Advice please! - steam bending single piece recurve

[rlogan]

Hi guys, could anyone offer me any advice?

I'm trying to steam and bend a single piece of wood into a one piece recurve bow and having difficulties. I'm not using any particulalrly nice peices of wood, just a decent board I have. I'm lucky in that I'm using a stam bath used @ work for cleaning stainless steel pipes but after a couple of hours steaming it just doesnt appear to be very plasticy at all.

I havent roughed the shape out yet, perhaps that may be part of the problem as i'm trying to bend too much material?
Or perhaps my form is the problem and the curves are far too deepset. I've seen vids on youtube and they don't help really.

Any advice would be brilliant.

Thanks.

 

[carl7]

Probably the best place to ask would be a woodworking / furniture makers forum. I know FineWoodworking the magazine if it still exists, used to have great articles on wood bending, both solid and laminates. I don't imagine Youtube would be of much help.

Carl

 

[WillS]

Every wood type needs a different amount of time steaming before it can be manipulated. Yew for instance is very quick, while I've found ash takes forever and has lots of springback.

What are you using?

The best method I've found is to try and steam or heat in situ. Get the bow clamped to the form up to the area that needs bending. Set up the steam (I use a heat gun, does exactly the same thing!) and hang a weight off the end of the bow limb. As the heat penetrates, eventually the wood will soften to the point where the weight can lower the limb tip.

There is no guessing or timing with this method. Once the wood is ready, you can see it drooping down into the form and then you clamp it up and leave it for a day or two to normalise.

It's tricky with steam because of the apparatus required to do it near a form, but Del had a great post on his blog using a wallpaper steamer and some sort of container. You could do it with a big polystyrene box as well. I tried it once and it did a fairly good job. As I said before I use a heat gun. I either wrap a wet towel round the limb followed by tin foil and heat that, or smother in veg oil before heating, just to minimise scorching. Steam is no less.risky than dry heat, as steam heating actually forces moisture out of the wood, whereas many believe it's safer because it's "wet" heat.

Either way, don't try and force the wood, let it move when ready, and don't time it. You might end up pulling it out of the steam 2 mins before it wants to move.

 

[rlogan]

Thanks for the help Wills, I'm not actually sure what the wood is, my best guess is pine.

I've experimented a bit and broken the bugger but at least I now have at least a feeling for what im looking for. It flexed quite a bit but didnt really set, even after 24 hours being clamped.

I think I shall experiment some more before purchasing anything decent.

 

[Deleted member 7654]

To be brutally honest, if you don't know what the wood is you should be trying to make a simpler bow.
Recurves look very pretty but are a pig to tiller. If you want a recurve it's better to laminate in the curves.
Having said that, steaming in curves isn't too difficult.
the main thing is getting from steam to former in zero time, which is why I often steam in situ.
Google Bowyers Diary and search for steam bending... yes the search engine on the blog actually works!
As willS said, too thick can be a problem too.
best thing is to get some confidence in the process. If you don't believe it works ... it won't work!
Get a slat of 1" x 1/4" or some such a few feet long clamp it up at one end with a brick tied to the other end.
Fix up a 5L plastic container over the slat near the clamped end and feed in steam from a wallpaper steamer.
After about 15minutes the brick will start going down .
Get some Hazel, we are rapidly aproaching the season for copicing and local volunteer groups etc will be working in woodlands etc. There is probably a group near you, check council website or BTCV (British Trust of Conservation Volunteers)
Hazel is straight, knot free, easy to work and steams a treat.
This bow was a twisted bit of Hazel, I steamed out the twist and added static recurves just to see what it would shoot like (fast )
Bowyer's Diary: Recurve Beltane Hazel Full Draw
Del

 

[rlogan]

Thanks Del, I liked making the laminates but just thought I would give this a try.

I will definitely look out for hazel, in fact I might know someone who will be coppicing soon now I think of it.

I think I will go down the wallpaper steamer route as the steam bath doesnt seem to be up to much. I'm only experimenting at the minute as I say but confidence is definitely half the battle.