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GC
31st October 2002, 11:35 PM
No, not a post on a wrong site!

I have an tree lopper friend drop logs over regular that I split into half for turning blanks.

My problem being liquid amber and some oaks split more often than not. Most other wood splits a little but not to this extent.

Is this common with this timber? What other timber splits like this and shouldn't be used? Is cutting 4 inch boards better instead of splitting the logs in half?

Regards - GC

Tim the Timber Turner
1st November 2002, 09:43 AM
Trying to dry turning blanks 4" thick is a very hit and miss afair with a high failure rate due to cracking. Even if the blank looks OK on the outside it may have internal checking.
Red Gum is very prone to this and you can't buy kiln dried Jarrah over 2" for the same reason.

Instead of all this work with a high firewood content, consider rough turning your blanks from green timber free of cracks.

For a bowl blank a good general rule is Thickness = 10% of diameter, ie a 300mm bowl should be rough turned to about 30mm thick.

After turning I keep the blanks on my bench for about 10 days so I can monitor them. If they show signs of starting to crack I will seal them with a timber sealer. In hot weather I seal them any way.

I try and do this in the cooler months. My sucess rate is over 95% and storage space is reduced dramaticaly. Store the blanks inside out of the wind.

After turning weigh and record the weight on the blank with a texta. Do this every couple of days for a while and you will start to understand how the timber dries. Drying takes from a few weeks to a few months depending on a mumber of factors.

Hollow forms I rough turn to 10 to 20mm wall thickness and seal the outside. This forces the vessel to dry from the inside and reduces surface cracking.

I belive that using this method you can recover turning blanks from any type of timber.

As a final point of interest my recent experience involved converting a tree that had been pushed over for about 6-8 weeks. The dying leaves acted like a sponge and drew off much of the free moisture in the timber. The failure rate of converting this into dry blanks was zero.

The best part of this method is that it's realy good fun turning wet timber.

I hope this is't too long winded.

Cheers

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Some days I turns thisaway, somedays I turns thataway and other days I don't turn at all.