Green spindle crack prevention

[Mark Levitski]

I have struggled with my goal to produce lamps, weed pots, and vases to hold a glass insert from green wood. You know what comes up as the obstacle--excess cracking. I take a small green log or branch and turn it rough with either a lamp auger for that or a 3/8 hole for the weed pots or a larger hole slightly smaller than my glass insert. I've tried paper bags, which work well for all of my bowl/hf stuff. But the bulk of the wood left in these other pieces is too much to survive the drying process w/o excessive cracking. Sure, I can get away with some inlay for cracks, but I turn to sell and that trick would not work after a certain number of pieces to produce. I have recently constructed a DNA submersion bath as an experiment, yet to be proven for this application. I would really like to find a way through this because I can make some beautiful pieces with burls and leaving the bark on (NE spindle work) to just jettison the idea. Any of you braintrust woodturners have suggestions (don't bother w/ the microwaving thing--too cumbersome for my production)?

Thanks............Mark

[David E Keller]

Other than a kiln, I can't think of any way to single turn green wood this way without cracking. Coating the outside with anchorseal and twice turning would be an option to slow the drying on the outside of the piece. Likewise, wrapping the outside with kling wrap would be something to try. As you know, the problem is that the outer portion of the form is drying faster than the inside... If the DNA doesnt work, I'd try different ways to slow the drying on the outside of the piece.

[Jamie Donaldson]

When turning the entire round of a limb or small tree trunk, cracking will be an ever present possibility. The only solution that I have found to work in most cases was to drill out the pith area from the bottom, a bit size of about 3/8" for most applications.

[Faust M. Ruggiero]

Mark,
I guarantee you will not like this answer but it is the only way to make thick spindle blanks that won't crack. Buy 8/4 kiln dried stock and glue it up. Do a superior job of face jointing the pieces and the lamp, or bedpost will still look good and you won't lose your hard work to something you can't control. If grain or wood specie isn't particularly important, you can buy basswood in very thick dimensions. I've bought it for carving blanks as thick as 16/4.

faust

[Carl Civitella]

It is best to laminate the wood in lamps, however i did a lamp from a cedar post by cutting it down the middle on the band saw and then ran it through a planer to make both sides even and flat. Then i cut a 1/2 inch wide grove by 1/4 inch deep on each inside center part for a hollow wire rod. Then carefully glued the two together, hopefully stopping any movement. Lining up the grain and having a perfect glue line. I cannot tell where the glue line is once it was turned. I think you can do the same with a burl and never know it was in two parts. I know you want to drill the hole on a log and have a rustic lamp. I have had good luck with sturdy standing dead trees before decay hits them, very hard wood, perhaps you can seek them out to use. Carl

[Ted Calver]

Mark,
I am going through the same process. I was free styling on a punky sweet gum log last week and decided to try a lamp as an experiment. It's about 8"d x 24"h. I drilled the pith out with a 1" forstner for all but the last six inches of the neck where I switched to 1/2", then I DNA'd it for a couple of days and wrapped it in a bunch of newspaper. Right now it's sitting on the garage floor, but I'm thinking of putting it in my attic which gets up to 120f on a warm day. I'll let you know what happens. I don't think it will be dry anytime soon, but with punky wood you never can tell.

227576227577227578

[robert baccus]

I do a lot of vases/weedpots. i find like Keller that if you wax the outside and lip that it actually draws the wood and return of course. bore the inside and let it do the drying--goes fast for drying. i lose very few like this.-------------just my experience---old forester

[Dale Miner]

Have you tried boiling?

[Bob Bergstrom]

We've had a local guy who has made white birch lamps for years. He uses a low pressure compressor to force air down a drilled hole. An aquarium compressor would work. I am not sure if it eliminated the cracking but it did reduce the occurrence. It did reduce the drying time. He has been making white birch lamps for 30 years and I'm sure he has a number of tricks.

[Mark Levitski]

Thanks for all the suggestions. I know eliminating cracks is not possible, but since I have no apprenticeship I thought I could be missing an important tip or two re: this. No, Dale, I have not tried boiling and probably won't. I would be doing quite a number of pieces and would need to factor in setting up a fish boiler, the propane expense, and the time to babysit the process. I am getting faster, but turning these pieces takes enough time for what price I can put on them. Also, I'm not so sure that bark would withstand it. At least with DNA (IF it works) I can just dunk it and forget it. Ted, I suspect it takes longer in submersion than a couple days though, which works just fine for me. Please check back in w/ results, as will I. Bob, I'll try to experiment with forced air, but sounds too complex for production, though your birch lamp guymust fall into that category. Yes, definitely an already dry standing tree works best, and although I have my own 45 acre woodlot and am also surrounded by thousands of acres of timberlands, there really aren't too many ideal dead specimens that I've found. We have a lot of smaller cherry burled trees just the right size for pots, vases, etc. They are green. The dead ones are usually too far gone to bother with. Segmented--fo-get-it :) Not my forte, and agian, don't think I could make it work for my production.

Here's an example of some pieces:227630