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TTIT
2nd January 2006, 12:43 AM
I'm always reading about burying your roughed out articles in shavings for a while but nobody ever says WHY!:confused:

Is it ...

(a) to speed up seasoning?
(b) to slow down seasoning?
(c) to induce spalting?
(d) a memory test? ("I know I started a she-oak bowl once but where...")
(e) a senility test? ("Mummy, why does Poppy hide things from himself?")

Someone please help me out here. It gets so damned hot and dry out here that I need to slow or balance the drying process. Everything dries out too quick so cracking is a major problem. We started hitting 40C in spring this year and I lost a heap of timber that I had just end-sealed and stored. I even fitted an evaporative air-con to the shed during the winter so at least I'll be able to keep turning this summer instead of running for cover like other years.

beiffe
2nd January 2006, 10:10 AM
I used to have old fridges laying on their backs when I lived in NSW. I filled these with old shavings and then buried my green turnings in these shavings.

I lost a few, but very few and it was hot out there and they were in a small shed ( old chook house actually put to better use).

If I had something extra green then I tried to get the shavings from the turning and made a bed of these green turninge and buried the new work in them. I felt this then used the moisture form the green chips to slow drying down and gave the turning time to start slowly.

To encourage spalting I leave timber end down on a cold wet concrete floor somewhere and leave it for a few monthe then turn for the other end. Works a treat on the ones I have tried but only use it on timber I would normally not worry about turning as it is too dull etc.

ptc
2nd January 2006, 10:14 AM
Get the dry stuff.
there's got be some around you area.
try sapphire or anakie.
gidgee etc.

scooter
2nd January 2006, 10:47 AM
TT, the impression I get is that it's to slow down the drying process to hopefully prevent splitting.

Not sure, but I seem to also recall a mention of putting roughed out blank & shavings/sawdust in a plastic bag, once again to slow the release of MC of the workpiece. Wouldn't want to be too wet, though, for obvious reasons, would be inclined to mould/spalt (same thing?).

Sawdust would be better I'd have thought, be able to pack it denser around the workpiece and would have a better insulating effect.

Keep putting these threads up, mate, good to discuss fundamentals like these to edjakate non-turners (yet!) like meself.


Cheers....................Sean

Baz
2nd January 2006, 04:40 PM
It helps to slow down the drying process so that the sudden loss of moisture doesn't cause the cells in the timber to collapse. You could also try coating the roughed out bowl in end grain sealer, I usually do that for red gum burl.
Cheers
Barry

TTIT
3rd January 2006, 12:25 AM
Thanks for the pointers guy's. I've lost a couple of nice bits of wood by leaving them on the lathe overnight with just the outside turned (often don't get started til 9 or 10 at night) - from now on I'll slip a plastic bag over them until I can get back to them and see how it goes. Once I've roughed them out, I'll try shoving them in my 20 gallon vacuum drums that are waiting to be emptied - could be just the trick - providing I remember to remove said turnings before the next tip run!:)

Skew ChiDAMN!!
3rd January 2006, 12:50 AM
In my opinion, storing in sawdust is really more useful for the production turner or when you're turning a large "set" of something.

Basically, it lets you do some green turning, then put the piece aside for a while before coming back to it, without having to worry overly much about splitting in the time between.

Personally I haven't found it a reliable method for fully curing the wood, less reliable than coating the rough-turned item in end-sealer. It does make storage easier if I pack the item in it's own shavings in a card-board box though... it also gives me somewhere to write important info. ;) I don't often do this though. [shrug]

I don't put sawdust in plastic bags that promotes fungal growth. 'Tis fine if you want spalting, but even then it's a hit'n'miss affair whether the end results usable. Otherwise... no plastic bags. DAMHIKT. :o

rsser
4th January 2006, 06:25 PM
Timber species vary in their propensity to check or crack while drying. Best thing is to try one method but check regularly in the beginning and close up or open up accordingly. Ordinary Tas Myrtle eg. is very unstable.

Raffan tosses all his green rough-turned pieces into a cardboard box, rotating and checking from time to time.

Darrell Feltmate
4th January 2006, 10:55 PM
The reason to put the rough turned bowls in shavings is to even out the water loss between end grain and side grain as well as the loss at the inside and outside of the bowl. Incredible as it may seem, there is a more rapid water loss from the outside even though the rough-out is only an inch or so thick. Methods for slowing down the loss rate vary.
1) pack the bowl in green shavings, lots of shavings
2) soak in a vat of alcohol
3) soak in liquid dishwahing detergent (another topic in its own right)
4) boil for an hour to the inch thickness
5) apply Anchorseal or similar to the end grain
6) do nothing and hope for the best
Personally I use the Anchorseal but I am in a significantly different climate. Of the hundred or so bowls and blanks here drying, they all seem to be doing reasonably well. O, by the way, if you have to leave a piece on the lather longer than a few minutes, wrap a plastic bag around it. Rapid drying on those still thick walls combined with the new attempts to relieve stress after initial cuts will crack wood quickly.
There is more information on my website under roughing out bowls www.aroundthewoods.com (http://www.aroundthewoods.com)