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Sven
12-15-2013, 12:55 AM
I've ruined a lot of binding strips while attempting to bend them on the pipe. Last night I stumbled onto a solution that helped me avoid that. I was going to bend two strips so I wet them and put them on some brown artist's tape, the kind that goes sticky when you soak it in water. The purpose was just to keep them together, but they bent much more easily at the bout at which I started. So I put some tape on the inside of the waist as well, and managed to bend these fairly thick padauk strips without them cracking.

I think the tape worked in two ways but can't rule out a third. First, the tape kept the moisture in the wood longer. Second, the tape acted as a backing strip on the outside and strengthened the strips, much as a spring steel piece would. Third, I noticed some gunk oozing out of the wood. I can't say if this was oil from the wood or if the cellulose glue from the tape crept in. Anyway it worked and the tape was dead easy to scrape off before glueing.

Some pics in this link, but not necessarily more info:

http://www.argapa.blogspot.se/2013/12/facing-my-fears-of-binding.html

So if you crack binding, get the paper tape out.

Gary Gill
12-15-2013, 01:27 AM
I am currently binding a couple of my pear shape tenors. The bodies are cherry with spruce tops. The bindings are maple. I used the side bender to form the bindings. The first set cracked at the small radius. Second and third sets formed fine. Binding is more challenging than I expected.

jcalkin
12-15-2013, 03:00 AM
Nice pix, Sven. Your bindings look really thick. That makes for a cool look, but even with a bender they can be a hassle. I usually take them down to .065", and they never give me problems in the bender. For the look of wider bindings I'd probably make up some purflings out of the same wood---not quite the same look, but pretty close, especially if the wood has no prominent grain structure. Also looks like you are really good on the hot pipe. I'm envious.

Michael N.
12-15-2013, 03:18 AM
Try my method (which I stole from the machine benders): wrap them in foil. You should only need it at the waist area and watch your fingers because the foil gets mighty hot! It helps retain both the heat and the moisture. In fact it can work a little too well because you will need to retain the bend for 30 seconds or so after you have taken it off the pipe. I sometimes use the method for difficult sides.

Sven
12-15-2013, 04:34 AM
Indeed, the strips were thick. Thicker than the width of my rebate. But I gave it a shot, blame the success on the tape. And I took off about a third with a contour plane after glueing! I know of the trick of having the rebate slightly deep and then scrape the sides, but I found it easier to press them into place this other way around. I've bent binding for sopranos in my bender, but as that is the only size I have a bender for I need to do for others on the pipe.

Moore Bettah Ukuleles
12-15-2013, 07:00 AM
Wipe your bindings with thin CA glue before bending and you won't have any problems. I make all my bindings .080" because I like a nice radius on all edges. No sharp corners or edges for me!
For years I've used 3" blue tape on all the outward bends of difficult to bend woods (extreme curly koa). Make sure you get the tape on while it's still warm though or you'll never get it off. For tight radius areas like you have on cutaways, a little thin CA glue helps there too.

Ooops, just realized this discussion is about pipe bending. I've only used the techniques described about with heat blankets. Maybe it'll be helpful to someone else.

Timbuck
12-15-2013, 08:16 AM
Don't you mean get the tape off while it's still warm Chuck :confused:

Liam Ryan
12-15-2013, 08:43 AM
I use a bit of that metal strapping they put around pallets as a backer when pipe bending bindings. It doesn't remember the bends unless you kink it.

Beau Hannam Ukuleles
12-15-2013, 09:14 AM
I read Kent Everett (a maker of very good guitars) uses .060" black fiber for his bindings and glues them on with CA glue.

I asked him about it and he said he gets them here:

http://www.gurianinstruments.com/products-page/marquetry-and-inlay/fiber-strips/

I bought some but haven't used it yet for binding.

I think this .060" black with a full depth white at .020" for purfling (with a normal .080" binding ledge) would be a good, quick, cheap way of binding/purfling that would look good.

PS- i just noticed Gurian do .080" black fiber too

bigphil
12-15-2013, 12:01 PM
Wipe your bindings with thin CA glue before bending and you won't have any problems. I make all my bindings .080" because I like a nice radius on all edges. No sharp corners or edges for me!
For years I've used 3" blue tape on all the outward bends of difficult to bend woods (extreme curly koa). Make sure you get the tape on while it's still warm though or you'll never get it off. For tight radius areas like you have on cutaways, a little thin CA glue helps there too.

This is interesting and I'm going to try it. What is going on though? I mean, how does it work, I would think the CA would seal the wood and keep water from penetrating? You do still wet them when you bend them with this method don't you?

Kent Chasson
12-15-2013, 12:55 PM
An application of "Super-soft" veneer softener can help on some woods. http://www.veneersupplies.com/products/Super-Soft-2-Veneer-Softener-Conditioner.html

The fiber is also available through Grizzly. I think their material is more layered and papery than other suppliers. This can be a good thing in that sanding gives you a subtle marbled look. More organic than perfect black. For search purposes, I think most manufacturers call it "fish paper" or "vulcanized fiber".

Sven
12-15-2013, 08:48 PM
Lots of good ideas here, thanks all! Indeed I think fibre might be the way to go, I intend to try it as a purfling feature without the need for a separate purfling rebate and just glue it to the inside of a wooden binding strip. But I'll keep on using brown paper tape on the outside of the bends, it worked perfectly and there are no fumes or solvents to be scared of.

Sven

Beau Hannam Ukuleles
12-16-2013, 03:47 AM
These Taylor guitar videos were a revelation to me in regard to wood bending and water content.

https://www.youtube.com/watch?v=jxEqGqi4D-E

Still, i use water

Moore Bettah Ukuleles
12-16-2013, 05:54 AM
This is interesting and I'm going to try it. What is going on though? I mean, how does it work, I would think the CA would seal the wood and keep water from penetrating? You do still wet them when you bend them with this method don't you?

I'm not sure why it works but I've used these techniques for many years with good success. Maybe the ca makes the wood stronger or keeps it drier. I came up with the tape idea thinking it would act as a tension skin on the outer bends but maybe it just keeps the water away. (One benefit is that it keeps the side absolutely clean. But I bend using almost no water anyway. My sides go in a canvas envelope that's been slightly dampened but I don't wet the wood down directly. (And yes Ken, I meant to say to remove the tape while it's still warm.) I also use two heat blankets and three spring steel slats for what that's worth.

I've never had much luck with the Gurian fiber binding. For one thing, it's not jet black (don't try to combine it with ebony on the same instrument.) It's more of a black pepper color but it's only obvious in the right light (direct sunlight for instance.) I found it very hard to power sand and the edges would knurl up. It feels like you're working with hardened leather. It's not for me. As far as protection though, it's going to be a lot tougher than any wood you could use a binding. I just found it hard to work with. And it's fake.

resoman
12-16-2013, 06:38 AM
Ever since I read about Chuck's bending method I've been using the same for bending sides and the bindings too. Works great. Lately I've been bending the binding as a continuous piece with no join at the tailblock. It looks great and no join to mess with but it takes me a long time to bend by hand so I'll go back to bending on the jig.

afreiki
12-16-2013, 08:40 AM
Regarding feeling like hardened leather - and this may be a really stupid question - has anyone ever used leather for a binding? Would it dampen tone do you think?
Anne Flynn