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So, I'm in the midst of putting finish on my #8 guitar, and a topic that is on my mind is the avoidance of "too thin" bindings. You all know what I'm talking about: You do your best to refine the sides before cutting the binding channels, so that the bindings won't be too thin from further refinement later in the process. But further refinement seems to be necessary, so while the bindings are not hopeless later on, they are thinner than you wanted them to be.

I swear, I thought I had this under control this time, but I still wound up with a few spots where the binding is skinnier than I wanted.

I am developing new plans for what I do, and when I do it, before I start #9, in order to avoid this problem from now on. I hope they work. In the meantime, if you have any suggestions on how to avoid this, I am all ears.

Here is my revised plan:

I will rolling-pin-sand and hand refine the sides pretty well before I cut the binding channels. I did that this time.

I will cut the binding channels either exactly the right size or just a hair deep. That way I can sand the sides down to the binding, instead of sanding the binding down to the sides. I did that this time.

I will put a layer of masking tape all over the sides after I cut the binding channels, but before I install the binding (I use silicone rubber bands instead of tape to glue in bindings and purflings). This will keep glue from the binding process from sticking to the sides, which it turns out, is a significant cause of my need to refine the sides after the binding is installed. This is a new strategy.

I will not use any power sanding on the sides after the binding is installed. Power sanding has great potential for being too aggressive in spots, which leads to the need for more refinement. This is also a new strategy.

As I said, we'll see if these new precautions help keep the binding as thick as possible. Thanks for any suggestions along these lines. I am clearly a slow learner when it comes to this particular issue, so any help would be great.

Don,

You use hide glue for bindings, is that correct? What is "a hair deep" here? I found that even with CA glue use I had to take it down 0.0015 below on the test block I use to test the binding fit, and even then I still had areas where the binding was flush with the side. I would think with hide glue it would need to be more than CA glue? Might even be worth testing some glueups in a block just to see where it's really landing. I too thought I had it figured out and the last uke I built proved me wrong.

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How thick are the bindings you use when you start?

Do the bindings end up uniformly thin all around the body or only in spots?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Are the binding rabbets perfectly complainer with the sides?

Pictures?

Brad--

Yes, I do use hot hide glue for the wooden bindings. You are probably right; there is more swelling with the hot hide glue than with CA. However, that water eventually goes away. I'm OK with the binding being a little proud, due to the swelling. I can afford to lose a few thousandths. The real problem for me, I learned from #8, is that I need to protect the sides from the clean-up needed after gluing in the binding. That takes way more material off than fixing the swelling problem. Binding is the sort of job where I can't get to the squeeze-out to clean it up before it dries. So, it is a hardened mess under there when I take off the rubber bands. The upside is that the binding is beautifully tight from the rubber bands; best binding I have ever done. I think the masking tape is a good solution to this problem. Cleaning up a lot of dried hot hide glue takes its toll on the sides, I've learned the hard way.

You have a good point, though; I can probably go a bit deeper with the channels to better offset the swelling. But, the swelling is not the biggest dragon I'm trying to slay.

J--

The bindings start out about 0.080" thick. I wind up with thinner and thicker sections, instead of it all being uniform in the end. And I know how I get there: Too much messing with the sides after the binding has been installed.

Michael--

Yes, I cut pretty good binding channels with my LMI tower and body carriage. They are as parallel to the sides as can be reasonably expected. And I round over the inside corner of each binding strip.

I'll have to provide pics some other time. I'm at work at the moment.

When you sand the sides after the binding is installed, what is the method you use? Do you draw witness lines on the sides so you can monitor the progress of your sanding?

If you look at a spot of thin binding say on the top binding and then go straight across the side to the corresponding spot on the back binding, is it also thin there or not?

_________________
Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

J--

I'll talk about the most recent guitar (#8), rather than a longstanding established procedure. I'm still learning, so I don't have a set procedure.

I had a lot of dried hide glue to clean up. So, I did some scraping, and some sanding by hand. Some of the stubborn spots I tried the rolling pin sander. It worked well at sanding the glue, but it was probably too aggressive in spots. But the scraping was not leaving the best surface on the sides, either. Dry hide glue is tough stuff. I think I need to just not let it bond to the sides; hence, my idea of masking off the sides before I glue in the binding with the rubber bands.

For your second question, I think the top and back bindings have equal thinness at some points, and unequal thinness at other points. I probably tilted the rolling pin sander, or over scraped one side or the other. That is definitely something for me to watch out for, and one of the reasons I want to avoid power sanding after the binding has been installed.

The witness lines are a good idea; I will add that to my preventive measures.

I just tape mine in dry, then use my fingernail and test if the binding is flush. If not, I work that area of ledge slightly deeper with a file. If I get it right all the way around dry, they stay the same thickness after glue .
I’ve never understood why folks use hhg for things that won’t need removal in the future. But whatever works I guess.

I was wondering if tilting of the pin sander might have something to do with it. Witness lines can help avoid that.

