Help with spalted wood

[smartecosse]

So, the tool rest for my "new" jubilee lathe turned up and I thought I'd have a go turning a bowl with it............there was a lump of spalted wood that the chap I got it off had been kind enough to include along with a few other bits so onto the lathe it went.

However, being a beginner to turning and never having turned this type of wood before I am unsure as to what to do with the sort of soft pitted areas that are present in a few areas....

Do I just leave it like it is, or fill it with something and then finish the bowl?

Thanks for any advice.....

 

[Brianp]

You could fill with contrasting (or not...) wood dust, or coffee grounds, and CA glue, then sand to finish. Alternatively, if it's tear out, then (assuming your tools are nice and sharp) use sanding sealer to help stabilise the punky areas before doing a final finishing cut and seeing if you're happier with that. I haven't turned much of spalted beech, but that sort of thing seems to be par for the course.

 

[Glynne]

As Brianp suggests or your could use a proprietary wood hardener e.g. Ronseal.
I'm guessing you are using dust protection anyway but spalted wood can be really bad for you as the dormant spores which cause the spalting can get re-activated by the moisture in your lungs.

 

[CHJ]

When nearing finished size soak everything well in sanding sealer, can be some advantage in thinning it about 10% with thinners to encourage it to soak well into the wood, multiple coats until the softer areas stop accepting it, remember all spalted wood is in a stage of rot so can really benefit from being stabilised with a hardener as far as finish and withstanding future knocks.

Don't want to discourage you from experimenting with various spalted samples, it's the only way you will learn the How, Why and When of handling it, but be prepared to accept that at some stage in your experience curve you will put a piece on the lathe and quickly make the decision to consign it to the firewood pile, even if it's not to expose yourself to the hours of frustration rather than it not being fit for final purpose if enough time and expenditure is spent on it.

AND take heed of the dust warnings, growing mushrooms in the lungs is not a profitable enterprise.

 

[KimG]

While the advice about dust protection is very valid and should be followed thoroughly, it should be said that there are no spores in spalted wood (at least, no spores from the fungus that caused the spalting) Spores are entirely a product of the fungus fruit body, the actual mushroom, toadstool (or mainly, though by no means always, in the case of wood) bracket fungus. The spores are produced in the gills, or in some fungi, small holes in a sponge like mass where gills would otherwise be found, any fungus produces millions of these from the fruit body, usually within a few days or a week or so after growing to maturity, the spores are incredibly tiny, requiring a microscope to see them. Hence they are very light in weight and are wind and air distributed, at any time then, the air you are actually breathing now is quite likely to have spores from fungus anywhere in the world, the spores are carried enormous distances and remain viable for long periods, however, they require very specific conditions before they can begin to grow into a fungi again, hence, despite the large distribution of the spores, the fungi remain roughly confined to those areas and climates that suit each particular type.

The black lines and white areas as well as any colours in spalted wood are caused by different fungi establishing a boundary from a neighboring fungal growth, these growths are in fact the true fungus, called the mycelium, a sort of root or mesh like structure that is actively breaking down the wood and using it as an energy source, the fruit bodys, like any fruit, are the means of reproducing, and are the external and visible part of the organism. Thus, no spores are in the wood itself.

However, the caveat about dust is still totally relevant.

this video by Seri Robinson has much interesting info on spalting too.

 

[jurriaan]

If this is the first spalted wood you have, I can understand your reluctance to let it go, but that would be what I would do: just get it off and use it for firewood. In the words of Mike Tingey 'Don't worry, it's only firewood'.

There's hard spalted wood with an occasional soft spot, which is good to turn, and there is wood that's mostly gone and requires copious amounts of chemicals to get it anywhere near finished, and even then, will in my opionion never look as good as I'd like.

 

[Dalboy]

Looking at that piece I would not advised you to try to turn it without some other turning under your belt. As said above it need stabilising quite a bit before going any further.
I now would remove this from the lathe and turn some solid wood for a while until you have honed your turning skills like tool handling and getting the feel for the wood.
Not what you may want to hear but you could end up very frustrated trying to continue with this one.

I personally enjoy turning spalted wood when I can get hold of it.

 

[Robbo3]

Swamp it in thinned sanding sealer. That's either cellulose sanding sealer thinned with genuine cellulose thinners (not the reclaimed type from auto parts suppliers) or shellac sanding sealer thinned with methylated spirits. I've not used acrylic so can't comment. A 50/50 mix for the initial coat, so that it really sinks in followed by subsequent 75/25 coats. If you make too much of the 50/50 just add sealer to thicken it to make the 75/25 mix - that's what I use as standard. Then put it aside until you feel confident to tackle it.


For those that have an interest in spalting Dr Sara C. Robinson of Oregon State University is a renowned expert. Another one where she tries to educate the masses,
- https://www.youtube.com/watch?v=fWedsgkoxYY

A beginners guide from her Northern Spalting website
- http://www.northernspalting.com/beginners-guide/

Spalt Your Own - her Fine Woodworking article
- http://www.finewoodworking.com/how-to/a ... umber.aspx

 

[smartecosse]

Thanks for all the suggestions..........

Given it a couple of coats of sanding sealer and will see how I get on......