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Chris152

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I've made a couple of trips to timber yards selling air-dried wood and both times returned with one or two bits of wood that have a few exit holes.

Am I right thinking this is more likely to happen with air-dried wood than kiln dried? I can get both quite locally, but like the sound of working with air-dried more.

And is it best to just chuck the whole bit of wood if it has exit holes, or should I treat it and remove and bin the sections with holes?

I've searched around for advice online and know it's tricky knowing it the worm's active, if treatment has worked etc.

At the moment, the pieces with holes are sat in the garden waiting!

Thanks for any thoughts.
 
Hello
As far as I know the drying process in kiln kills em off.
What kind of timber and how much sapwood is there on the pieces you've got?
If those pieces were small enough to go in a deep freeze that would do the trick.
Maybe you could put something under the timber as it might make the frass more visible.
 
One of the pieces is about 8 ft - it's Ash with no sap wood- but I could cut it to short pieces and put them in the freezer rather than burn it. The others are a short piece of ash with no sap wood (it's been square cut) and a piece of sycamore with what looks like no sap wood between the bark and the regular wood. If that's possible?

How long do you think it needs in the freezer? It's all about 1 or 1.5 inches thick.

I'm completely new to buying wood like this, so forgive me if this all seems naive. Have I just been unlucky or does this happen often with air dried wood? I want to find a regular source and am thinking that kiln-dried is probably the way to go in light of these little critters...
 
Chris152":1jf9pqe6 said:
How long do you think it needs in the freezer? It's all about 1 or 1.5 inches thick.
Freeze treatments to destroy insect pests, including eggs, grubs and larvae work best when the temperature drops rapidly. The target temperature should be reached within twenty four hours throughout the object to be most effective, not just the surrounding air temperature or the outer portions of the piece. Insects can adapt to slow changes in temperature much better than they can cope with relatively quick changes. The freezer must be capable of taking temperatures down to at least -18ºC (-0.4ºF) and then once the object has reached this temperature it has to be maintained for at least two weeks. If the freezer can maintain temperatures as low as –30ºC (-22ºF) the treatment period, once the necessary temperature is reached, can be as short as three days.

A difficulty to overcome using freeze treatments is maintaining the moisture content of the object being treated. Water migrates out of wood as atmospheric RH drops, and cold air has very low RH so water moves out of wood and it may become too dry. Small objects must be wrapped and sealed in plastic bags to help maintain moisture content levels, and if air can be evacuated from the bag prior to freezing, this further helps maintain the object’s moisture content. If you were dealing with polished wood, which I don't think you are, then after treatment the wrapping needs to stay in place until the object properly reaches normal temperatures to prevent condensation onto it as this may cause damage to the finish. Slainte.
 
thetyreman":v27u84zc said:
if you don't like any of it, you can always send it me :lol:
If we wait a while it'll get lighter and cost less to post.

Sgian Dubh - That's really useful info, tho it does tend to put me off that method, lots of ways it could fail I guess.

Kiln dried's seeming increasingly the way to go in future, at least til I have a better understanding of wood and insects!

Thanks both.
 
I'm still wondering about this one. I read in various places that if the temperature at the centre of the wood is raised to above 55 Celsius it'll kill woodworm - has anyone built a kiln to do this? Apparently there are different methods, including using 'heat/ light bulbs'?

Thanks

Chris
 
Woodworm can't live in warm dry environments. I wouldn't even bother taking any precautions at all with this wood if the timber is destined for something inside a centrally heated house,
 
MikeG.":3mygvczx said:
Woodworm can't live in warm dry environments. I wouldn't even bother taking any precautions at all with this wood if the timber is destined for something inside a centrally heated house,
Thanks Mike - but am I wrong thinking that the larva themselves can survive and can exit the wood, but that they then die as adults? That'd mean holes will appear in the finished piece but they won't spread? Happy to be told if I'm wrong!
 
It doesn't much matter. If they can't survive and reproduce, I can't see that it makes much difference when they die. The fact is, 19C and normally dry timber is enough not to be troubled by woodworm, and beyond that there is a danger in over-thinking it, IMO.
 
I do tend to over think things sometimes (hammer) - but wouldn't it matter (say) if you sold a piece to someone and a year later lots of little holes appeared in it where insects had emerged? I'm only going on about this as I want to be clear about it.
 
