Thread: Tightest radius in steam bending

200mm is perfectly fine for steam bending, but it depends what you want to bend. 12mm sq would go around a 100mm radius.

13-16mm sq or round would be fine, but you would probably need a form to pull it around as it will still be a bit tough.

Anything over that (30 x 30 mm ) bend in thinner sections (say 30 x 6mm) bend all together and laminate up afterwards.

great, thanks. I assume you mean 12x12mm not 12mm^2? That's actually about the thickness I was thinking. What do you think of stringy and the moisture content?

Good Morning Harry

I have steamed quite a lot of Tasmanian bluegum - (E Globulus - a different species from Sydney bluegum) - and Messmate Stringybark - (E Obliqua) and find that both usually bend quite well. Sometimes wood snaps for little visible reason and sometimes it bends unevenly or twists due to internal stresses in the timber, I think.

Rule of thumb is to steam for one hour per inch of thickness. Wood should be very pliable when it comes out of the steamer, but it cools/dries very quickly - so you must work very, very quickly. Perhaps one minute of work time. If it sets when partially bent, then it will not fit back in the steamer!

I always use a bending template, welding gloves (its real hot!) and I rehearse before the wood goes in the steamer. You do not have time to think later.

Also, overbend a little as wood has a memory and springs back a tad.

Hope this helps. If you are an experienced bender, please disregard!




Fair Winds

Graeme

Dry timber is hard to steam, about 20% moisture content is ideal. Back sawn is better than quarter sawn. Stringy will steam but there are better timbers ie Jarrah, Spotted gum, Mountain ash. Work quickly, as you only have a minute or so. Dont just do one, steam a few lengths and pick the best.