Wood in burnout

[Ronhal]

I have made a piece in wood which I would like to cast in bronze. My question is can it be successfully cast using the investment process and burning the wood out or should I be looking at making a mold and wax model?
Any help appreciated

[wolff]

You are almost certainly better off making a mold than trying to burn out the wood. Unless you are speaking about a very lightweight and exceptionally thin wooden form (think paper-thin balsa), I doubt you`d be able to evacuate the pattern without damaging the investment mold. Even if you could, the odds are good that you have a solid piece of wood, or at least one that has thicker walls than the bronze that you would like.

If it is a relatively simple form, you could consider using the wood as a pattern for a sand mold. Otherwise, seal it, take a mold and cast yourself a wax.

Bill
www.billwolff.net

[racine]

wolff is right. sometimes u can get away with it, with a very soft wood, given a hot dip of wax and a strong ceramic shell with blow out points for the ash and gasses. the trouble with wood is that as it burns it twists and expands with great energy and ca n easily destroy the mould.
moulding wood with silicone is wonderful, you can even find well grained sections, cast them and join them in the wax.....without the carpentry, you can do stuff comparatively effortlessly that would be otherwise extremely technical or evn impossible... twist, bend, melt etc.

the great thing about bronze is that when you understand its potential the possibilities seem limitless. i can think of no greater tool for the contemporary artist. unfortunately the opposite trend is the resposibility of many british artschools* theres a tendency to look on the 'weight of bronze' ie some odd notion about victoriana.. and dismiss it with little true knowledge. mind you i find there is a trend towards the technically inept as a clique. very narrow minded.

*there are bright spots however, eg cardiff where they are expanding and modernising the foundry facility.

[malakiblunt]

Well i have cast directly from wood very sucsfully casting direct from small tree branches useing ceramic shell investment, the first time i tried it i messed about bowing air down in side the molds in an effort to help the wood burn, but now i dont bother i have had castings were ther is a core of charcole inside, but its caused no problems what so ever, and the detail of the bark is absolutly superb, i even cast a twig cover in very heavey lichen wich came out perfectly though clenind the investment of that one was a night mare!.
But to recap casting from small tree branches about the thickness of a mans thumb has always worked perfectly for me.

i have atched a not very good pic showing some of branches in one of my pieces, Ikarus his wings were direct cast useing branches and 'feathers' made from wax, oh the irony

On a slightly more macabre techique i have also done direct casts from road kill the claw of an owl for exmple, this did cause problems with the claws expanding and bursting the mold but i sloved that with stainless wire rinforcment, its also a bit smelly at burn out!