Burning bowl on kuksa - help

[yomperalex]

Hi all, i decided to have a crack at making a kuksa. I was given a lovely blank of beech and decided to make a large kuksa.

After having roughed out the exterior design I was shocked by just how bloody hard beech is (I swear I am never carving with beech again).

I decided to burn out the bowl using embers. it is slow work, but producing a nice bowl. only problem is that it is now developing a crack.

Is this a problem inherent with the technique? Is there anything I can do to stop it?

TIA

Alex

 

[stekker]

Boil it in salt water and let it slowly dry.
It prevents the wood cracking and sometimes the crack disappears.

Theo.

 

[Gill]

This might help ,it shows him boiling in salt water.

 

[Mesquite]

Did you burn the bowl out before or after you carved the outside, also was the wood season or green?

Reason being that if you burn it out after you have a lot less material so it dries out faster and that can cause cracks to develop, especially if the wood is green

 

[yomperalex]

Did you burn the bowl out before or after you carved the outside, also was the wood season or green?

Reason being that if you burn it out after you have a lot less material so it dries out faster and that can cause cracks to develop, especially if the wood is green

The wood was seasoned. There is still a lot of material to remove from the outside (is about 2 inches thick).

I will investigate the salt water boiling - any guidelines? Strength of solution, cooking time.

Thanks for the feedback.

Alex

 

[JJJ]

Its hard to advise with out a photo Alex. Seasoned Beech is unlikely to crack except if you apply heat. Boiling in salt is a technique used on green timber that is already shaped into a finished cup. My guess is it's more to do with stopping leaks and proofing as its not hard to dry a well made cup.Even if the crack closes when its boiled chances are that it will open again when it dries.
I know guys with cracks in Kuksas who don't have a problem with them as long as the use them regularly with hot coffee. But there are cracks and there are cracks! If the crack goes through 2" then I think you are doomed. If not I would suggest not burning the bowl anymore, but trying to carve it out. A crooked knife will still devour seasoned Beech if it is sharp and well made ( though muscle memory plays a big part), if not a gouge and mallet might be easier.
If there is still a small crack showing, try putting super glue in it, then sanding over it. You might need to do this a few times but it is a permanent solution.
Next time try green Beech. It's less likely to crack if you burn it out and is a joy to carve. But as Mesquite has said, burn and scrape before you remove the outer material.

Good luck
John