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Dean0
12th September 2015, 01:19 AM
Am i alone with this frustration. I have them packed with ironbark and bloodwood both of which are not checking there are a few calistamon in there as well. Cardboard boxes full of sawdust.
Many tips tricks to keep the cracks under control. I am using ca at the moment


Cheers

Paul39
12th September 2015, 02:13 AM
I can't help with Aussie timber, but here are some things I have tried.

With freshly cut timber:

Rough out bowl and soak in a solution of half hand dish washing liquid and half water for two weeks, wrap in several layers of news paper and let dry for 3 - 6 months.

Rough out bowl and put under water in slow cooker overnight, wrap in news paper and let dry 3 - 6 months.

Rough out bowl and wrap in news paper and let dry 3 - 6 months.

Rough out bowl and let dry 3 - 6 months.

I also have a pile of newspaper wrapped bowls by my small 500 watt microwave and will warm them 3 - 6 minutes at full power. Early in the drying process this will make the paper soaking wet.

This works with all of the above processes except the naked bowl. The naked bowl will check and crack.

If the pith or center of the timber is in the bowl it will crack. If there is a knot from a limb in the bowl it will crack slightly or all the way to the rim.

Red oak will crack no matter what. I had a piece of clear red oak that I had cut out of a log, cut the corners off, and gouged out the inside by plunging a hand circular saw many times into the center. It dried 7 years in the house. I put it on the lathe and turned it down to about 20 mm wall thickness and left it over night. The next morning it had two cracks across the bottom. I filled them with shavings crammed in with CA and finished the bowl. It sold as quickly as the rest.

I have not yet tried soaking in polyethylene glycol (PEG).

See:

http://www.customwooddesign.com/turninggreenwood-1.html

And:

https://www.google.com/?gws_rd=ssl#q=treating+roughed+out+bowls+with+poly

Richard Raffan has said, paraphrased, "no matter what you do, some crack and some don't".

Dean0
12th September 2015, 04:08 AM
My biggest problem is the timber around them is not cracking. They are all timbers taken on the same day and turned within a two week period. There is no pith. Cracks start both sides. If just one side I would guess uneven moisture loss? The worst are 12 inch plus left to 1 inch wall thickness the trial pieces at a half to charter once have fared well. Maybe it's my thickness putting stresses on them.

There re will be someone here that can point me in the right direction I'm sure.

Thankyou for for your help. I'd like to try all your ideas. I know there is no hard and fast rule with wood but a few short cuts would be nice now and again. I tried the alcohol method recently on a couple of pieces. Seems to work ok. 3 weeks dead dry. Soft Aussie wood only or see a lot of checking.
i have quite the supply of png ebony dust to fill cracks but perfection is what I am aiming for. I know this is probably a pipe dream but I can turn 5 green bowls a day and I am stock piling to try and get out of my daily grind.

Dean0
12th September 2015, 04:10 AM
Alcohol worked especially well with banksia pods. Dried them quick smart and able to turn a mostly dry form anyway.

TrickinWood
12th September 2015, 10:57 AM
Alcohol worked especially well with banksia pods. Dried them quick smart and able to turn a mostly dry form anyway.

How do you dry with alcohol and what type ??

Cheers

Dean0
15th September 2015, 12:44 AM
How do you dry with alcohol and what type ??

Cheers

Drink a lot of it and wait 12 months, no, I used metho (denatured alcohol) green turned to 1/2-1 inch soaked for 24 hours and packed in sawdust. If not packed checking will occure badly from my experience. I have done several Aussie species including some burls. It's something I found on a U.S. Site and just had to try. Took up to 3 weeks to stabilise weight but the bowls turned have still been stable a year later. I still use it occasionally to take out boarer sap/poo. It loosens it right up so you have a nice neat hole/gap if that is what you desire. I'll put up a couple of boarer bowls in the next few weeks as time allows.

Cheers