason. Not that it can't be done, but your chances of success are increased with more favorable woods.
Alcohol won't do anything for you, and boiling is not going to help much either. Water-soluble bulking agents like the pentacryl offer the best chance.
Have to say that ash isn't the best for this purpose. Wood with interlocked grain like yellow birch or aspen/willow family would be better. Elm, if you can get it is almost bulletproof in drying for the same reason. Not that it can't be done, but your chances of success are increased with more favorable woods.
Alcohol won't do anything for you, and boiling is not going to help much either. Water-soluble bulking agents like the pentacryl offer the best chance.
Yeah, I'm with Michael. If you can use an agent that prevents it from shrinking at all you keep your best chance. The bulking and stabilizing agents work for that. You pretty much try to freeze the piece into the shape it's in before it dries.
I guess another option is to wrap the whole piece in butcher's paper when it's done and put it in a cool place. Reeeeealy slow drying can help a little in keeping the stresses minimum.
Hey Mike, what about microwaving the whole piece repeatedly to plasticize it as it dries? Will that just end up with it cracking the first time the humidity changes?
Dietrich
I guess another option is to wrap the whole piece in butcher's paper when it's done and put it in a cool place. Reeeeealy slow drying can help a little in keeping the stresses minimum.
Hey Mike, what about microwaving the whole piece repeatedly to plasticize it as it dries? Will that just end up with it cracking the first time the humidity changes?
Dietrich
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No micro for me on these. Just a few days from green to finish when it's all endgrain anyway, no sense in risking lighting a knot. Only shrink you will have to affect the shape will be where there's some long fiber. Short stuff can't get organized enough to pull apart. If I were to micro out of impatience or intent, I'd be sure to keep it in a plastic bag to limit loss and temperature.
With the home heating season in progress and the low humidity, I put similar pieces in a paper bag or wrap in newsprint, after a paper towel to keep the ink from transferring.
With the home heating season in progress and the low humidity, I put similar pieces in a paper bag or wrap in newsprint, after a paper towel to keep the ink from transferring.
john lucas
AAW Forum Expert
If you leave the heart in the log and make it flat it will split. I have dried some very small limb segments by placing them in a plastic bag and reversing the plastic bag every day. It took a very long time to dry and they all had discolored due to mold. Looked good for what I was using them for.
the only way I know to turn a slice of a log into something useful is to make a cone shaped bowl. the reason the wood splits is while it's drying the rings get smaller. The inner rings won't get as small as the outer rings and since they are all bound together something has to give.
If you turn a cone shaped bowl the outer rings will shrink and the cone will get taller and narrower at the top and will often warp. If you've made it thin enough the wood can handle this movement and won't crack.
I've never made a large piece using this technique (which I learned from Dave Barriger) but have done some experiments making goblets and it seems to work just like he said.
the only way I know to turn a slice of a log into something useful is to make a cone shaped bowl. the reason the wood splits is while it's drying the rings get smaller. The inner rings won't get as small as the outer rings and since they are all bound together something has to give.
If you turn a cone shaped bowl the outer rings will shrink and the cone will get taller and narrower at the top and will often warp. If you've made it thin enough the wood can handle this movement and won't crack.
I've never made a large piece using this technique (which I learned from Dave Barriger) but have done some experiments making goblets and it seems to work just like he said.
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Like John said the cone shape lets the wood move since the growth rings are offset by the cone.
A more general comment is that an endgrain platter will be rather fragile and not utilitarian. Even at a 1/2" thick a relatively flat platter turned engrain would be easy to break. A side grain platter is much more sturdy.
Also it is hard to make endgrain look pretty. Most cabinet makers go to great lengths to hide the endgrain.
Turned pieces have to show engrain somehwere.
Occasionaly spectacular grain patterns can be shown in an endgrain turning.
Norfolk Island pine with its ring of knots is often shown endgrain.
happy turning,
Al
A more general comment is that an endgrain platter will be rather fragile and not utilitarian. Even at a 1/2" thick a relatively flat platter turned engrain would be easy to break. A side grain platter is much more sturdy.
Also it is hard to make endgrain look pretty. Most cabinet makers go to great lengths to hide the endgrain.
Turned pieces have to show engrain somehwere.
Occasionaly spectacular grain patterns can be shown in an endgrain turning.
Norfolk Island pine with its ring of knots is often shown endgrain.
happy turning,
Al
Last edited:
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A quick review of the FPL diagrams in the wood handbook gives a better explanation, but you have to remember that all shrinkage, like politics, is local. The largest contiguous area is moved away from the largest dimension physically by hollowing. Note that on a platter you can do this on the reverse, under a rim, and get the same stress relief if you have a broad "foot" section to work with.
I've posted a couple/three endgrain pieces here in "gimme" woods like elm and birch, but they were done basically the same way, where the blank looked like a plano-concave or even double concave lens while drying, producing a platter when re-turned. Even posted a weird cherry form with two heart wings. Don't be discouraged. Not only can it be done, though at risk and with care; it can be done to produce things which do look good. At least for my eye end grain can be quite handsome.
I've posted a couple/three endgrain pieces here in "gimme" woods like elm and birch, but they were done basically the same way, where the blank looked like a plano-concave or even double concave lens while drying, producing a platter when re-turned. Even posted a weird cherry form with two heart wings. Don't be discouraged. Not only can it be done, though at risk and with care; it can be done to produce things which do look good. At least for my eye end grain can be quite handsome.