Chris152":1acrox1p said:
I read in various places that if the temperature at the centre of the wood is raised to above 55 Celsius it'll kill woodworm. Chris
Heat of 50ºC (122ºF) and higher, maintained for extended periods, kills most insects at all stages of their life cycle, including the common furniture beetle you're asking about. Holding the moisture content of the treated object at an appropriate level is vital. In the early 1990s the German Thermo Lignum company was a pioneer in developing insect pest control using a purpose built chamber system with temperature and humidity controls to prevent damage to treated objects. This system controls atmospheric RH at a set point decided by the customer [usually 50%] and raises temperatures to 52ºC (126ºF) in the chamber and treatment cycles last, on average, twenty four hours. House longhorn beetle is more tolerant of heat and needs a temperature of 55˚C to kill the infestation at all the life stages, i.e., eggs, larvae, and adults.

As others have said, common furniture beetle cannot survive in dry wood, i.e., below about 12% MC, so any wood used in structures in a reasonably modern residential building subjected to decent climate control measures is highly unlikely to harbour common furniture beetle. The roof space, under eaves and the like might provide a suitable environment for the beetle, but that's a different scenario. Damp sheds are a good environment for the common furniture beetle.

I don't know of anyone that's built a kiln to kill bugs. I'm not saying it's not been done; I just have no personal knowledge of it and as a consequence can't offer any indication of effectiveness.

I have used air dried wood many times over the years for furniture destined for habitable buildings. I've never concerned myself about what might happen in a year or two if I've found evidence of common furniture beetle if I'm aware the piece will end up in a dry and warm environment for reasons mentioned above. If you're not building for that kind of environment, e.g., you're building for a cool and relatively damp one, then any existing beetle eggs or grubs in the wood can probably survive and hatch into adults. Not only that, there's the possibility of reinfection by new insects, as well as reinfection from those insects already in the wood. Slainte.
 
Right, I think the coin's finally dropped at this end. I've been struggling with how on earth I could achieve temperatures low/ high enough to kill anything living when moisture content in a standard centrally heated house will do the job. :oops: Thanks everyone for helping me get that straight!

I have a related question now I feel more confident about using air-dried timber:

A local yard has a variety of air-dried wood that's about 2 - 2 1/2 inches thick, maybe 8 - 10 inches wide and generally a few metres long. Assuming a moisture content of about 18 - 20%, what is the process of acclimatising and converting those boards into 1 inch thick boards suitable for use in furniture for a centrally heated house, maybe 10 - 12% mc?

Thanks.
 
I've not done it personally, but I reckon you have two approaches. The first would be to season the board at full thickness down to your desired moisture levels before resawing. The second, riskier, approach only works if it is 2-1/2", not 2", but is to resaw it by slicing in half to 1-1/4", then taking the other 1/4" off the outer face, hopefully leaving both sides of the board at approx the same moisture content. I reckon I'd still be putting the two inner faces to the outside, clamping the boards back to back, and crossing my fingers.
 
Chris152":1ud70oca said:
A local yard has a variety of air-dried wood that's about 2 - 2 1/2 inches thick, maybe 8 - 10 inches wide and generally a few metres long. Assuming a moisture content of about 18 - 20%, what is the process of acclimatising and converting those boards into 1 inch thick boards suitable for use in furniture for a centrally heated house, maybe 10 - 12% mc?

For 3/4"-1" furniture stock start with the flattest 1 1/4" sawn boards you can find. If it means driving a couple of hours to find them then so be it. Any other plan and you're just chucking ten pound notes into your thicknesser. If you were harbouring notions of re-sawing 2 1/2" sawn boards into furniture boards then I'd advise against.

Much of successful furniture making is down to getting the right timber in the first place.
 
custard":q2bm2hws said:
If you were harbouring notions of re-sawing 2 1/2" sawn boards into furniture boards then I'd advise against.
Yes, that's precisely where I was heading... :( That's a real shame - I know the person that owns the yard, it's walking distance from my house and he'd even offered space for me to work there. But I do have a fairly clear idea of what I want to be building at the moment and it involves thinner boards/ lightweight pieces - and I'm happy to do those trips out to get the wood I need. Thanks for the advice again - I seem to be on a pretty steep learning curve here!
 
You'd stand a better chance of resawing it on a bandsaw if those boards are quartersawn, but I'm guessing the
seller obviously won't sell you from the middle of the pile without selling the rest.
Worth going anyway, if your on those terms, I reckon :D
even a... just looking for again, thanks.

Was it ever an concern, back in those... cold house blues days :p with damp timber yards
A don't go there !!! kinda thing?

Tom
 
It'll certainly be pretty damp there today, if it's not been blown away.

Maybe it's time to move on to dining tables with thicker tops. How much more difficult than coffee tables can that be? #-o
 

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