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Hi everyone,

First time try at installing wood binding. I bent purple heart binding using my heat blanket and form. I glued the first side, then the fit the second side and glued that.

Unfortunately I didn't do a very good job of dry fitting the second piece. Its a little too long and so there is a section in the upper bout where there is an approximately 1 mm gap between the binding and the top.

The glue used is fish glue. The question is, could I unstick part of the binding? I would then shorten it with a sanding block and re-glue it. How best to unbond? Heat? or perhaps warm water?

I could also rout of the binding and try again, seems a shame to undo all the work if I could just make a small adjustment, though

Stefan

picture's way too big, can't see anything.

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Peter Havriluk

Heat and water is very good at releasing fish glue.
BTW, pic's awful big!

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Put bits of wet paper towel on it for an hour or so to rehydrate the glue. Then heat and it should come right off.

Thanks for the replies! I'll give moisture + heat a shot tomorrow.

Sorry about the pic size. I couldn't figure out how to re-size it. I'll do more digital pic research next time

As far as fitting that last segment, I use a scrap block of 12/4 cherry about 4" wide and a foot long set on it's edge right next to the body where those final pieces come together. When I'm just about to that joint, I can let the last few inches of the binding rest on that cherry block and trim it a little at a time with a sharp chisel before applying glue to the last 5 inches or so. Of course, that chisel needs to be "razor sharp" not "new-from-the-store sharp" or you'll end up crushing the fibers and possibly splintering the PH. It's one of the reasons I try to avoid PH in general... too splintery for me. Makes me grumpy .

I wouldn't recommend trying to sand the end of a piece that needs to make a clean butt joint on two planes... you'll round it over unless you have unprecedented sanding skills.

I leave the ungluing questions to the experts. Never used fish glue.

I think getting the tight butt joint to the other strip is going to be harder than ungluing it.
You’ll also need to clean the glue out of the channel so you can get another good glue surface.

To really nail it I think you’d have to cut the binding out w your binding cutter and glue in another one.

If you do want to try and refit you may be able to get one of those small xacto mitre boxes on the binding to try and get a square cut.

To get that section tight next time, if your bend wasn’t perfectly to form, you can use a clamp to span the upper bout to hold it in place, don’t crush anything.

Good luck:)


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Maybe Terry’s mini mitre will help with the cut to length next time? It works well for me.

http://www.kennedyguitars.com/binding-cutting-aid.html

Brad


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I'm with Terry on this for trimming the end of the binding. I do the binding while the box is still in the cradle I use for cutting the binding channel so I have a sort of bridge arrangement to provide a firm surface, level with the top or back of the box, for cutting the binding with a sharp chisel.

Dave

I've only ever used TB, but I don't see why fish glue shouldn't respond the same. You can use an iron or a heat gun, or both in conjunction. I usually don't use water, just heat. But you should be able to trim the end flush, and get a nice joint.

It's a little finicky, but I use a brace offcut with some 100 grit taped on, and go slow, checking often. It can be tricky to get it both straight and square, but it's no trickier than the myriad other tricky tricks we need to do...

To resize your picture, open it with ordinary old MS Paint (not the 3D stuff). Click "resize" and enter a scale factor - 25 will make it one quarter as big. Save it. I took your picture, tried 25 and it was still too big so I resized again at 50 (so it is 12.5 % of the original.



As far as the binding I can't add to what everyone has already said but this is why I pre tape my binding in place leaving little gaps in the tape. When it is PERFECT I wick a tiny drop of thin CA at each gap - it "tack welds" the binding in place. Pull the tape and wick CA all around each seam and bingo! If something needs a little extra coaxing I keep a piece of UHMW handy to push while I squirt some accelerator on the CA.

Thanks for the advice everyone. The water + heat from a clothes iron made it easy to separate the binding to the shoulder. I went with a piece of sandpaper double sided taped to my block plane to sand the end of the binding. I don't think my chisel skills are up for this tbh. It didn't seem to take much to shorten it enough to make it fit. I've reglued with fish glue and have it wrapped up tight with bicycle inner tubes. Tomorrow I'll see how it turned out

Nice! My worry with water is that it will wick into the endgrain causing discoloration, which is why I only ever use just heat...

My version of this works well for me.
I've been using it with a chisel as well as a razor saw.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Nice going. Fish glue can be a little more forgiving in this department so that’s good.

For the next one, to echo Freeman, when I’m fitting binding and purfling I tape it all up first in a dry run when fitting all the pieces together. That way there are no surprises. I do this regardless of the glue I’m going to use. Take your time, tape is cheap, make sure it all fits before cracking open the glue.

FWIW, I use CA now.


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for viewers to resize the picture, in FireFox right click on the picture and choose view image...this puts the image all alone and in the case of large images sized to fit the screen

The repair turned out okay. I'm actually quite happy with it.

There are two issues

1) there seems to be a visible glue line at where the binding meets the side in a couple of spots. Nothing to do with this repair, as it doesn't seem to occur in the places where I de / re bonded the binding.

2) there a section of the purple heart binding that splintered off when I was scraping it flush with the sides / top. It ends up being rounded over.

This guitar is the first I've attempted in along time so I willing to live with few blemishes. That being said I may yet route it off and try again.

Thanks for all your advice,

Stefan

Keep rounding That's nowhere near as much as I do. It greatly increases the comfort factor, not having any sharp edges cutting into your skin.

That glue line really doesn't look worth messing with. Purpleheart is super stiff, so getting it this gapless is already impressive. And unless you're selling to the $5000+ market where you might get one of those people who will literally go over it with a magnifying glass looking for any imperfections, it's unlikely anyone would be able to see what you're talking about if you tried to point it out to them.

You could scrape the side a little bit and scrape the back a little bit to add a little more definition to the rounded over edge, and then break the rest of the edge around the back a little bit to blend it all together. "Breaking the edge" (slightly rounding it) a little bit helps the finish stay on it better as well as making it more comfortable to hold. Not too much - just a little (bit )
If you can find graining pencils you can use them to break up the glue line between the binding and the side. Coloring the glue line intermittently will help it "disappear".
Once it looks good to you don't try to make it look better.

I recently tried a 3mm round-over bit, sanding even more when the forearm sits.
Works well and is comfortable.

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.