oak dry rot question

[julianf]

This is dry rot, i think -

I, assume, the surface marking is an extension of the rot? It would seem to coincidental for it to be something else -

Should the whole part be discarded? The finished item would always be at lower than 20%.

 

[MARK.B.]

Could the edge damage be due to that area becoming wet and drying repeatedly over a period of time causing it to become friable (not the eating type) if stored outside perhaps the edge was not quite covered up .

 

[julianf]

Possibly.

Some of the wood where this was from was cut a couple of decades ago and has been sat ever since, but I have no idea as to the history of this bit.

The pattern looks nice but I just dont know if it's suitable for use or not?

 

[MARK.B.]

A quick rub with a plane should give you some idea

 

[julianf]

A quick rub with a plane should give you some idea

Forgive my lack of knowledge, but what am I looking for?

The brown flecks travel through the wood, as they are present in both sides and seem to follow the grain.

Let me see if I can't get a better photo...

 

[julianf]

 

[Sandyn]

Any signs of fungus? one of the pictures looks as if there might be some fungus, in which case there is a high probability it is dry rot. If the timber has been sitting for 10 years, it would have been consumed by now, Dry rot moves very quickly. It needs wet wood, but not too wet, then it spreads by the mycelium moving into the fresh wood. The fungus needs water, so it takes it as it moves. It extracts all the moisture from the wood as it goes.

The first pictures looks like wet rot which has dried out.

If the top part of the picture is a brownish mould which can be scraped off, then it's possibly a relatively new dry rot attack. The spores are in the air all the time.

 

[julianf]

I live in an old house (at least 1800s, possibly older)

Ive always considered fighting fungus as a game of environmental control, rather than eradicating every spore (which is impossible).

Ie change the conditions and the rot stops.

But, look up dry rot, and you would think that, at the first sign, you need to raise the house to its foundations, and quarantine anyone who has ever visited.

Which is what makes me fearful, even though i dont really subscribe to the logic.

I can mill off the surface easily enough, but, of course, that will atomise a lot of what is there.


The stuff on the edge is weak - you can crack bits off with your fingers, but a fingernail test on the "spalting" (for want of a better term) does not indicate any reduced strength.

Ill see if i cant make a pigs ear of it with hand tools to confirm if the marks really do go through the wood or are just on each side.

 

[Ttrees]

I'd take a hatchet to it, or bandsaw a bit off, before the plane, some of it looks good to me.

 

[Sandyn]

Ive always considered fighting fungus as a game of environmental control, rather than eradicating every spore (which is impossible).

Yes, it's not difficult to deal with dry rot if the attack has just started. It gets more difficult if the attack is advanced, but even then, it's just fixing the leak, replacing the wood, removing all affected material. It is recommended that you cut back 1m from affected wood. Mycelium can creep over areas with no wood and through walls since it carries it's own water supply. That is the real danger of dry rot, it can spread a long way from the initial attack, very quickly. You can get fluids to kill dry rot.
There is very low risk, even if rot is in the wood it won't have a fruiting body which produce the spores. What will the wood be used for?
It could be some other kind of fungus, but if I had a bit of wood which I knew had dry rot or suspected it had, I would just burn it.

 

[sometimewoodworker]

Yes, it's not difficult to deal with dry rot if the attack has just started. It gets more difficult if the attack is advanced, but even then, it's just fixing the leak, replacing the wood, removing all affected material. It is recommended that you cut back 1m from affected wood. Mycelium can creep over areas with no wood and through walls since it carries it's own water supply. That is the real danger of dry rot, it can spread a long way from the initial attack, very quickly. You can get fluids to kill dry rot.
There is very low risk, even if rot is in the wood it won't have a fruiting body which produce the spores. What will the wood be used for?
It could be some other kind of fungus, but if I had a bit of wood which I knew had dry rot or suspected it had, I would just burn it.

We had dry rot in our family home it came around 80 years + after construction and about 50 years ago, it was under and in some of the floors on the ground floor and required parts of flooring , support beams and knee walls to be replaced. It was reasonably easy to cut off the rot effected ends plus an allowance to ensure it was eliminated. We certainly did not get rid of all floor planks and beams that had had part of them attacked by rot.

Nobody suggested that an 8 foot plank that had a 6” section with rot needed throwing out when cutting of less than 2’ was all that was needed.

 

[julianf]

What will the wood be used for?
It could be some other kind of fungus

End cheeks for electronics. Think 1970s style audio stuff.

So the item will never be in a damp environment again etc.

Really I have no idea what it is. Im only diagnosing using Google images, which, if you ask any GP, always leads to a diagnosis for the worst form of cancer (etc)!

The weak bit at the side has obviously got to go, but I just don't know what the flecks are. I made an attempt with a hand plane and the colouration seems to run through the wood.

It should be noted that Dr Google did not show me any photos of similar flecking from dry rot.

 

[Sandyn]

Nobody suggested that an 8 foot plank that had a 6” section with rot needed throwing out when cutting of less than 2’ was all that was needed.

I think the 1m is being ultra cautious and will depend on the size of the wood affected. Wikipedia actually shows the 'traditional' method was to cut back 1.5m, but their section looks as if it came out of a commercial removal company standard and they give a 20 year guarantees, so ultra cautious....and the customer is paying for it!

 

[Sandyn]

End cheeks for electronics. Think 1970s style audio stuff.

So the item will never be in a damp environment again etc.

If that's the case, it should be no problem

 

[Woody2Shoes]

I think you're overthinking this. The black flecks are almost certainly the mark of some kind of fungal activity - not unlike the other board you showed us all the other day. If the timber (minus the manky sapwood edge) is dry and finished with varnish or something similar and kept indoors it will outlast all of us. Crack on with your project!

 

[Woody2Shoes]

https://en.m.wikipedia.org/wiki/Spalting

 

[julianf]

Thank you

The reason I "overthink" it is that these bits are going on other people's kit, and I just need to make sure before I risk shipping somthing with errors that I do not understand.

 

[Chris70]

https://en.wikipedia.org/wiki/Mycelium

 

[julianf]

I took the belt sander to it today -

The brown bit at the side is soft, but the more interesting pattern seems just as hard as the surrounding wood.

I think it will look nice if it's safe to use (which you have told me it is, more or less!)

Thank you.

 

[Cabinetman]

The brown bit as you call it yes definitely get rid of that, I’ve seen it more orangey though in the past. The other bit looks like the start of oak turning into brown oak which again is caused by a fungus, harmless this time. Ian