boiling wood ?!?!?!?

[SimonT]

I have heard a few times and watched some turning videos on youtube that mention boiling wood for various reasons, my question is why?

I had heard its a good way of destroying the blighted woodworm, but have also heard it helps the wood dry quicker? I wonder if anyone knows the theory behind this as I thought it would flood the wood with water making it dry slower?

Any thoughts? Or answers on the back of a postcard please. (Alternatively a reply on here will do :wink: )

 

[Bodrighy]

I am sure Chas or someone can come up with a good technical explanation but in simplistic terms wood has different levels of moisture in it from the outside to the centre so dries at different rates. This can vary from wood to wood hence some split, some warp and some seem to dry without either happening. The theory is that boiling it makes the moisture level of the wood the same so that as it dries it will maintain the same level throughout and lessen the chances of it splitting. Fine perhaps for pen blanks but unless you have a very large saucepan and an understanding partner it is not generally practical IMHO.

Pete

 

[SimonT]

Thanks pete,

Seems a bit obvious, I hadn't though about equalising the moisture content in the timber. Seems a bit obvious when I think about it now. Shall have to look out for chas' s version (unless he is kindly looking and can post a link to his version).

Thanks again

 

[bogmonster]

Whoopie,

I have an enormous pan 50+ litres and boiling ring and an 70 litre electric water boiler left over from my foray into all grain brewing. Most of the HB kit has gone now to make room for other stuff but I like the idea of boiling pieces of wood

Need to investigate some more. Will it stop all the holly I have got from splitting....

BM

 

[CHJ]

.....Need to investigate some more. Will it stop all the holly I have got from splitting....

In my experience Nope ! it'll just up your energy use bills.

My experiments were done in the earlier days when alcohol soaking, detergent soaking, boiling all seemed like good ideas to speed up the drying of rough turned items.

Alcohol soaking on some timbers speeded up drying time by a couple of weeks.
Soaking in detergent more often than not resulted in a stained slimy mess.
Boiling in a pressure cooker to save on energy resulted in some staining to dirty grey on pale woods and resulted in a couple of weeks saving, invariably the wood was harder and more unpleasant to turn than naturally dried wood.

Drying times were still dependant on final drying location and varied by species.
After the excitement of all the experimenting I settled for letting time & nature take its course and spend all the preparation time spinning bits of wood instead of pickling and cooking it.

Some conclusions I drew from comparing the various web references were that many were from different continents and totally different climates to the UK therefore had the possibility that significantly differing parameters over and above the 'method' were at work.

As to why boiling speeds things up, I presume it is because the cell walls are damaged and moisture transpiration is easier.

I'll try and find some of the old threads.

edit:- stick - boiling turnings - in the search brings up a few.

 

[bogmonster]

Thanks Chas. Maybe I should re-focus on the homebrew and pickling myself instead of the wood

BM

 

[Bodrighy]

Have to confess I don't even bother coating the ends with PVA or paint etc. If the wood splits I make smaller things with them Mind I do have a good supply from tree surgeons, gardeners and a furniture factory. Referring to Chas's comment about different climates. When I moved from Cornwall (notoriously damp) to Wiltshire (inland and a lot dryer atmosphere) I had quite a few turned pieces, some that had been supposedly stable split on me. Luckily I was able to do my usual trick of filling them with a contrasting material once they were stable again. Doesn't take much especially with woods like holly and yew.

Pete

 

[JimB]

I assume it's to help it dry without splitting. Our local butcher used to have two blocks that were just metre high solid logs about the same diameter. No cracks in them at all. He said in the old they used to leave logs in running water (for how long I don't know) to make butchers' blocks as they then dried without splitting. Of course, I only saw two of the successes.

 

[bobham]

I am not certain, but I believe the theory behind boiling rough turned bowls is to relieve stresses in the wood that can lead to cracks. The "glue" that holds the fibers of a piece of wood together is called lignin and boiling the bowl softens the lignin and allows the wood to "relax" into its new shape without cracking. I would think that steaming would work the same, the way it is done in steam bending wood. Possibly raising the temperature of the wood would also cause the bound water in the wood cells to boil and rupture the cell walls which would then allow moisture to escape easier and lead to faster drying, although it would seem to me that the wood would still move as it dried and could still crack. I have never tried any of the "accelerated" drying methods.

Take care
Bob

 

[SimonT]

Thanks everyone,

Think I may stick to rough turning my blanks in the future then, the theory at least makes sense to me now. But I agree with you bob, I would have assumed the wood is still under the same stresses and as such would crack or split when drying.

I have tried the microwave method with very little sucess (left it on full power (hammer) .)

 

[winemaker]

You may want to try this https://www.youtube.com/watch?v=MKnS1CTCYoQ

 

[SimonT]

Yeah I had seen that video winemaker, very impressive. It was one of the first videos I watched when I really started getting into youtube woodworking videos (which I find very useful).