Dealing with rotton sections

[howlingbaboon]

I've found recently, while half way through a few pieces, that I've encountered sections of rot. One was a piece of Beech (the vase from the other half finished up really nice) the other was a nightmare  a bit of Eucalyptus which warped faster than I could get it round again. I've tried my best to take fine slicing cuts to prevent tear out (in the right direction) and have tried with scraper. Nothing worked though, It just tore off in chunks. Are there any good tips you good folk might have? Is there a way to slice it cleanly? Is it a case of filling the holes? Maybe just a lesson in giving up and starting again with another log. Firewood?

[Bryan Milham]

I'd say the beech was just bad luck, it happens sometimes.

The 'Eucalyptus warped faster than you could get it round', welcome to Euc!

[bodrighywood]

Eucalyptus, UK stuff, is only good for surrealist turning. E.G. if ylou are quick enoiugh to actually get something finished then leave over noght you will end up with something that Salvador Dali would be proud of. Some 'rotten' wood can produce really nice effects but often it will just fall apart and break up as you turn. Best forgotten and left for the fire.

Pete

[howlingbaboon]

Yeah one of my Eucalyptus attempts did explode on me. Half of it went over my shoulder and landed an impressive 5m from the lathe! Good job the potters weren't in!

[Les Symonds]

I'm wondering exactly what you mean by "rotten"....if the wood is so soft that you can dig a finger into it, then the finished article is not going to be much use, so like Pete says, forget it. However, if the wood is reasonably dry and just has very soft/punky areas, there are things that you can do to turn it. There's a number of fluids that dry fairly rapidly and bind the wood fibres together in such a way that they can be turned. Cellulose sanding sealer, melemine lacquer, CA adhesive all work well to some degree. What I favour is a proprietary treatment for dry rot in window and door frames, companies like Cuprinol are the best to go for. Paint the fluid over the punky wood fibres and this stuff soaks in to several millimeters depth, saturating the fibres and then drying rapidly, hardening the fibres as it dries.It won't give you perfectly structured timber, but it does make an impressive difference.
As for which tools cut best on this sort of timber; I favour a freshly sharpened gouge with a light paring cut if possible (handle low down and using the wing of the gouge) on the outsides of bowls. On the inside of a bowl, it really is a case of trial and error!
Les

[fuzzyturns]

Everything that Les (gwyntog) said is valid and stands. You need to judge this carefully, though. I bought a bowl blank a while back, very nicely spalted beech. When turning, I realized that this was borderline, the wood was so soft that any sanding instantly deformed the shape. I gave it a first treatment with CA, but that didn't go deep enough, so I resorted to the same product that Les mentioned (it's basically an epoxy, a 2 component solution for hardening of wood). This penetrates quite deep into the wood.
However, the problem now is if you get anywhere near the boundary between the hardened material and original soft material, any cuts with a gouge will rip complete pieces out of the wood. And don't even think about scrapers.
I've basically given up on this piece, even though the figure of the spalting is quite extraordinary. Might have to keep it in a special trophy cabinet.

[bodrighywood]

It can also depend what you are making. If it is spindle work a skew can sometimes cut the wood cleanly if it is kept sharp. Something like a vase or hollow form it is debatable whether it is really worth the work.
Pete

[The Bowler Hatted Turner]

Fuzzy I could be wrong but I think the stuff Les was on about does not need any mixing. Designed to harden wood that is rotting away all you need do is soak it and leave it to dry. I used some on virtually rotten Oak, you know that stuff that you would not normally bother with but because you have it you have to use it!  They were pen blanks (I don't make many pens at all) so I filled a kilner jar with this stuff and dropped the blanks in. They took about 3 hours to stop bubbling and then I took them out and let them dry. The wood was really solid and turned a dream.

[howlingbaboon]

Thanks for all the advice guys! Anyone have a link to the hardening stuff that was mentioned? I'm guessing you'd need quite a lot of it to soak large bowls unless it dilutes. Do you know anything about the toxicity of these treatments.

[fuzzyturns]

This is where I got my stuff from:
http://www.epoxy-info.co.uk/resins_shop.htm#Ultrathin

[howlingbaboon]

OK so here's the result of my terrible time-wasting with Eucalyptus.    I was warned but I just won't be told! When people say it warps and literally tears itself apart, they're not joking eh! On the upshot though, my 4 large Alder bowls have dried out nicely with just a few tiny cracks in small side-branch knots which I guess can just be filled. Now I just need to be well enough to get down the workshop...

[bodrighywood]

Bit of sanding and you will have a couple of pieces that people will ask 'How did you make that? Seen worse looking things in art galleries for a small fortune LOL.

Pete

[Bryan Milham]

Euc, we all have to learn the hard way. One thing I've never worked out, in Aus there are many types of Euc and most are turnable, so why do we only have the firewood version growing in the UK?

[howlingbaboon]

Maybe it's more to do with the climate and growing conditions? There's a lot of it in California, we'll have to find out how they fair.