Nasty pyrography surprise....

[tekno.mage]

I was just pyrographing the wood name and my makers mark on the base of a box I'd just finished (I think the wood is Iroko, it was a piece from some old hardwood joinery offcuts someone gave me) and as I finished the first O in Iroko, I heard a strange little cracking noise - then watched a tiny hairline crack open across the base of the box. It goes all the way through as well.

Grrrrr. :evil:

That's never happened before. It's not even as if the base was particularly thin (I've made thinner ones from other woods and never had this problem.) Must have been some invisible defect/hidden stress in the wood.

Bother - now I have to get the superglue out and persuade it not to ruin the finished already applied to the inside of the box.

 

[stev]

Its never fun is it when that happens?

I guess the immediate lesson is to try and do as much work as possible before assembly so if things do go wrong you will have a much easier time repairing or replacing components.

What finish have you put on the box base? Do you need to superglue the inside? If the crack goes right through it could be repaired from the outside with the superglue to provide support to the crack and then filled with wax or shellac on the inside which would be easier to clean up.

Whatever method I find masking the surrounding area is always useful to avoid the surrounding grain getting clogged with wax or glue.

Good luck.

Steve

 

[tekno.mage]

Luckily the inside was finished with Osmo Oil - which meant when I trickled superglue into the crack on the outside, any that oozed through could be easily wiped off the oiled inside. I've been able to recover the situation fairly well - but the crack is still just visible - the pyrography and decorative rings on the bottom of the base have camoflagued it somewhat. It's more obvious on the otherwise beautifully smooth inside of the base - well it is to me - my partner say's it's hardly visible and no one but me will ever notice it - but I will always know it's there

The pyrographed signature and wood name is one of the last things I do to a piece (aside from oiling & final buffing) as it goes where the chucking spigot used to be. I guess applying a very hot wire to end grain wood is quite a stress and potentially can reveal a hidden defect. What was weird was the way that the crack happened just after I'd pyrographed the "O" and had lifted the tip from the wood - not while I was actually doing it.

 

[stev]

Doh! I should have noted that you'd posted in the turning forum (I just picked up the thread from 'view new posts').