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ribot
11th April 2006, 10:23 AM
I was just looking through a book titled "Woodturning Masterclass" and noticed that a few of the turners featured used hot air guns to dry the surface of the bowl before sanding because it makes finishing/sanding easier.
Has anyone here used this method on green timber and achieved a good result?
I am under the impression that green timber will split or crack if your sanding generates to much heat so how is a heat gun going to effect it?

Cliff Rogers
11th April 2006, 02:24 PM
Only works if the piece is very thin.

I have used compressed air to sand damp timber.

You hold the air nozzle in one hand while sanding with the other.
Direct the air under the edge of the paper as you sand.
It dries the surface & helps stop the paper from clogging.

Also works with timber that is dry the cracks very easily.
It keeps it cooler during the sanding.

Skew ChiDAMN!!
11th April 2006, 04:12 PM
I was having a chat with someone on rec.crafts.woodturning about clogged s/paper when sanding LDD treated greens and they put me onto the hair-dryer method.

I promptly ruined several blanks in a row before deciding that it's not for me... it may work well for them, but they obviously had enough time, patience and timber stock to get it right.

CameronPotter
11th April 2006, 04:51 PM
I don't know how hard it is supposed to be to dry sassafras, but I am trying a home remedy to dry a bowl I am turning.

I bought a piece of sassy - wet and only just sealed with wax. It also had a knot in it just to really test the process.

Rough turned it.

Painted it with a 50/50 ratio of metho and homebrand diswashing liquid concetrate.

So far it has not cracked or warped and it seems pretty dry.

I still need to finish it off.

I will try to remember to take a few pics and report on the progress if it works.

Cam

ribot
11th April 2006, 11:06 PM
Thanks guys, might give it a go with thin walls out of curiosity.
I guess the bowl will still distort as it dries,no ?

Cliff Rogers
11th April 2006, 11:16 PM
... I guess the bowl will still distort as it dries,no ?
Yes. :(

bdar
12th April 2006, 12:18 AM
What Cam has got with the dishwashing liquid and metho could be a winner. I know that Ron Kent in Hawaii has had good success with the same method on his Norfolk Island Pine bowls but he uses water as his mixer. Also to control the amout of blue in his logs, he freezes them at different stages and been green logs to start with, the water molecules freeze and when he turns them the water is trapped in the shavings and the rest goes through centripical force and the added bonus you are cool from the shavings.
Bdar

Skew ChiDAMN!!
12th April 2006, 02:22 AM
What Cam has got with the dishwashing liquid and metho could be a winner. I know that Ron Kent in Hawaii has had good success with the same method on his Norfolk Island Pine bowls but he uses water as his mixer.

The main difference is Cam is applying his as a paint, while Ron's LDD method is a soak. I've been trying the LDD with mixed success... but that could be 'cos his "brand" of LDD isn't available here. It certainly gets a pong up after a few loads, so I'm interested in seeing how Cam's method goes. :D

CameronPotter
12th April 2006, 09:33 AM
Checked the bowl this morning...

Still looking great!

As for the pong though, mine started pongy (metho).

I am storing it in an old acetone tin.

Cam

hughie
12th April 2006, 10:00 AM
Hi, If you want you can take the compressed air idea one step further by using a ranque hilsch vortex.
It produces below zero air temps for compressed air as well as high temps, very simple to make and very effective
http://www.southstreet.freeserve.co.uk/rhvtmatl/rhvtinfo.htm
http://www.exair.com/vortextube/vt_frmain.htm
heres a couple of links to give you an idea. A bit pricey to buy, but dead easy to make your own. If anybody is interested i will email what I have got on the subject. i have made several of them and they work fine.
Ron Kent: as far as I can see hes painting his soap on the out sides. But seeing that his vessels are only 3-4 mm thick it would work asap.
For me I soak the roughed out blanks for up to a month, then dry for about 6 weeks or so. Soft woods work best, Oz hard woods are a different kettle of fish and I have not been that successful--- 1st class firewood tho:D
Hey Skew don't think the brand is that important but he stresses his mix 1:1 with water as being important. He use the cheapest he can find.
no colour :D .
hughie