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For a while I had issue with wood bindings being really difficult to bend, and when installing they refuse to conform to the body (leaving ugly gaps that aren't apparent until the glue dries).

I find thinning the binding to something like .080" or less makes the binding much easier to bend, and it conforms more easily than thicker binding bent to shape... I used to really crank up the heat to bend maple binding but that ended up burning and scorching things.

Any other tips and tricks for wood bindings?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

You can go a bit thinner than 0.80 if you want to make things easier.
Overbend the waist a touch, underbend the bouts a touch.
Make the bindings of 2 laminated pieces, you probably won't need to pre bend them.
Avoid Ebony and other very hard brittle woods.
If the bindings don't fit, use a bigger hammer.

Round off the inner and outer corner of the binding before you glue them on. Rounding off the inner corner allows the binding to "sit down" better in the channel (which will always have a tiny radius in the inner corner) and rounding the outer corner means you can pull the tape harder before it breaks.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Height of the binding is critical too, especially on the back with a radius of 15 or 18 ft. Don't cut the bindings more than .250" high, I like around .230". Remember, you are also bending the binding to match the radius of the back,, which will cause it to pull away in the waist and upper bout.

Chuck

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You're not alone. I hate binding. I think my problems are mostly due to a compounding of errors, though. Bending sides by hand results in curves that aren't 100% smooth, cutting binding channels by hand results in more imperfections on top of that, and then I have to bend the bindings to match every tiny kink perfectly. And most bindings I've used had at least some amount of runout, which makes them twist if you bend them square over the pipe, so I have to figure out what angle to hold them to counter the twist, while matching imperfect curves, and compensating for the back radius pull-away effect... takes forever. And even when I finally think it's perfect, there's still a gap somewhere after the glue dries Sometimes I can re-hydrate and heat the glue and squeeze them out.

I need to find some suitable rope to try that clamping method and see if I can get away with less perfect bending.

Trevor is spot on. Since knocking off the inside corner my binding is so much better, in fact it's probably my favourite part now. I found using a steel slat and bending all 4 strips at once on a hot pipe works really well.

I read the bending all 4 at once thing on Cumpiano's book... it also allows you to bend purflings sideways, which aren't possible by itself (so you can have matching purfling under your binding). This of course saves you a lot from having to buy pre made binding that comes with purflings.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I don't think it's bending sides by hand that is the problem - unless you are getting some very odd kinks and that only tends to happen in highly figured woods.
As I see it there are a few issues:

A less than perfect binding channel. Any binding will have trouble fitting to a poorly done rebate. Form your rebate by using the lining overhang method and it becomes easier.
Binding that has a twist. Makes it much more difficult to clamp and it might be impossible to force it into shape. Ebony that twists is awful for this - just no 'give' in the wood.
Clamping that is insufficient. Try another method.
Don't try to fit the bindings too closely to the channel. As I stated previously, overbend the waist, underbend the bouts. This method effectively pulls or clamps the binding to the channel as you tape/rope around the Guitar. It's what the factories do. It's also what the Violin makers do when bending their ribs/sides.

I glue in a short section at at time, maybe 2-4 inches, but tape the next 6 inches in place. What I do is gently press the binding into the channel, working my way around, looking close. There will be a spot where pressing the next inch in will cause a slight outward bow in what I just pressed in, that is where I make a mark, and stop. I will glue up to that point, but use tape only to hold the binding in place past the bunch-out point. Then when that glue sets up, put more glue in with a pallet knife, and repeat. Takes forever, but does a good job of compensating for those little imperfections.

To be more accurate, I use the binding rubber bands from Stew Mac over the tape, they apply more force that tape alone. And if a spot is particularly stubborn, I used a bar clamp pressing on the rubber bands.

I know this is not ideal, but after all the trials on my first two (had to bind both twice, learning to bend ebony, etc.) it did work. End result was on two guitars, I only have one small segment on the back of the ebony one that shows a gap. Not bad for a beginner. Hope to speed this up some day with practice!

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Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

I did not know about the rounding inside/outside corner trick... will do that next time.

What other wood can we use for "black" binding? Ebony is about the only black wood I know of... unless I use a really dark variety of EIR... I haven't tried to bend ebony but I hear it rather break than bend.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Maybe I've just had good luck with black ebony. I haven't had any trouble being .25" x .08" at all.

I wrap it in craft paper (Tai, that's just thin brown paper here in the states), quickly run some water over it until it's damp, run the bender full on, start bending around 230F, stop around 320F, use the dimmer/router speed controller to bring the temp back down to 300-ish, and let it sit for 10-20 minutes.

When bending purfling attached to binding what glue should one use to fuse them together that will withstand the heat?

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Doug

Don't let fear or common sense stop you from trying to build something

Round inside corners, thick ca , clamps and tape

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MK5acoustics.com

Q'd Macassar Ebony has always bent like butter for me. African ebony bends more like cheese. You might get string cheese, but you might get feta.

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Pat

Thin bindings to .075"
Bend bindings and purfling together but not glued together.
Glue purfling with CA to bottom of channel and match with end graph purfling
Round off inside corner of binding
Glue binding with LMI white glue using tape and 1/8" shock cord

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guitarsbygiltzow.com

You should use Elmer's polyurethane. I think it might also be called Probond, or something like that. I get mine at Home Depot, but surely other places have it, too. If you find the bottle with a bull on it, that's the one.

Gorilla PU glue foams more (not a good thing at all), sets up faster, and is harder to spread because it is a thicker viscosity. I'm not aware of anything Gorilla PU can do that Elmer's can't do better.

Hope that helps.

I just stick a bit of Hide glue on. Doesn't fear the heat.