Unstable timber

[Hobbyhorse]

I have started my next wooden movement clock which is a Clayton Boyer design called Inclination : http://www.lisaboyer.com/Claytonsite/inclinationpage1.htm

The front and rear panels on which the clock is built are 1150mm long and 180mm at the base and of course stability of the timber is pretty important. I have built all of my previous clocks from European Oak but thought that I should use a NZ timber for this one. I have some swamp kauri (about 10,000 years old) and dragged this out for use. I cut the boards oversize and left them for 3 months to stabilise before straightening them and cutting them to shape. I made a pattern for the front and rear from MDF and set out all of the arbours , pivots etc and drilled them and it all looked good. This morning I went down to my workshop after a rainy night and found each piece had bowed around 4mm and was useless.

Back to the drawing board. I am not too sure whether the European Oak would be a whole lot better in that size and I now think I will go to American Maple which is a hardwood and has nice straight grain.

Yours in frustration,

Rhys:no:

[Buzza]

How long do you think you take on this project Hobbyhorse? Sorry I can't help you with any timber knowledge, but I do wish you well working at this wonderful clock.

[Hobbyhorse]

Hi Buzza.

I guess there will 60 or so hours in the clock. A project like this is a form of relaxation for me and I do not spend long hours to get it completed. I would hope to have it running in 6 weeks or so.

Rhys

[rrobor]

Have you thought of an Australian timber. Cupping etc is due to absorbtion of water so if you use a wood that doesnt do that I think it should be stable. My thoughts are Red Box. its very heavy and dense. It suffers from not being able to be glued because the glue wont penitrate but if you are making clock parts to screw together I think it would be great. Its also cheap so your bank balance wont suffer. Width would be an issue as most times its 100 or 120 wide but you may be able to get it cut if you dont want to laminate. The main issue is weight, its about as heavy as steel.

[GoGuppy]

I have started my next wooden movement clock which is a Clayton Boyer design called Inclination : http://www.lisaboyer.com/Claytonsite/inclinationpage1.htm

Wow, incredible clock designs!! The Inclination looks great, should be heaps of fun (or is that frustration :C?) to make and watch when it's done.
Let us know how you go and some piccies along the way would be much appreciated:2tsup:.
Cheers

[Cruzi]

Timber is dynamic and will move all the time.

You say you went to your shed one rainy night and the timber had bowed....

Were both sides of the timber exposed or just one side?, if you leave a piece of timber laying flat it will absorb more moisture on one side causing it to bow. This will happen with all timbers.

Allowing the timber to stand with equal airflow around it for a few days often will see the timber returning back to shape.

To stop this happening its best to seal your timber as soon as possible during construction.

Having said all that, timber is a natural material and it can and will do weird things.