How to bend wood?

[ElgaKoster]

I need to bend some back splats for chairs with the grain, the bottom of the splat needs to fit onto a curved seat rail. Any tips for bending wood easily in miniature would be appeciated. Many years ago somebody told me to soak the wood in a water and vinegar solution and then fix it to a glass bottle with the curve you need and put in an oven on low temperature , that is if I remember right of course.

[WeekendMiniaturist]

I would try this without the vinegar, as I'm not sure  if vinegar has an effect on the finish.

I would also cut my slats with the grain of the wood vertical direction to help it curve.

I am more inclined to let the wood dry naturally, and between two pieces of wood that I have shaped using the band saw and sanded for the shape desired for the slats then the oven method.  

Miniatures require lots of patience, eh?  and time waiting....  

Referencing The Scale Cabinetmaker Vol 12 no 2, Bending Hardwood for Miniatures by Donald Peck, (the project is a bentwood chair).

"The best method is pre-soaking wood in water, followed by steaming or boiling in water.  After the wood is pre-soaked by immersion in a bottle of water overnight, it should be heated with boiling water or steam for one half-hour to improve bendability.  However, there is a little advantage gained in steaming rather than the simpler procedure of immersion in boiling water.  Since miniature stock is small, it can simply be put in a pan of boiling water for one-half hour.  Bending should be done quickly while the wood is still hot; bends fail more frequently when the wood has cooled."

Referencing The Scale Cabinetmaker Vol 12 no 2, Drawing Room Grand Piano by Barry Appleyard  here is he preparing to bend wood for the the piano case

"Noting which way the grain has to run... soak them in hot (not boiling) water for 10-15 minutes.  Remove them from the water when they are flexible enough to curve into the mold.  Insert them into the outside mold butting each piece end to end.  Then carefully insert the clamping block or inner mold and clamp until dry (about 3 to 4 days).  This is the one time when it would be handy to be an octopus, but if carefully done with constant checking and rechecking before clamping it is quite easily accomplished.  Don't try to hurry the drying time.  If the wood dries too fast, the wood tends to check."

One magazine and two different methods and both discussed using boiling water and NOT using boiling water.  

Think about a plaster mold application for making a dolls body.  I would create a similar wood mold for the desired chair slat, or at least have something strong to cup around the bent piece of wood.

Glass bottle + piece of wood to be bent+ bigger piece of heavy plastic to bend around bottle and wood.  Then I would use really strong rubber bands to hold everything together - and let dry, and set and forget it ... resist the urge to check on it.  I suggest the heavier piece of plastic rolled around the wood piece because your edges are sometimes difficult to manage.

I did bend wood for the piano case in this project.  

Hope this helps -

Tamra

 

 

 

 

 

[ElgaKoster]

Hi Tamra thank you for your input, between what you said here and some other people on Facebook I went with boiling the wood for about 15 minutes last night and clamping it overnight. Since I don't have time to wait four days and won't have it in Castine either I took it out this afternoon, it bent beautifully and was nice and dry. I clamped it onto a dowel with a smaller diameter to compensate for spring back of the wood. On this particular piece I didn't want it to curve all the way to the top, so I only clamped it towards the bottom. On this photo it is just set in loose, I need to do a bit more handwork on the crest rail before I can glue it all together.

[MeezerMama]

Elga, your chair is looking beautiful! 

I just wanted to warn you that there is such a thing as cooking/steaming your wood too long.  I have found that if I steam or boil my wood for more than about 10-15 minutes it destroys the lignins in the wood and then it won't bend well and won't stay bent. 

Of course the timing does depend on the thickness of the wood. 

 

 

 

 

[ElgaKoster]

Thank you for the warning Chris, I will keep it in mind for future projects and experiment wth new woods, in this case it worked perfectly, the wood bent beautifully and looks great after it has been sanded, stained and finished. I am busy making a second chair from a beautiful unknown South African wood, wonder how that is going to bend, it is a lot harder than the cherry. I going to a wood supplier in Cape Town next week that specializes in our indigenous woods and I am hoping they will be able to identify it for me. 

[miraclechicken]

This is a very interesting topic. Elga the chair is coming out great! (I have been clicking on "unread content" and still I never saw this picture of the chair.....)

[Kathe]

Hello .... great advice on bending wood! I'm new at this and my question may have a common sense answer so please forgive me..... you cut your  wood before you bend it correct? Thanks!

[ElgaKoster]

Yes Kathe, you need to cut your wood into the final shape before bending, if it is a piece with tenons that need to fit into mortises on other pieces you need to also do that before bending. The wood cools down quickly so you need to have everything ready to put it into your bending jig as quickly as possible.

[Kathe]

Thank you. !!Hello .... great advice on bending wood! I'm new at this and my question may have a common sense answer do forgive me..... you cut your  wood before you bend it correct? Thanks!