Hollow forms - do you twice turn them?

[Jake Helmboldt]

So when turning hollow forms do you rough out the blank and let it dry (with extra thickness) as is the case with bowls? It seems a little dicey compared to bowls with the potential for catches, especially when hollowing with freehand tools.

If you do twice-turn, does the 10% of diameter=thickness rule still work?

thanks

[Steve Schlumpf]

That's how I do it... rough out to 10%, dry and then finish turn.

[Bernie Weishapl]

Jake I think a lot of them do leave green vases at 10% and then leave to dry. I did one a few years ago that I left at 10% and soaked in DNA. I let it dry for several months. After that one I now turn all of mine to final finish in one setting. I would much rather turn green to finish than to finish a dried piece.

[Fred Belknap]

I do like Steve, I hate it when they warp.

[Alan Trout]

I do all dry stuff so no I turn to finish thickness.

Alan

[Baxter Smith]

Either way. Almost all the wood I turn is green to start with. If I want to add fitted pieces to it, lids, finials, or pedestals, its 10% then returned. If its going to be a single piece form, where a little change of shape doesn't really matter and hardly be noticed, it can be turned thin. You do need to make some provision or plan for flattening the base after it drys so it will sit flat.

[Scott Hackler]

I have been making a bunch of smaller HF lately and I have been turning then green to finial thickness, sanding to at least 320, coating them with either BLO or thinned shellac and letting them dry out and finish them. The tenons are gone before I coat them for drying. This is working pretty well, but I have been turning some very dense / hard wood.

[Bill Boehme]

I'm with Bernie, Baxter, and Scott. After all, hollowforms are end gain turnings and, therefore, warping is not going to be nearly as significant as it is with cross-grain turning. There are some woods like white oak and hickory that can be hollowed easily when green and beat you to death when dry.

[Scott Hackler]

Bill, I don't limit myself to turning end grain for hollow forms. In fact the last two Sissoo HFs I just turned from the latest "gift" from Kathy, were turned side grain. I don't like to "play by the rules"! :)

[John Keeton]

I turn only dry wood for HFs, and most of mine are turned side/face grain. The one side grain wet HF I turned (and re-turned) had way too much movement for me to end up with the size entry hole I wanted. A little warp can make a big difference in a small turning.

[Jack Mincey]

I like to return most of my HF's so that they don't look warped especially around the opening. I do turn a few to finish thickness green when they are to have a bark edge opening like this one.
Jack
http://img.photobucket.com/albums/v727/flyrod444/IMG_3298.jpg

[Dennis Ford]

Most of the HFs that I turn are turned from green wood to final thickness and are side grain. They do warp and I think that gives them more of an organic character. If the piece will have a finial and/or a pedestal then I will rough it and turn it again after drying. The 10% rule works well for side grain, for end grain oriented forms you don't need that much thickness for twice turning.

[Rick Markham]

I don't generally turn green wood, but when I have it was super thin to allow it to warp. I'm interested in this thread because I just got some spectacular BLM burl that is green and waxed, and I'm not sure if I can wait to turn it :)

[Joe Landon]

I turn green wood to final thickness.

[David E Keller]

I go green to final thickness for stand alone pieces, and I twice turn when planning for a lid/collar/finial. The 10% rule seems to work for me. I generally paint the outside of the form with anchorseal and put them on a rack upside down to dry.

[charlie knighton]

i turn green or dry hf blanks to final thickness, i turn mainly endgrain, if i want to put a finial on it i turn mesquite

[Steve Braman]

Can you hit only the outside the second time around, or does it feel all wonky and unbalanced that way? I was thinking that I might finish turn the inside except near the mouth while green and hit this area plus the outside once dry. Is this asking for trouble? Having not hollowed before, I thought it would be easier to finish the majority of the inside while green.

[David E Keller]

I return both inside and outside if I do it in stages... It's not too bad having another go at the inside.

[Bill Boehme]

I forgot to mention that I mostly turn mesquite so warping would not be a significant issue anyway. Green mesquite turns very nicely and dry mesquite ... uh, doesn't. I don't pass up the opportunity to turn any good free wood and I do like to turn figured maple, but it does not grow on trees around here so I have to resort to the un-free variety. I guess that I won't call the HF police on anybody for turning side grain.:D Since most mesquite is not especially large diameter, I generally associate HF turning with end grain. Since I have not tried it, I am just wondering how easy or difficult is it to use the hollowing scrapers (or spindle tools for chalice and goblet type HF's) when doing side grain HF turning.

[Bill Boehme]

Can you hit only the outside the second time around, or does it feel all wonky and unbalanced that way? I was thinking that I might finish turn the inside except near the mouth while green and hit this area plus the outside once dry. Is this asking for trouble? Having not hollowed before, I thought it would be easier to finish the majority of the inside while green.

If it is thin then, no. If it is thick then it is a judgement call. If the uneven thickness doesn't bother you then it won't bother anybody else.

If the warping is really bad and you do not have enough thickness to turn the entire exterior down to where you are no longer turning air then maybe it would be best to leave things alone.

[Mark Levitski]

I don't do many endgrain HF's, Bill. But the facegrain is, for me, easy to do with traditional hollowing scrapers. Not much experience to comment re: spindle tools. If I can do it, anyone can.

Back on topic--I turn mostly green HF's and let them warp. They are thin enough to not move unduly upon drying. I do not however do many lids or other inserts. You would want stabilized wood for that (dried).

[BILL DONAHUE]

On the last few hollowed forms I've tried rough turning and then soaking them for a day or so in a 50/50 mix of liquid dishwashing detergent and water as described on the excellent website of Ron Kent. The results are fantastic with little to no warping and the pieces are ready to finish turn in a day or two. It also makes the turning go very smooth even on wood that is normally difficult to turn (dry norfold island pine). The unexpected benefit is that your hands get soft and smell good. I'm just finishing three norfolk pine pieces this way, two were as dry as a bone and the other green, and will post pics within a week.