Advice please.....

[ChrisF]

Hi all

Came across this lump today.  Think it's oak....the white bits are very rotted, the dark bits are very hard.  As you can see there are some great patterns in it.  It's about 100mm diameter.

So.....I've jumped in and fixed it to a faceplate and turned away most of the rotten.  In the usual course of events I'd now turn a tenon and reverse it to try hollowing it out.  It looks far too unstable to take a tenon and I can't see another way of mounting it.

So, any advice please?  What would you do?  Can the rotten be stabilised in any way (ca glue, resin?), is there anything else I can try?  Have I messed it up..... :-(

Any thoughts or advice most appreciated and gratefully received.

Chris

[GBF]

You could get some wood hardner and give the whole thing a good soaking.

Regards George

[Paul Hannaby]

Yes it does look like oak.

You could apply glue, sanding sealer or hardener but it won't penetrate very deep. Enough to stabilise the surface for a few cuts but not deep enough to strengthen the whole thing.

Most people that use resin for stabilising will use a vacuum chamber to draw the resin in to the wood.

[Les Symonds]

Hi Chris...people like B&Q sell Cuprinol wood hardener and I've had great success with it, specifically for hardening the white, rotten sapwood of oak. One other trick that I developed (and I'm sure many others have done it) is to make a big wooden compression chuck that your lump fits into...here's how it works.....
take a log of firewood that's about 2" more in diameter than your lump. Mount it on the lathe and turn it into a cylinder with a tenon for your chuck, to suit the biggest jaws you've got. Mount it in the chuck and hollow it out so that your lump slides inside it easily. You should now have a shape something like an empty baked-bean tin, open at one end. Take a saw and make a few saw-cuts down the edge of the baked-bean tin, put a big hose clip around the outside (you may need to join a couple together), slide your lump in and tighten the hose clips.
A note of caution....have the tail-end of the hose clip facing away from you so that it follows the clip when it's spinning, then bind it all with gaffer tape so there are no sharp edges in case you touch it whilst it's spinning.

Here's one that I made for an urn that needed lots of support to turn it.

Les

[Bryan Milham]

Chris,

What an amazing piece of timber, I can see why you want to turn it but please don't be too disappointed if it all comes to nothing.

Looking at the whiter areas, there appears to be no (I think) lignin left in the timber, holding the fibres together, it's likely to unravel like a plate of spagetti.

But if you do manage to make anything of it, please, please post it, we'd love to see it, good or bad.

[ChrisF]

Thanks guys.  I'll let it dry a while and then try the hardener.

Cheers

Chris

[The Bowler Hatted Turner]

Chris there is something else you could try, it can be dangerous so be careful. Get some wood hardener, enough to submerge the piece fully, put it in a metal bucket and warm it up, do this outside and keep away from the fumes and be careful of naked flames. Drop the piece into the bucket and remove from the heat. As the hardener cools down it will be drawn into the timber. Remove after 24hrs and drain and then leave to dry fully, probably a couple of weeks. When you turn it you will need eye protection and a mask for the fumes.

[Bryan Milham]

John, I won't ask where you learned / how you learned that one.