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So I only recently switched to using HHG. I am struggling a bit still to apply the glue and get it clamped before it starts to gel. Specifically thinking about braces here. My current procedure is to heat the HHG in a bottle to 160 degrees. I then apply it by squeezing it from the bottle directly to the brace. I then spread it with my finger, place the brace on the top or back and then apply go bars- one on each end and then work toward the middle with the go bars. It always feels like it is gelling before it is fully clamped and the glue line is thicker than I would like often times. This is 182g HHG by the way. Any advice on how to improve my method would be appreciated. Thanks.

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Chris, I put the braces in the microwave for 20 seconds before applying the HHG and installing. Takes a bit longer per brace, but it gives me a lot more working time. Same for bridges.

Bob

I always like to hear the pieces of wood with a heat gun first. Sounds like you are doing a good job since you have a lot of squeeze out. If you get the brace glued and clamped within a minute or a minute and a half you're good.


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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

Hear?...... I meant heat .... Lol


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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

I think 160 degrees is too hot, I think the recommended temp is 140 to 150.

I use one of those small crock pots with aquarium gravel in it with a little water. then I put a small jar with glue in it directly in the gravel.

When I am ready to use it I use a small stiff paint brush to apply it. I place the brace and then slide it forward and back just slightly until the glue starts to grab. Then I place my clamps or go bars on and the part doesn't slip around. I have not had one fail yet.

This idea comes from piano repair guys who usually don't clamp parts in at all, they just slip them (or whatever it is called) and when they move on to the next part.

I do heat up places were I can't get the parts together quickly like neck joints or bridges but not braces.

I have done a number of experiments with slipping a joint and not clamping it and it is quite surprising how strong they actually are.

Bob

I lay out a heating blanket on the bench top and run around 160 with a surface thermometer. Lay the braces on the blanket and heat the top with a heat gun.

I just run a generous bead of glue down the brace with the bottle, don't bother to spread it out.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I use an Electric table warmer to warm braces (turn them over until well done) - pick up an old Salton (or something similar) of a suitable size in a yard sale/ebay.
I find a heat gun needs a third hand....... (I do have one!!)

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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.

At a shop temperature of say 19/20 centigrade you shouldn't have a problem gluing a brace even without pre warming it. Perhaps the glue is a little too thick? It should barely take 1 minute to apply glue, position the brace and then clamp. Of course pre warming will give you plenty of headroom but you should be careful that heating a piece of wood too much can alter the woods surface.

Skip this step. Just apply the bead thick enough that you're still getting squeeze out even though you're not spreading.

Have your go bars in place pressing against the top right next to their final locations.

So, you just apply the bead of glue, set the brace in position and then move the go bars over to the brace.

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I clamp stuff with go bars. I like to use a few of those aluminum shield shop lamps with a heap bulb in it. Point a few of those at the go bar deck, and it/s all nice and warm for gluing.

"This idea comes from piano repair guys who usually don't clamp parts in at all, they just slip them (or whatever it is called) and when they move on to the next part."

Hi Bob,
I've heard that technique called a "rubbed joint". By rubbing the joint you squeeze out the excess glue and get a thinner glue line. The quick tack of hide glue allows the pieces to stay in place until the glue dries. I believe Mario Proulx mentioned, that as hide glue dries it pulls the joint tighter.
I've glued a bridge or two (and several other things) using this method and had good luck with it.

Apply generous bead, then brace, go bar. After squeeze out has gelled, peel it cleanly off return to glue bottle for reuse.

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I use a recycled hair dryer.I put 2 thin coats of 192 HHGon the brace, but iam using cam clamps. I then remove the clamps cleanup the exces hhg and check that the braces are holding if not I reclamp and reheat the brace with the hair dryer . HHG glues back on to itself temp is regulated with a garage sale candy thermometer in the water bath .Glue should drip /drip off your brush. too thick or too thin doesn/t work . Keep mixing the hhg every hr.if too thick add a dab of water too thin add hhg.Keep temp at 140-150 for best results. The longer you use hhg the better you will get at controlling your desired outcomes.

Thanks for all the replies. There are some really helpful tips here.

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Apply a bead of glue to the part, and clamp it. Don't bother spreading it. It saves time, and a thinner layer of glue will cool much faster than a taller bead. In no time, you'll know what size of bead to apply to which parts to achieve just a bit of squeeze out.