I don't know if this would be relevant to what you are seeing, but I don't do any spot sanding on the sides before or after installing the binding. I always sand across the whole width of the side with adhesive-backed sandpaper on either a block of 3/4" ply (about 6" long) that has been checked for flatness with a straight edge or a tube with a diameter of a little over 1" for the waist bend. If there is a spot along the binding where there is more excess glue to sand off, sanding it down using a block that spans the whole side keeps it all flat and reduces the chances of over sanding into the binding on one side. Witness lines help with this too.

I install the bindings just slightly proud (~0.003") of the sides and then sand them flush sanding across the full width of the sides. I know some builders like to install the binding slightly below the sides and sand the sides down to be flush with the bindings, but I hate sanding and don't want to level sand the sides twice.

_________________
Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Your sides need to be PERFECT before you route your binding channels. Any discrepancy will translate directly to your bindings. Allow about 0.003" for swelling of the glue - so you want to cut your binding channels that much deeper.

I like to let my bindings dry for a couple days before I start sanding the body. Put some pencil marks on the sides and stop sanding once you hit that mark. I like to 80 grit to get everything almost perfect and then switch to 120 grit to get the surfaces perfect - then lightly go through the grits to 220. Rolling pin sanders are great just be careful not to let them dig in. I use them to remove most of the glue but always finish up with a sanding block.

Again, the important part is to have your sides perfect before you begin your binding process.

I'm doing pretty much what Jay is doing. Key is to make sure the bindings fit just very slightly proud then install them. I level with a scraper then finish sand with a wide block. If parts of the binding are a bit thinner then rounding over the edge can help that blend in.

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Steve Smith
"Music is what feelings sound like"

Give the box a coat of shellac before cutting the binding channel. Use bits of wet paper towel to rehydrate large glue drips and they come right off.

Sand the inside corner of the binding.....and I use dremel and drum sand the binding flush......

We can talk about that, but really, hot hide glue is not the issue. Any glue can leave some schmutz on the sides, and I would rather it be hide glue schmutz than Titebond or something else.

Dennis--

I'm curious about the second suggestion. Have you seen that work out with the kinds of junk that gets left behind after a binding job? I could rehydrate the dried glue, if it doesn't cause more problems that it solves.

On the first suggestion: Do you think the shellac coat would work better than just masking off the side? I go to the masking approach because I use it in other places on the guitar where I might be a bit liberal with the glue.

Yep, I've got the inside corner trick down, Doug.

Any special trick to grinding the binding with the Dremel without taking larger bites here and there?

This is one of my fav subjects. Binding (and purfling). I like my end result to be recessed a few thou. I have no issue using a ROS to settle it. Or a scraper (Caruth). Using a ROS, I avoid the binding. Low speed. Take your time. Mix it up with hand sanding. BTW, I apply my purfling in layers using a hot iron and dried Titebond. So much easier. And cleaner

Yep, many times. This is one of the biggest advantages of hide glue for this job. Once the big lumps are removed, then switch to wiping the whole thing with a wet paper towel to rehydrate the rest of the residue and remove it. Try not to let too much water soak into the actual glue line, but don't worry too much about it. I make the bindings a bit oversize, which creates a little fillet of glue that acts as a buffer before the water starts soaking down into the seam.


Not sure, I haven't tried it. Might be an improvement, or might be more trouble than it's worth since you still have to deal with the top/back and any glue drips that run past the tape.

Don; Regarding dremel/drum sander...........I use the 1/2" 80 grit (or 5/8"?) drum, good pair of glasses, and sand sections...say 3"-6" lengths, focus on the waist too, ....when the glue residue is gone, we're down to wood only. then, I hand sand 100-220.....this only works if the binding is proud of the sides......

As Toonces said, get your sides 100% before cutting the channels.

The tape might be a good trick but I’d test it first. Often thin fluids will soak right underneath. It would be quite the job if your hhg simply ran underneath and glued the tape to the wood...

Myself, I cut .070 channels, and .073 bindings. I prefer to sand the bindings flush...

Tape works good with HHG, TiteBond and Epoxy, at least 3M 233+ that is pressed down works good cause I use it all the time for that.Tape does not work good with CA, the CA gets under it and then you have to scrape the tape off too

_________________
Steve Smith
"Music is what feelings sound like"

Same here, Steve. I'm not at all worried about hot hide glue seeping under the masking tape. I tape off all the time with other gluing operations, where I know that I am prone to go a bit glue-happy. It saves me a lot of clean-up work. I'm actually a bit surprised I didn't think of this before.

They were. Then I made them noticeably imperfect as I was cleaning up after the binding job. That really is the stage that went screwy on me. All before that was on target, including the depths of the channels and the smoothness and flatness-across of the sides.

Have you tried scraping clean with a scraper or razor?


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This sounds like good discipline, J. I'm definitely going to be more careful about this. It makes total sense; the sides start out thin, and the binding is pretty much the same thickness as the sides. I have to avoid any tilting toward the top or back, because there is just no room for allowing, then fixing, unevenness. Sanding all across the width at every moment is slower, but it is the better path to the real goal. Along those lines, it is just too easy to tilt any power sanding device. The rolling pin sander is great (with care) before I install the binding, but it is too easy for me to tilt and dig an uneven spot after the binding is in place. I have the zeal of the converted.