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I have been using a home made side bending machine and heating blanket to do my side bending....I have bent mahogany,bubinga, and rosewood which is my favorite so far...I start my bending around 250 Deg and will usually complete the bend when the temps hits 300 degrees. No broken sides ......yet....I now have an order in for curly maple and bloodwood .... Now, I am sure that there are other woods that need higher temps to bend.....Is there a chart around that gives you the temperature ranges for bending different woods.....Also , what things to look for in different woods....difficulty in bending,,,tone...etc......Maybe there are threads here but I can't seem to find any......Larry

Larry John Hall at Blues Creek would be a good one to go to for specific bending temps. Perhaps he will weigh-in here.

I found this chart in an Elderly brochure and I think it was originated by Martin - it seems pretty accurate in terms of describing tonal characteristics to me.

These are from an article that John Mayes wrote.

Indian Rosewood: 300f
Mahogany: 310f
Maple (bigleaf): 290f
maple (European): 280f
Brazilian Rosewood: 305f
Cocobolo: 310f
Koa: 300f
Paduk: 310f
Walnut: 300f
Other Rosewoods: 300f

A thread a few days ago mentioned 350-400 for Paduk and Zebrawood. It kind of threw me for a loop as I never read anything stating that high of temps.

Hesh and Zack....Thanks for the response....Heres where I get a little confused.....When the temp reaches 212 the water in the wood starts to turn to steam......At 240 -250 you are within a safe range to start your bend......Once that bend is completed , which if you bend at a steady pace, the process should be completed at about 300 degrees or less.....The only task then is to cook of the remaining water keeping the temp at around the 300 degree mark......In the case of Zebra wood ...at what temp do you start your bend?.......If the answer is at 250, then why bring it to 400 degrees.....Just trying to get this straight .....Don't want to break any of these beautiful woods......Larry

Thats my question as well. The first side I ever bent was as piece of scrap HOG. I had the termometer in the wrong spot and it said I went up to 340, but was probably a lot higher. This thing was toasted. Havent had a problem since and never go above 315-320.

Bending isn't rocket science but there is a learning curve. Another thing is that one piece may not bend the same. I have found that to get repeatable bends you need to get the wood to collapse cells in a controlled manner. This is done with heat. Water is mostly an anti scorch agent.
Most woods will bend between 275 - 325 degrees F. Scorching will occur with a heat and time. I have found that there are 3 woods that will need more heat . Mahogany - Maple - Paduck. Maple and Mahogany I use 375 . I start bending at 350 and you can see how I do that at my site. Then I will let the heat go to 390 then let it cool to 200-225 and hold it for 15 minutes.. Do not take it out of the bender till it is cool.
Paduck well this is another wood that needs a lot of heat. I don't even think about starting the bend until I see 375 and then hold it at 400 for 2 minutes to set the bend. Again holding at 225 to 250 for 15 minutes.
Moisture can cause more trouble for warping and I use only a very small amount. Soaking is not a good way to apply water. I use a spray bottle and apply just enough water to dampen. The only time I deviate is when there is a high figure. At that point I use wet paper, once I am bent I blow the water out and be careful not to get a steam burn.
If I use paper I will hold at 275 and let it steam till dry.
hope this helped

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
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You Don't know what you don't know until you know it

Are you guys talking about bending on a pipe or in a Fox style bender ???
How the heck are you measuring these temperatures??

I bend on an electrically heated pipe and I really have no idea what the temperature is....
If it seem to cool, I turn it up.
If it seems to hot, I turn it down.

You guys have me wondering how I've managed to get by so far !!!

Mark

Those guys are probably all using Fox style bending machines...which is really a better way to go. You'll get much better bends, much easier.

On a pipe, I get the thing hot enough to steam the wood, but not hot enough to cause a lot of scorching. That seems to work for the woods I've bent on the pipe.

If you are planning on building more than a couple guitars..it would probably be worth it to get a bender put togethor.

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http://www.PeakeGuitars.com

When bending a wood that's new to you, you should be able to feel a distinct point when the wood relaxes, even using a fox style bender. When hot enough, a lower bout with the weight of the heating blanket on top will practically bend iteself.

Wenge also needs more heat than most. It will bend at OK but it won't hold it's shape unless it gets quite hot.

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http://www.chassonguitars.com

For the most part I am in total agreement this John H. here. Time and temp both play a role in scorching. you can scorch IRW at 200 degrees if you leave it there too long. Most woods will bend between 275-310 pretty well. most wood I will start the waist bend at 275 and as I will mention later bend it about 3/4 ways full. There are exceptions both sides of this temperature rule but for the most part these temps work well for me. Don't use too much moisture, don't take too much time to make the bend. I like to bend the waist 3/4 full then do the lower bout fairly quickly and the upper bout then finish the waist. This should take about 3-6 min max from sstart of the waist bend to completion of the waist bend. This pulls material from the lower and upper bout and makes the bend tight to the form everywhere. This is of course on a fox type bender using heating blanket and slats. I use Kraft paper and or aluminum foil as my wrap.