Grumpy got me to use this stuff. I never had luck with the bottle method and use the same method Martin used and uses to this day. I use a glue brush. It takes less than 3 seconds to glue and apply the brace.
I use a go bar. The glue brush is the one from tools for working wood.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

And I tried brushing and it takes too long for me.

Point being, try various methods and find the one that works for -you-.

I have to give Grumpy credit for getting me to use HHG. Not personally directed at me, but I kept reading his posts with his method, hints and suggestions until I got the confidence to try it a real guitar. I am so glad I took the leap.

After I dry clamp a brace in place, to find all the correct length go-bars I need, I put a couple of 1/4" blocks in place with go-bars, to give me something to line up the brace. It also helps keep it from sliding when I put the brace in with the glue on it. Then I lay the brace upside down, in place, on the sound board and heat the brace with a hair dryer. This heats the brace and sound board surface at the same time. I then apply a thin bead from a $1 hair dry bottle found at Walmart and clamp it in the go-bar deck. Be sure to remove the 1/4" blocks immediately after gluing or the squeeze out will glue them in place. Don't ask me how I know that.

I used a laser thermometer to check the surface temp of a brace after heating, and then timed it to see how quickly the brace cools down. This is not necessary, but I had the laser thermometer for other purposes and wanted to know how much time I had before it cooled. I use the laser to monitor the temp of a side during bending, a fretboard or bridge when I am heating it for removal.

James

How about how to apply HHG when gluing a fingerboard to a neck. Most of the time I apply the glue and get the board in place with a rubbed joint and then heat the board with a heating blanket to reheat the glue and then clamp. Anybody have a better way to do this so you don't have to reheat the glue?

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one big advantage is you don't have to be neat , this stuff cleans up like magic in a few minutes. Learn a technique that works for you.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Gently warm both sides of the fretboard and the Neck surface. Not hot, just a gentle warmth. Wet the upper surface of the fretboard. Apply glue to the underside of the board. You will need a fairly wide brush, 1 inch or wider.
I use the actual Nut blank in position, spot glued. That acts as one end stop. I have 4 softwood tabs glued to the side of the fretboard which engage the side of the Neck. With such a set up you don't need to position the fretboard, it's effectively self locating. Make sure the tabs are glued on well, you don't want one of those popping off.
Fretboard caul is at the ready, as are the cam clamps. Should take less than 2 minutes to apply glue and get all the clamps on.

The fingerboard is one of the few places where I don't use hide glue. Instead I use Smith All Purpose Wood Epoxy. I don't like the idea of introducing water into the neck, as I take great pains to ensure the glue surface remains completely flat throughout the neck-shaping stage. That's why I don't attach the fb until the neck is fully rough carved -- the wood will continue to move and twist until the internal stresses are released.


Ken Jones
Mountain Song Guitars

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I use fish glue for the FB from L/V I tested a sample outside for 1 month. The fish gives me ample time to line everything up dble check my measurements to insure it/s allright then go ahead. I have the epoxy too. But reluctant too use it becuase . i think it releases a lot sooner and at a lower temp than fish . But I could be wrong .One must do their own testing.

My process:

1. More water in the glue so it squeezes out of the large contact area more easily.
2. Heat both surfaces (I use an open flame on the stove)
3. Apply water to the outer surface of the fingerboard to equalize expansion and prevent cupping.
4. Apply glue to the underside with my usual squeeze bottle, spread it with a finger, stick it down (with position pins through two of the fret slots), and squeeze around a bit to make sure the neck surface gets fully wetted as well.
5. Apply lots of cam clamps as quickly as possible.

I used to use a caul, but nowadays I just stick the clamps straight on the board. Faster, and even with position pins it can try to slide slightly out of alignment, which is hard to see and correct under a caul. I level the board and fret on the guitar, so no big deal if it curves a tiny bit. I've been getting really good invisible joints since switching to this method.

I did try fish glue on one as well, and it worked fine, but my tiny bottle ran out and I haven't bought more yet due to the various horror story threads I've seen about it. It's also extremely sticky and annoying if you get it on your fingers (although it washes off easily)

Dennis chicken littles screaming about the demise of fish glue, are just one or 2 persons experience. I bought a pint of LV fish glue 2 years ago and it works well for everything that I/ve tested. Sometimes you can get a bad batch of any kind of glue, fish , hhg, titebond , etc etc.