Bowl split! but..

[badgeringtim]

Well i posted some time ago about how much wood to remove from the center of a halved log to prevent it splitting.
Lots of usefull suggestions so heres what i did;

Got a >40cm ash log, split it and removed a good inch from the center,
Got blisters adzing out the center,
Put into plastic back with shavings to keep it green and carried on working it intermitently for 3 weeks.

Was nearly finished this weekedn and had it our in the nice sun and BAM a huge split appeared. Looking disheatedly at the bowl this morning the split is now not gaping and barely noticable.
I thought he bowl over the 3 weeks would be nearly dry and not susceptable to lots of movement, but i presume in the sunny day (compared to the damp bag in my car boot) it lost a lot of moisture. The crack was easily 4mm wide, and now appears hairline. The walls are around 5-10mm which i thought would be ok to not split etc

So should i have not had it out to work in the spring sun, was i just unlucky or is there something here to beaware of?

Nedless to say i was hacked off as i dont often get big wood and had spent a long time working on it.

Roll on the Autumn bowl course!! :-(

 

[Harmony]

Boil the green bowl in salt water.

The salt is absorbed into the wood cells and makes it hygroscopic. The bowl will draw moisture.

Harmony

 

[mr dazzler]

wood doesnt need salt in it to "draw moisture" it already does that, its a natural law that woodworkers have had to deal with since year dot.
I reckon the sudden change of humidity level (our air has dried noticaebly the last few days) and a rapid warming in the sun are likkely responsible. Luck plays its part, but with experience, luck plays an increasingly minor role in proceedings. I made a kuksa about 3 or 4 weeks since, and its the first one I made which hasnt split. Dont be discouraged

 

[badgeringtim]

Oh but i am discouraged!

It must have been well over 20 hours invested in that blooming bowl!

But it was interesting how the crack gaped and is now barely visable now the atmosphere here has gone damp again. I know that makes sence but its still kinda mad to see it in front of your eyes. If i had known i would have taken a gaping and closed shot to post.
Im not entirely sure how the salt boil would help my predicament unless it stops the splitting?

I was really happy that leaving it in the damp bag worked very well but am now thinking that when in the latter stages i should probably take it out the night before really not convinced that it would make any difference though.

I do like the signature btw mr D

 

[mr dazzler]

Wood is a fantasically versatile and useful material to work with, but it often has a mind and will of its own.....Failures happen, (admittedly 95% of the time down to my lack of skill and/or experience rather than vagaries of wood movemets....) Think of it as a learning experience. Rome wasnt built in a day. Developing axe and adze technique, strength, stamina, how you would improve to do it different next time etc. Maybe you could do a tasteful rpair job?
Last night I axed out a piece of ash to make a forging-hammer handle. Within 20 minutes of being next to the stove a 2mm crack had emerged. This morning it has virtually closed back up again.....
stick with it Tim :You_Rock_
cheers Jonathan

 

[Harmony]

I rough out whatever I am making green, boil it in brine, slow dry, then finish it.

No cracking.

Harmony

 

[leaf man]

i just used seasoned wood, at least 2 years after its felled. it is alot harder but i find i have less trouble with the wood, but more you have to sharpen your tools alot!
keep trying though.
wood is wood. without your hand and crafting, it will be nothing more

 

[mr dazzler]

here are 2 alder dishes I started maybe 14 months ago, from 10 inch logs, about 16 inches long. The walls are still well over a 1/2 inch thick. No cracks at all, at any stage so far.

I started these about 3 weeks ago, in willow. None have split. They are pretty much dried out already. Just roughed them out and left them in the boiler room. Almost all these willow batch were carved heart down (which means the bowl will tend to cup into a deeper tighter curve as it dries and shrinks)

I have other bowls in progress (no pics) from sycamore and beech. None have split out of maybe 3 dozen made so far. Kuksas were more tricky, but I was trying to get them from too small a blank.....They begun to work when I used a 1/4 of a big fat log instead of 1/2 a thinner one.......
Point I am making is that what counts is being choosy about your stock material, reject wild grain, or stuff which comes out of a crooked billet (it has inbuilt tensions which will want to release themselves) Also not trying to get too big an item from too small a blank, remove plenty of the wood next to the pith, and dont worry. Boiling in salt may work but its not really necessary at all.

 

[HillBill]

wood doesnt need salt in it to "draw moisture"

I think he meant it doesn't draw moisture. Salt is the cheap way to stabilise/dry wood. Then theres de natured alcohol amongst other things which dry wood quickly and replace the water in the tubes with something that doesnt cause the wood to move.

 

[HillBill]

Oh but i am discouraged!

But it was interesting how the crack gaped and is now barely visable now the atmosphere here has gone damp again. I know that makes sence but its still kinda mad to see it in front of your eyes. If i had known i would have taken a gaping and closed shot to post.
Im not entirely sure how the salt boil would help my predicament unless it stops the splitting?

I was really happy that leaving it in the damp bag worked very well but am now thinking that when in the latter stages i should probably take it out the night before really not convinced that it would make any difference though.

I do like the signature btw mr D

Don't be discouraged mate, it happens to everyone at some point. If you knew how many knives and sheaths i had to scrap when i started making because of a fault i had done along the way you wouldn't feel so bad.

Just seal the split either with superglue or PVA and sawdust and crack on, it adds to the charachter of the piece but wont affect its use.

Chin up mate Its a lesson learnt and the education is worth much more than the piece of wood, Plenty more wood in the trees

 

[phill_ue]

Nedless to say i was hacked off as i dont often get big wood and had spent a long time working on it.

Oh, help! My ribs are about to fracture! I think I may have inadvertently wee'd myself!

 

[badgeringtim]

Oh, help! My ribs are about to fracture! I think I may have inadvertently wee'd myself!

oh... blush....

 

[leaf man]

Tu tut tut...
Cant stop giggling though

are you having any better luck with your carving yet, or have the tools been sent to 'the drawer'?

 

[mr dazzler]

I think he meant it doesn't draw moisture. Salt is the cheap way to stabilise/dry wood. Then theres de natured alcohol amongst other things which dry wood quickly and replace the water in the tubes with something that doesnt cause the wood to move.

I can understand salt helping to dry wood, not so sure its any more reliable to prevent cracking than would be careful selection of material. Whatever works for you.....
I forgot to mention, this
http://www.youtube.com/watch?v=iMT-YPNiXQs
Kuksa was kept frozen while not working on it. Huge lumps of ice crusted up around it in the freezer, and I broke these off before restarting work. Maybe that dryed the wood out faster than normal? I just wanted to avoid mould, willow (and sycamore) is prone to that....

 

[robin wood]

I suspect by keeping it in the bag you have not let it dry out at all and then working it outside on a sunny day perhaps with a breeze it is subject to very rapid drying causing a lot of stress. Best way is rough out quickly down to 10mm then start to let it dry slowly. Still air and cool environment eg unheated garage are best for the first few days then you can relax more. Having said all that as Mr Dazzler said clean straight grained wood free of tension counts for a lot too.

Here are pics of my last bowl course.

http://greenwood-carving.blogspot.com/2010/02/wooden-bowl-carving-course.html
Learning how to work quickly and efficiently is good to. Everyone on this course carved 2 bowls in 3 days. If you have less time invested in each one then you can afford to be more experimental.