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I use the hot pipe method....haha hot pipe, and i'm having a lot of trouble, and have always had trouble bending my laminated bindings.

I have Hond. Rosewood strips .125 w x .1875 h with .010/.010 b/w fiber veneer laminations. i use urethane glue for my laminations and that seems to solve most of the de-lam issues when the glue is wet and heated (but not all, i sometimes have to reglue portions).

But i cannot get these things bent sufficiently without breaking. i've tried soaking them, misting them, dry, heating them with a heat gun then misting.... and i get to a certain point in the waist curve bend and they crack.

does anyone have a method that works, aside from taping them to the slats (because i already have the box closed). i would even try boiling them at this point!!!

thanks so much.

b

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brendan 3.0 new and improved, with better interpersonal subroutines

Sounds like too thick to me. Try .08-.100.

Dennis is right thinner is easier, I use a watlow heater on a outside form, an an old overholtzer alum bending form. I get breaks when the binding is over 2.5mm or 3/32

Agree that those appear too thick. Try thinning them. Also, tape the bindings together, putting purfling to purfling to maintain the correct shapes for right and left sides. This helps a good deal and helps even if you do have some delamination. Also, using a back strap like thin flashing or a bending strap like LMI sells helps fight breakage. Finally, use as little water as possible. Good luck.

Aaron

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Aaron Craig

Bending machine is the answer! One hour from turning it on until they've cooled down, and then I touch up any little spots on the hot pipe. My bindings never break, and it's so fast and easy! Building the machine isn't a whole lot of fun (unless you really like building jigs) and it'll take up your afternoon, but it's not expensive (I use light bulbs for heat) and it'll save you lots of time and frustration in the long run.

I decided to do one build without my machine for the sides and the bindings, and I can tell ya I won't do it again. I like my bindings to be a bit on the thick side when I bend them, and then trim them up flush with the sides, and you just can't do it with most woods if you're just using the pipe.

Good luck!

Let me preface this with a few disclaimers. I am a relative newbie. Currently working on guitars 3 and 4. I also do not own and have not used a bending jig. I also am not looking to crank out a high volume of guitars with the same body shape (although 3 of the 4 have been the same shape due to friends seeing my first and wanting one like it).

For me, there seems little need to spend the extra time and money needed to buy or build a bender. I bent sides for a 00 last night on a pipe. Highly figured claro at roughly .090 thickness. Took about an hour including heating the pipe, and there is rarely a need to retouch them. If you tape your bindings together and bend them as one unit, it takes roughly the same time to bend those, and with good technique you can bend pretty thick bindings without incident. From what I've read around here, .125 is dangerous territory regardless of the method you use to bend.

I'm not saying bending machines are bad. If I built commercially and routinely built using the same body shapes, I would no doubt own a bending machine, heat blankets, thermo couplers, controler, etc. I'm just saying that there is no need to rush to buy or make one if your needs don't demand it. Plenty of cracked sides come out of bending machines. Regardless of your method, it is all about becoming familiar with the correct techniques for said method. This last one took me an hour, and it was the first time I'd bent to a shape that small (the others have been J-45 shaped dreds - I think I can bend that shape blindfolded now ). But the first time I used the hot pipe, it took me basically a full day. I simply didn't know what I was doing. Now, I really enjoy it. I'm sure I would fight with a bender for a while too before finally working out the kinks. All this is simply to say: brenbrenCT, don't think or feel a bending machine is the only cure for your current problems.

Aaron

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Aaron Craig

excellent. thanks so much guys. i will take a combination of all the tips and thin my bindings, use less water, and give great thought to whether i want to invest the time in a bending machine.

considering i picked up 2 more commissions this week, and both for the same model, a machine might be a good solution for me.

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brendan 3.0 new and improved, with better interpersonal subroutines

Brent,

Bending bindings is touchier than bending sides. Being smaller, they're more prone to breakage, especially if you're using curly woods.

As mentioned already, thinner would help.

Effective bending machines can be simpler than those sold by Stew Mac and LMI. Mine really aren't bending machines at all, just bare forms which can be whipped out in a few hours for very little cost, inspired by William Cumpiano. They work fine for sides or binding.





A big benefit in using a form, IMO, is the support for the victim that slats provide, by preventing "kinking" which leads to breakage. I bend most bindings dry, with just a spritzing on the kraft paper that I wrap around the wood. I bend maple wetter. I've only used a blanket for a heat source on the forms, so I can't speak to bulbs that some folks use.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

i can't quite see from the picture, but do you use the round metal tubes to support the sides of the mold? i would imagine it is quite easy to make custom shapes with that. how does it work with cutaways?

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brendan 3.0 new and improved, with better interpersonal subroutines

Brent,

I glue in small wood blocks, about 1/2" sq x 4". If you'll be using bulbs, screw them in.

I've only done florentine cutaways so I just use these forms as they are.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

last question for you specifically Pat. Did you build the jig from plans or just sort of trial and error? If from plans, would you be so kind as to share the plans?

thanks
b

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brendan 3.0 new and improved, with better interpersonal subroutines

Brent,

I call it design-on-the-fly, simple enough to do without plans. They're usually just scrap from making the outside mold, birch 3/4" ply. Cheaper ply works too, but I hate the splinters.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

thanks Todd. that's quite helpful.

b

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brendan 3.0 new and improved, with better interpersonal subroutines

hey pat, where is the heating blanket in the machine pics. is it in the form under the fixed metal slat, or in the metal/wood/metal sandwich sticking straight up.

thanks

b

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brendan 3.0 new and improved, with better interpersonal subroutines

that heating blanket is one of the best investments I have made. It is very fast and easily adjusted. Nothing like it. I made my bending machine out of scraps I literally found in the street, being an avid recycler. Hacksawed conduit, tin snipped roof flashing, some bolts, particle board, a few pieces of 4 and 2 by 4, and a veneer press (only expense), made life a lot easier. I have a pipe and blow torch set up that I think takes too long, though it is useful for adjustments.

I try to remember the principle of KISS. You don't need a Rolls to deliver groceries.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

great advice everyone. bent my bindings last night and they came out great.

thinned them to .070 and they bent without any issues.

b

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brendan 3.0 new and improved, with better interpersonal subroutines