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Old cars use a mix of metal chassis, wooden frame, and steel/alumin*m sheet nailed/screwed over the frame. Most of the timber is straight, but a few parts have substantial bends.

I am trying to repair the top rear edge of an Austin 7 roadster. This is bent into a horseshoe but with two extreme bends - probably 4.5" radius for nearly 90°. It is a plank/beam about 7ft long, 2" x 5/8" section. I suspect oak, ash, or some type of cedar.

Now, I can't easily get green timber, so was wondering what timber at my local merchants would be best for attempting this bend. I'm in Australia - Tasmanian Oak, Meranti, Pine, Oregan are easy to get.

Any advice?

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    An excellent topic for your first question! Please take a few minutes to take the tour and read through the help center just to familiarize yourself with the place. You'll note that the SE sites are a pretty well structured Q&A format, not just the regular ramblings you'll find at other forums. Welcome, enjoy, and all the best on your restoration! I'd expect some pics when you're done! – FreeMan Jul 12 at 11:51
  • My only note is to avoid woods that have been kiln dried. That sets the lignins, making bending harder. (This is slightly less applicable if you opt for lamination.) – Aloysius Defenestrate Jul 12 at 17:31
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You can bend most woods, some easier than others, but even the easier ones to work with can fail. Oak is one of the more common wood to use when bending so I would recommend that. I would strongly advise against using pine or any non-hardwood though. You definitely don't want to restore a car with softwood.

There are three main methods for bending wood:

  • Steam
  • Lamination
  • Kerf cutting

I recommend lamination. It's relatively easy, doesn't require any special equipment/setup, and laminated wood is very strong.

To perform lamination bending you want to:

  1. Rip your wood into thin strips (pretty much as thin as you are comfortable ripping on your tablesaw). Note: You want to cut these pieces longer than the finished product needs to be so you can cut them all flush at the end.
  2. Create a form on a flat surface in the shape you want your final product to be.
  3. Soak the wood strips in water and bend them into the form and clamp it together (use no glue at this point, this is just to create a "memory" of the general bend(s) you need). Leave overnight. You may snap some of your strips at this step so I recommend cutting a few extra to have ready for this. The more wet you get the wood the less likely they will snap but it is still possible depending on the grain orientation/knots/etc.
  4. Mark across the bottom and/or top of your wood strips to ensure you can put them back together in the same order/orientation.
  5. Take everything apart and let it thoroughly dry (note the wood will rebound some but should remain fairly bent when dry)
  6. Evenly coat all strips of wood with wood glue. (The site below recommends not using wood glue so you can choose one of their recommendations if you desire, but there is nothing better for gluing wood than wood glue so I'm not sure where they get off.) I would definitely use Titebond III for this since it is likely to get damp. (Titebond II would probably be fine as well but there is no harm in being over cautious.)
  7. reassemble, clamp, and let sit 24 hours.
  8. Cut the ends flush and plane the top/bottom flush
  9. Finish
  10. ????
  11. Profit

This wiki article on wood bending has some good information on bending wood but as I said above I do not agree with their recommendation against using wood glue.

I also would advise against using a bandsaw to make your rip cuts (unless your project is too tall to cut in a table saw; based on the dimensions you provided, it is not) as it will not produce as precise a cut as a table saw. If you must make your rip cuts on the bandsaw I would cut them a bit wider and then plane them flat.


Additionally I recommend taking a stab at a smaller project first using the same wood as there is bound to be lessons learned and you don't want to make a mistake on a large project using expensive hardwood.

  • TB III may not be the best choice for laminations in the long term. It tends to remain somewhat soft. Laminated parts (especially if they're under any stress) glued with TB III can creep over time, eventually failing. TB II and a good waterproof finish can help prevent this and result in a more stable end product. – dwizum Jul 12 at 19:26
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    Also - might want to add a bit to explain wood selection, you want to make sure you're getting strips parallel to the grain, or you'll break parts regardless of the species of wood. – dwizum Jul 12 at 19:29
  • Thanks for the detailed reply.Lamination would be easiest - could even buy laminating strips to save all the ripping - but the client doesn't want a ply/laminated result. – Nigel Pearson Jul 14 at 5:20
  • P.S. My father was a patternmaker, so my initial idea was a build-up of segmented blocks, but I'll try some practice bends before resorting to a hack like this – Nigel Pearson Jul 14 at 5:28
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    If you spend a little time trying to match up the grains, get the clamping right (as many clamps as you can get, as close together as you can get them), and plane/sand it really well it should come out looking more like a single piece of wood than a laminated piece of plywood. – Jesse_b Jul 14 at 14:47
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I suspect oak, ash, or some type of cedar.

I believe it will always have been ash.

European ash, Fraxinus excelsior, is one of the traditional coachbuilders' woods, valued for its strength and shock-absorbing properties as well as its ability to take bends well.

It's still used today for major structural elements in Morgans:

Morgan shop floor

From what I understand European hardwoods can be very expensive in Australia so it may not be feasible for you to use this even if you can locate a local supplier. American versions of ash could be equally suitable but no idea if they're available there or what they cost.

I'm in Australia - Tasmanian Oak, Meranti, Pine, Oregan are easy to get.

Tasmanian oak (actually some types of eucalyptus) and meranti (Philippine mahogany) are both viable options. Of the two I'd probably favour the tassie oak, in part because it's more likely to be from a managed supply. And this PDF from Forests NSW tells us that it bends very well, The Bending of Timber

Pine I'd discount on principle, regardless of species.... but especially if it's radiata.

Oregan (oregon?) may be douglas fir as one of the alternate names for doug fir is Oregon pine. If that's what it is even though it's a softwood it actually wouldn't be a terrible substitute, it's widely bent e.g. for boats and is stiff and (relatively) hard.

Air-dried v kiln-dried
Although kiln-dried wood is widely noted for being less suited to bending1 (up to and including the opinion "Don't do it.") it's widely used for the purpose as you might imagine because kiln-dried wood is now the norm, not the exception.

The following video on YouTube from Engels Coach Shop, Steam bending wood, 1" thick kiln dried ash. has much useful information. You may also want to have a look at this page on the Cornwall Austin Seven Club's site. A Google search just for "bending ash" will net much more information.

Now, I can't easily get green timber

You wouldn't want to use green wood for this because after bending you'd have to contend with lots of unexpected movement (including some likely warping). In addition, you'd have to wait for it to dry — a year or more! — before you could safely attach it to the existing components and during which time you could expect some cracks to form, even if steps were taken to seal the end grain well.


Expect some learning curve with bending, it's sure to be one of those things where it's more difficult in practice than it appears. There may be some subtle points that you only realise once you get hands-on with the process (there usually are) no matter how much you've read up on it and how many videos you've watched of it being done.


1 One of the basic issues with kiln-dried wood is that it's drier, but the EMC of either wood fundamentally depends on local conditions. In a humid climate wood will bend more readily than in a dry climate, regardless of how the wood was initially dried.

  • Thanks - great photo, and that Forest NSW PDF is an unexpected find. Interestingly, it rates Radiata Pine and Silky Oak as very good bendability. Not what I expected. – Nigel Pearson Jul 14 at 5:13
  • Yes I noticed that about the radiata, it's its low strength that I think automatically rules it out in this case. From what I've seen and read modern fast-grown radiata has wide growth rings and the lighter earlywood is soft and even spongy (much like the worst "whitewood" or "white pine" in Europe, which is generally spruce). – Graphus Jul 14 at 17:19

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