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The 5 Ways I Do Wood Bending

Here are the 5 ways I have done wood bending in the past and a quick rundown of what’s involved, their strengths and weaknesses and how to do them.

1. Soak it

Soaking timber in a container ready for bending
Soaking wood in a tub. I usually fill another smaller tub with some water and put it on top to keep the wood submerged

This technique is as simple as soaking your wood in water and laminate pieces together after

The great news here is that this is pretty straightforward for anyone (including students) to do reliably.

An image of wood bending in the jig for making a ukulele
Soaked wood in the jig

It particularly works great for thin timber.

The longer you can soak the timber the better. Overnight is best although using warm water can help speed up the soaking process.

Basic Steps

  1. Soak timber in water for a period of time
  2. Put it in a jig
  3. Pull it out and wait for it to dry
  4. Glue two, three or more pieces together and put it back in the jig

Strengths & Weaknesses

Soaking wood to bend it is pretty bulletproof, and when it is laminated it will hold its position well.

However, if you do want to do a lot of these you will need a lot of jigs, and the three steps of soaking, drying and gluing (which take around 24 hours each) take time.

2. ‘Kerf’ cut it.

We used to do this when I worked in the cabinetmaking factory. We’d have big sheets (2400x1200mm) and we’d run them up and down the rip saw. It was time-consuming but got the job done.

When we started making ukuleles I used to brace the inside of the body with kerfed pine. I used to make students make all those cuts.

kerf cut wood bending
Timber cut along the inside face to help it bend around a tight-ish corner

There are better ways to bend smaller bits of timber, but if you have a specific large sheet you want to bend this is a good option.

Basic Steps

  1. Cut timber to size
  2. Mark the slits for every 3mm – 5mm depending on the sharpness of bend required
  3. Cut trenches leaving only a couple of millimetres solid
  4. Fix to something else to hold shape

Strengths & Weaknesses

Great for big panels and although tedious, this technique is faster than soaking in water. It can also be done to any piece of timber or board that you want.

On the negative, to hold it’s shape, the kerf cut wood needs something else to support it (even another kerfed piece would do), and it is tedious, especially when compared with bendy ply.

3. Buy Bendy Ply

What I used to make students kerf cut, I now use bendy ply for. It does the same job, looks nicer and saves an hour of class time.

This is definitely the quickest way to get a bend.

Basic Steps

  1. Cut to size
  2. Make sure the correct side is on the inside (in my case it’s the white side)
  3. Fix to something else to hold shape

Strengths & Weaknesses

This is certainly the fastest way to get a bend in wood as the bendy ply comes designed for wood bending.

However, it doesn’t look great (at least the ones I have seen) and it can be a pain to handle a sheet of it because it wants to bend all the time.

4. Steam Box

This is the most elaborate way to bend wood. But it is also the only real option for most species of timber cut thicker than 2mm.

You need a box, and a way to get steam. The steam is the easy bit, get yourself a Wagner Steamer.

These things are used for wallpaper but they are easily converted to a plywood box (or even PVC pipe).

My box is made from plywood. It’s OK and will get the job done. If I had to do it again I would probably use a large PVC pipe (around 250mm diametre I reckon, with caps on the end)

Putting some dowel in helps the steam penetrate all sides of the timber you are bending.

My steamer gives around an hour of steam which (according to various google searches, not my own research) will bend about an inch thick of timber.

Remember that wood is stronger when it is bent so you don’t need the thicknesses that you might be used to.

Basic Steps

  1. Soak timber in water (I find this helps although may not be necessary in every case)
  2. Put it into the steam box
  3. Pull it out and put it into the jig

Strengths & Weaknesses

For anything over 2mm thick, I think this is the best option. This technique has been perfected by people like Thonet and Charles and Ray Eames (famous designers).

This technique can be time-consuming, and take some test runs before you get the piece that you want (my experience).

5. Heat it

This is probably the least common bending technique that I have seen but it definitely has it’s place

Using a heat source (I use a butane torch similar to this one) and a steel rod you can bend thin pre-soaked timber to some really tight turns.

This isn’t one I do with students, but I did make a set of toilet paper roll holders with this technique.

Those bends are 90 degrees with about a 10mm radius.

This took some testing and research but got there in the end.

Basic Steps

  1. Soak timber in thin strips
  2. Heat metal rod
  3. Bend your wood over the metal rod

It can help to have something supporting like leather on the outside of the bend to help prevent break out

Here’s a short video of me bending the toilet roll holders

Strengths & Weaknesses

Using a heat source and a steel rod will get you the sharpest rounds in my experience. It is great for small stuff, in particular, for arty stuff like twirls.

It doesn’t work on timber thicker than 2mm (my experience) and you really have to watch break out.

General Tips for Wood Bending

  • The type of timber matters, try a few different types when you are starting. (I’ve found Geronggang and Blackwood work well, Tassie Oak doesn’t.)
  • Use timber with a straight, parallel grain (if the grain is angled the piece is more likely to break in my experience)
  • The thinner, typically the easier to bend (this is where laminating later comes in handy)
  • Laminating bent pieces helps give pieces strength and hold their shape better.

FAQ – Wood Bending

Where should I start when I want to bend wood?

It really depends on the job. I find the best way is just to soak timber, then put it in a jig and laminate it later.

How long do you have to soak wood to bend it?

If all you are doing is soaking it, then you need to penetrate all the way through the wood. This will change depending on thickness, however, 24 hours is usually pretty good.

Can you bend wood without water?

You could leave it face up in the sun, this would create tension in the wood and make it bow. However, this method is unpredictable and hard to replicate similar pieces so it’s not usually advised.

How do you permanently bend wood?

You can use any of these 5 techniques above to reshape it permanently. Soak it, Kerf cut it, use Bendy Ply, Use a steam box or use a heat source and some steel rod.