Bending wood -- options

Products and methods for bending wood. March 23, 2002

What are my options for bending wood for furniture? I have tried cutting kerfs in oak, and the boards splintered when I bent them to shape. I do not have the time to make a wood steamer, and regular plywood won't bend the amount that I need it to. I have heard of a special type of plywood that bends that would then take a veneer. Or there is a way of "layering" a bent piece on with laminated pieces?

Forum Responses
There are many ways, such as laminating 1/4" or 1/2" stock in a form. Pliable MDF is also an option, should you choose to veneer. These are just a couple and it really depends on the component you are building.

Wood selection is an important part of bending. Select a piece with consistent, straight grain. Spacing and depth of kerf are also key issues. If that is all too much trouble, try kerfing the plywood. Properly kerfed, we bend 3/4" ply down to a 3" radius, and solid 3/4 down to around 6".

Ask your lumber supplier about bending luan or bender board or noodle board. Pretty cool stuff. I have used it on 3 or 4 jobs so far and it has worked well. Once you veneer it, it will hold its shape with minimal spring back.

You didn't say how big your radius was. I successfully laminated 1/8" red oak strips into a 1" thick radiused front edge on a reception office desk. Smallest radius was 12". Once you've got the strips ripped, the glue up is quick and pretty easy, just lots of clamps and little shims. I used gorilla glue and the glue lines in the finished product are indistinguishable. I did wish I'd had one of those new edge lipping planers. Had to cut it down to the laminate with a block plane!

Look at Eames furniture. They made molds and bent wood into all kinds of cool shapes. It takes time to build a nice mold, but once you have it, it is easy to crank out a bunch of pieces. I recently made a bent ply stool that has a 6 inch radius and it was like butter to build after I made a nice mold.

Doesn't take much time to make a steamer. Most boaties make them out of old water heaters with the tops cut off. We made one for bending up to five inch widths using twelve feet of cast iron sewer pipe threaded at both ends and capped, one cap drilled with a 1/4 inch hole. Put in a gallon of water, set it in a fireplace at about a twenty degree angle, and steamed the bends. Iron stained the oak, though trim was painted. For furniture, look up threaded aluminum electrical pipe.

Use Italian bending ply or hoop pine.

The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor U:
I have been bending solid timber for 23 years for architectural and furniture components. We developed a process that has the ability to bend up to 220 pieces per hour, from dry, pre-machined, ready-to-use wood in a lot of cases. Like all processes, we have limitations. Steam bending is stretching fibres, compaction and compression, elevated using the end and back pressure around a jig with clamps to hold to shape. Our process softens the structure, particularly the lignin, allowing us to bend and slide the fibres. Impregnation then drying happens within cycle times of 6 minutes. The new memory is locked, by shutting the pit holes and not allowing reabsortion of moisture into the fibre. Drying required is extremely precise and fast. All species require different recipes. There are so many, but in general the softwoods are more difficult. You in the USA and Europe are blessed with excellent bending timbers. We are a stand alone wood bending operation. Solid is our preference, however, to achieve thicker dimensions due to the economics of impregnation times, we bend and laminate in one process.

For those wishing to set up a simple steam system, you do not want superheated steam. Wet steam is most effective. This will work: a generator of steam (jug or whatever) steaming into the centre bottom of a level pipe (say diameter 150mm (6") or whatever is required) with a piece of sack draped over each end. Put a couple of stainless horizontal wires through the pipe to ensure timber doesn't sit in the water created on the bottom. Success will come with practice.