First try at bending

[John J]

More pics.

[ken cierp]

Looks nice -- I just want to say that I spent years going down the path of internally heated benders. I would highly recommend a few things. Make a reflector to cover your bulb sockets, use silicone wire inside the bender, cover your profile forms with aluminum, and lastly always bend the waist curve on a pipe first (and eliminated the that hold up bar thing at the caul). Snap one rim side of a $100 set and you'll wish you did. The single purpose design in the link worked OK for "D" not so much for real tight waisted styles. $.02

viewtopic.php?f=8&t=4

[John J]

Thanks Ken.
I covered the inside of my forms with foil tape. I did pre bend the waist with my pipe bender. By doing it that way you can eliminate the bar underneath that pinches the waist? I'm using a custom caul matching the waist curve I made from mdf. When you say a reflector for the bulb sockets do you mean something like a sheet of aluminum with holes cut out for the bulbs? I'm using 3 200 watt clear bulbs.i appreciate the help.

For the novice any rule of thumb on temps and time?

[ken cierp]

Yes you have to have the inside of the form covered with foil to prevent a fire. My point was that our production forms as pictured in the link are covered with .023" aluminum along the profile eliminating the sandwich process.

Yes pre-bending the waist curve eliminates the need for the support and spring. Biggest mistake made in side bending is leaving the material too thick, I picked up on the Martin factory, sides are .075" -.078" +/-

I take the cut off material left over from the side after its profiled and use it to determine a good temperature for the waist curve bend. The form itself can be much cooler.

This procedure works well because the heat is being applied to the inside of the curves -- the compression side.

[John J]

More questions. Should you profile the sides before thinning or after. Or doesn't it make any difference. Also should you glue backs and tops up before or after thinning?

[ken cierp]

I always thin the sides before profiling. Backs and tops thinned to about .15" before joining the halves.

[Jim Bean]

Not trying to hi jack a 4 year old thread. I am new as well and I would like to mention my current success. I bought a steamer kit. Thought well maybe for the start up this may be the key. I'm sure it will get me there but I do not think that was a good idea. I am trying to build a cut out dreadnought. The cut it is just to tight. I do have a heat gun and tried to use that. Today I'm going to the hardware store to build a bending iron with pipe and the heat gun. Hopefully later I can build the $200 bending jig. Point is steamer would work on standard dreadnought not cut out. Also steamer doesn't give the tight nice bend the shape does not hold and it losses the heat before you can finish. Steamer sucks.