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Will i am ready to bend the guitar sides. So i decided to make a bending machine so the sides come out perfect every time. I bent some practice wood by hand but did not come out good. so i just made this machine let me know how i did. I have to get this project done by March so give me all the tips you can!

Line the insides of the bending form with aluminum foil to keep it from charring.

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Jim Watts
http://jameswattsguitars.com

ok i will

You'll need a pretty stiff steel slat to follow the form, the steel rods are too far apart and too far from the edge to provide support.
Check out page 2 of this thread, it's got photos of a form for an L-00. I also use light bulbs, but that method does not heat the waist enough until the waist bend is completed, so I heat the waist area with a clothes iron.

viewtopic.php?f=10133&t=37283&start=25

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Gerardo,
At the very least you'll need the steel slat as Roger said. Got to say that at first I tried the light bulb bender, but didn't work that well for me. Just couldn't get things to heat evenly enough. So for my first two builds, I bent on a metal pipe with charcoal heating element. After that I went back to the bender after getting a heating blanket. After the first two builds, I realized I was hooked on building and then the silicon blanket seemed like a good investment. Wish you luck and hope you'll let us know how it turns out. Roger seems to have found a method that works.

Rodger, nice build. I had copied a plan for a bender in a book "A Guitar Makers Manual"
I got 0.1 mm thicker stainless steel sheets than he recommended because they all that was available.
I crammed in some big lights, small high power are not easy to come by here.
I did not realise I had to wait 45 min for the temp to get stable, then after bending leaveit on for 15 min.
So I got a heat blanket but it is very difficult to control the temp.
I use the light jig now, but need to bend Curly White Maple from Stewmac for a Benedetto copy.
Any tips, tricks, I have heard it is difficult to bend.

What's the wattage on your bulbs? I use two 150 watt bulbs on the ends with a 100 watt bulb in the middle. If I left mine on for 45 minutes it would catch on fire. It's hot enough to start bending in 15 minutes, and if I can't get the side bent and clamped in 15 minutes, I have to turn it off. Usually only takes 5 minutes or so to bend a side, unless it's bloodwood. Some of that stuff is really difficult to bend.

I have enough steel bars in mine (1 1/2" center to center) so that it stays hot for 10 or 15 minutes after I unplug it. I usually bend, shut it down and let it cool for an hour, plug it back in for 15 minutes to recook the side, and let it cool.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Forget about light bulbs and pick-up a heating blanket and a couple (I use three) slats from John Hall at Bluescreek an OLF sponsor.

Sure bulbs can work but you will be waiting and waiting and the lack of uniformity of the resulting heat very well may destroy more side wood material depending on your preferences than the costs of upgrading to a blanket and slat system. I believe John also has heat controllers for the blankets, mine came from him 10 years ago and has performed flawlessly ever since.

Also I've read a lot of posts on the OLF.... and other forums through the years and can remember at least two fires that resulted from bulb equipped benders being left on.... likely because it took so very long.... So there is this too, certainly super important for the safety of you and your's my friend.

Lastly if what happens to you is much like what happened to me your tastes in very cool wood may get more expensive in time.... I can hear 100 voices saying "Roger that".... And if your Luthierie path takes you in the direction of building for others, deadlines, commitments, etc. bending blankets produce more reliable results for beginners in my experience, pros too.... which makes them a contributor to keeping your prospective clients happy campers as well.

And really lastly and forgive my poor humor please - good thing you didn't load that thing with those fat-rase, Al Gore CFL light bulbs....

I'm only on my second guitar build, but have built violins for around 10 years. Having used heated pipes, bending irons, bulbs, and now finally heat blankets (LMI bending system) I wouldn't think of using anything else now. Easy, fast, consistent, and safe. With voilin bouts and waists, i just went by feel, and that worked well after a learning curve was ascended and I developed a feel for the wood. With larger guitar sides, I really like being able to see live-time temps climbing, and bending at the optimal temp. Still need to "feel" the wood, but IMO its much easier to learn. Good luck, whatever system you decide to use.

We bend a bunch of sets every day -- our production benders in fact use bulbs to provide the heat. Several caveats -- we pre-bend the waist curve on a separate fixture like Taylor and other factories, The form is totally closed to trap the heat, the form and the bender itself are metal lined. Our method uses the inner most waist apex as the locator for the entire bend and build process (again like Taylor). We do use blankets on the cutaway benders. Most importantly "all our benders have heat controls and 30 minute SHUT OFF Timers

No offense intended but the bender in the OP is flawed in many ways and will be problematic and as pointed out is a fire hazard. A Google search should yield an original FOX plan I know its posted on the AGC Forum.


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Ken Cierp

http://www.kennethmichaelguitars.com/

Listen to Hesh, he knows what he's talking about. I'm an amateur builder, and only build one or two a year. I'm not interested in increasing my production, so I don't need a blanket.

Just because bulbs work well for me doesn't mean I'd recommend it for everyone.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon