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Binding gaps are driving me Nuts. Most recently I started at the waist and worked out. Even using superglue the waist binding shifts up leaving a gap
At the base of the binding. If that gap is corrected then the gap is formed on the face/top. No matter what I do I can't get rid if both. I love the look of ebony but my god, it's difficult to work with. How do I overcome this issue?

Now I'm using cotton clothes line. Last time I tried hemp line. No bueno.

Did you ease the bottom edge of the binding? It sounds like your binding is rocking in the binding channel.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

If you are using a domed top and deep binding it is harder to get good results compared to using more shallow binding. Before binding you should look your rabbets over very carefully. I use visual aids. Make sure there are no humps or bumps, sharp chisel and small file work for this. Also before binding break the inner lower corner of each piece of binding. On the bottom edge of the binding I like use a scraper to make sure the angle between it and the outer face is a bit less then 90 degrees. These two things help make sure the binding will fit tightly into the rabbet. You say you are roping and I find this is the surest way to get the binding tight. It also is understood you are bending the binding as close to it's shape as you can. Hope it works out.
Tom

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A person who has never made a mistake has never made anything!!!

Not a great pic but it's a good 1/16 gap between binding and side

Yes this is exactly what is happening. A+B= -C
-A+B= C

Not sure what to do. The ebony binding is .54 thick. I thought it would be easier to work but now the vertical is the problem.

Flippo will probably chime in and say I am staring at the binding- and he would be right. However, I cannot tolerate these minor mistakes; I just need to know how to correct/prevent them.

I'm no expert by any stretch of the imagination, but I just finished #3 a prewar/1937 spec D-18 and I used Ebony binding and its my best job to date. Bent 5 pieces and ended up with 4, used the brown binding tape Stewmac & LMI sell. eased the inside corner on the binding and the diagonal opposite (Trevor Gore tip lets you get the tape tighter and not tear) I used titebond extend, looks like you need a lot more tape mine was overlapping on the inside curves and the upper bout.

Joey,

I believe your problem comes from the blue masking tape you are using. It doesn't stretch well enough (or stretch back, provinding sufficient down force). If you really want to use tape, use the Stewmac binding tape, of standard strapping tape. For myself, I use 3/4" wide elastic bands. They take care of the gaps real well!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Good article in GAL abt controling unmanageable binding of domed tops .Think it was summer issue. I use whatever works vln clamps, blue tape white tape rubber bands, upholsterers cotton tape(rope). fb glass tapes wooden cauls for the waist longer clamp for the block ends. For those who want to make their own .The violin clamps are made by Condit . They have inside and curved profiles on 2 sides which makes them very handy for binding guitars /ukes with tight bends.

Break the inside edge of binding.
Wrap with long approximately 1/4 inch wide rubber strips cut from truck tire inner tubes, installing little wooden sq blocks 1/4 inch x 1/2 to 3/4 inches long that have been waxed to prevent sticking to any glue.
This method will help in closing up the top gaps. Sometime me haz to wrap the same block 2 or 3 times
Small clamps will help close up the sides gaps.
This is a slower process and therefor suggest a white glue because of its longer open time.

In this pic of you can see the blocks holden the 1/8 inch holly purfeling up snug while the glue sets. Actually it was right after these blocks stuck to the purfeling that me made and waxed the ones me first described. Then the rabbit and the purfeling will be cleaned with a chisel scraper and sanding blocks like the one below before process is repeated for the outer banding.








Be happy you are only binding a simple S curved rabbit.
In my work the binding edge is a compound curve ~ as much as 1 1/2 inches rise or fall along the face of the rib, which causes the banding to twist leaving gaps. Then my top and bottom plates are not flat nor are the ribs...translates to a real hassle cutting that rabbit and in getting the binding to snug up on both the sides and the edge...the little blocks applied under the rubber and the clamps help.

Sometimes the banding me using is 3/16 thick and up to 2 inches wide which is prebent to one profile curve and then scribed cut and fit to the other curve to avoid gapping from twisting.

Hope this helps.


blessings
?adma

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Finger: I understood from your first post you were roping your bindings........??????? But I see blue tape in your picture.......???
Binding is .54 thick....???? Did you mean .054" thick...? Your bindings look a bit tall. Did you reduce the width of the binding by the amount of the purfling that was added....? Suggest you try roping your bindings without glue to see if you can get them tight.
Tom

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A person who has never made a mistake has never made anything!!!

I think Tom has the answer. The taller the binding, the harder it is to get it to bend around a compound curve without leaving gaps. For this guitar, I would get it tight on the sides with good tape and then clamp it at the waist.

For future guitars, going with narrower (not as tall) binding will help a lot.

Also, a technique I saw Tom Doerr use is to profile the sides before bending, tape the binding to the side and bend both at the same time. This helps set the compound bend in the binding during the bend, before you try to glue it in.

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http://www.chassonguitars.com

Lots of good advice here. Others have done far more than me, but here is what I think for what it's worth.

If you have a gap at the bottom of the binding on the side of the guitar, likely a couple of things are in play here. One is the angle of the bottom and side of the cut being different than the same angle on the binding itself. This can easily be caused by the tool cutting the channel without you even realizing it. This can be adjusted by sanding/scraping the bottom edge of the binding to match.

For another, be sure (as has been mentioned already) to cut a chamfer on the inside bottom edge of the binding. This can be easily done after it is bent. Darn few (if any) corners are a true sharp 90 degrees, and the bit used to cut the channel is no exception. It will have a radius, even if only very small. So make some relief for it on the banding itself, easy to do and it won't show anyway.

From the second picture, it looks like the binding is taller than the groove. This is fine, because it will be scraped flush after glue up. But, be careful here, because the act of taping / banding the binding in place can cause it to tip toward the center of the guitar, opening up a gap on the side. That might be all that is wrong here. If so, you can address it as you go. Start with a clamp across the side to hold it tight for the first section you glue up, that will help and at least get you started out right.

As for the blue tape, I also use it, but not as an only clamp. It is used simply to hold the binding in position while getting the real clamps in place, be they tubing, rubber bands, beam clamps, etc.

So don't give up. I know this is frustrating, but you'll get there. Just start by holding the binding in the channel, and if it won't sit with no gaps on either edge, then you have an angle problem to investigate. If it sits good but pulls when clamped, then clamp differently.

Good luck, hope this makes sense.

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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."

Usa a rope for the binding....

What does that mean?

I think he's saying to ease the bottom inside corner and the top outside corner.

One thing I do is to take a short section of binding about an inch long and check some of the problem areas like the waist and around the upper bout just to make sure the channels are cut correctly. I will also run a V gouge around the inside corner of the channel to remove any splinters and such left over from routing.

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Steve Smith
"Music is what feelings sound like"

jfmckenna, I think he talks about chamfering the corners of the binding that a) sit against the inside corner of the binding rabbet and b) the "outside" corner of the binding, which can cause binding tape to tear if its too sharp and you try to stretch the tape over it.

Lots of good advice here already, I'll just add that with wooden bindings I find I get better results with water based glue than CA. For one thing, it causes the wood to swell ever so slightly, thereby closing minor inconsistencies, and if they don't close, you can sometimes chase them down after the fact, with water, heat and pressure, and fix things further. Actual gaps are tough though, in most cases its probably better to do it over than to fiddle around like that. Binding jobs go a lot faster the more practice you get .

Tip: Unless you have ebony with lots of color variations, its quite difficult to tell it apart from plastic, once finished. Just saying.

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Rian Gitar og Mandolin

I have a love hate relationship with ebony binding and I use it on about 1/2 of my builds. You can not have enough tape. My method is to press the binding down into the side while stretching the tape against the side, I then transfer the force pulling into the top and stretch the tape and attach to the top/back surface. I use regular titebond thinned about 10% with water and if there is a small gap after tape removal some localized heat and a clamp will pull the gap closed and I wick in some thin CA to hold it. My worst area is the waist and cut away areas, but a round cawl and clamp after taping pulls it in tight. If I think there might be a problem in an area I double or even triple the tape. I have done a couple armrest bevels with ebony and it is a real pain to get tight along the side area but it can be done.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Lots of great advice here. Sort of off subject but here is some more tips that I had to figure out the hard way. If using binding tape it's good to provide a bit of extra protection for the top. Since spruce (and cedar, redwood) is soft the tape can tear out slivers if you're not careful, especially around the tail and above the soundhole. Before glue up I put on a couple coats of shellac, and lessen the tack of the tape by sticking it on my jeans a few times. When you go to take off the tape, soften it up with a hair drier and pull it off with care.

Mentioning binding I use a 1 lb cut shellac 1in from edge on back an sides to prevent tearing from blue/white tape.

Ok I see, thanks.

Shellac is a very good idea if using tape so as not to tear top fibers as well. If my bindings are not bent perfectly then I will use cotton sash chord to pull it real tight. Otherwise I am a big fan of the tape and thin CA method.

Ahh yes .054", I should not have had that last beer watching football at the bar! I tape them in place with fish glue and then wrap with rope. I would really like some rubber but I haven't had any luck finding any locally. As for the height I had a bearing fly off my Diablo flush cut bit which gouged the side. Origianlly it was 2-3mm shorter. I had to make them taller out of necessity.

I get good results using strapping tape for gluing, with Titebond I or similar, but it requires a coat of shellac or other sealer on the top because of its aggressive adhesive. Also, the binding, even pre-bent, is usually being forced into a vertical curve that is usually not addressed in the bending. Put a vertical bend in the binding when bending and it gets much easier come time to glue the binding on.

Pat

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

Joey , find a bike shop nearby ask them for their worn out inner tubes which are thrown out. I /ve reused bicycle inner tubes by slicing them lengthwise with a st edge an craft knife, usa box cutters.

Bike inner tubes are not near as strong as car inner tubes and truck inner tubes are the thickest and the strongest. Depending on what is being glued determines which me use. For troublesome banding, me much prefer the truck tubes and me don't mean your pickup truck variety. Get tubes from an 18 wheeler rig. Very very strong for closing up gaps.

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