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I'm just setting up to build my first guitar and had a question about bending. I have a steam box that I use for making Windsor chairs. 45 minutes in this thing and I can bend 5/8" white oak around a form.

If I put a mahogany side in here, I'm guessing it's going to turn to spaghetti pretty quickly. To start with, is that a bad thing? Secondly, if the wood's gotten very flexible, can I just fit it into a mold without using a bending iron?

Would serious heat and moisture compromise the structural integrity of the piece, or would it settle down nicely once given the opportunity to dry in the mold?

Thanks in advance for your help.

Steve

Personal opinion a steam box is a bad way to bend sides. yes the wood will be pliable quickly but will also dissipate that pliability quickly. Plus you will induce a good bit of moisture into the wood that is not going to be cooked out during the bending process under stiff support. This can and will likely lead to cupping cross grain in the sides as they dry. Hot pipe bending or fox style bending is a much better way to go for a plethora of reasons. Do a surch on steam box and you will find this has been discussed many times.

I used to use a steam box. The wood has a propensity to twist and warp and do all kinds of nutty stuff. I'd recommend at the least, a bending iron, at the best, a bending form with a silicone heating blanket.

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Brad Tucker

Steve welcome to the OLF!

I completely agree with Michael on all points. We have had this question before and invariably steam box users eventually use more conventional methods such as a bending pipe of a Fox or Doolin style bender.

Welcome aboard!

Steam some Lobster !
Then bend guitarwoods the old fasion way!!

Take your time and make a Fox bender or just a 2 1/2' pipe heated with a torch !


Welcome to the OLF!
Where we all learn from each other!!!

Mike

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Mike Collins

Thanks everyone. Did a search for "steam box" and found all kinds of interesting info. But don't worry, it won't be the last stupid question I ask around here

Thanks again

Steve

why not use the steam box and a fox bender? would you get the same cupping issues (and other odd warps) if you let the wood dry in the fox style bender, after it was in the steam box?

Here is the issue on the steam box. You incorporate too much water. Wood is made up of tiny cells. They will absorb the moisture and swell. This is something you cannot control. Yes you may get a set out bent as you want it once in a while . The trouble is the water will swell the cells and this will cause you all kinds of warping.
If you have a bender and try to incorporate the steam box and the bender , well again it may work some of the time but you will eventually have uncontrolled warpage. Heating NOT WATER bends the wood . In the heating you allow the cells to crush and this is what allows you to bend. Water in the bending machine is used as an anti scorch agent. It also helps from case hardening. Bending isn't difficult but you do need to have a feel for it. Also what how thick you make the sides. .090 is as thick as I would bend.
The few problems that you may have will be more technique oriented. Most people will over heat the wood , this case hardens it and in essence makes the wood very brittle . If you use too much water you will see warping . Not enought heat you usually see alot of spring back. In a bender you are using a machine and a process . If you spend more than 4-6 minutes bending the wood in a machine , you don't have enough heat or you are just working too slow.
I am done bending wood in about 4-5 minutes most of the time from the time I turn on the machine. I use heating blankets. I also use a thermometer.I want to know the temp of the blanket. I allow the heating blanket to heat my steel slat and that is what heats the wood. Wet wood usually holds at about 220 -230 degrees if it is really wet. As it dries the water cooks off and then the temp will spike. You want to heat the set to set the bend and cook off the water. Then let it in the bender until it is COOL.
Good luck. Benders are the better way to go and use a mold.
john hall
blues creek guitars

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
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