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Invariably all guitar builders will at some point recognize that there are some very good reasons why hot hide glue (HHG) has been the standard of the guitar building industry for all of time. Examples of instruments that are hundreds of years old and were constructed with HHG exist in very playable condition today.

Although Titebond is a wonderful glue and I believe that we are very fortunate to have it available to us today HHG dries harder, has better acoustic transfer properties, will not creep, and some will say is even easier to use and clean-up.

These days I use HHG for gluing all of my braces, the bridge plate, and the bridge and I am constantly finding new ways to use it. Although I cannot prove that my guitars have sonically improved from the use of HHG I do believe that they have.

An interesting demonstration to perform for yourself is to glue two pieces of scrap on using HHG for one and Titebond for the other. Then take a chisel to the glue residue that remains after removing the scrap pieces. You will find that the HHG residue is much harder, glass like, than the Titebond residue. It is this inherent hardness once cured that provides HHG’s superior sonic properties.

When I was considering trying HHG and asking questions of other builders it all some how sounded very complicated to me. Nothing could be further from the truth and HHG is very easy to mix, use, and clean-up.

The following is the first part of a multi-part tutorial that I wanted to put together on HHG. It has been said that there are a thousand ways to build a guitar there are nearly as many ways to prepare and apply HHG. What you will see here is what is working great for me and something that I could get my head around.

My hope, as always, is that others will weigh-in here in this thread and share with us all what works well for them.

Preparing HHG

The first step is to gather the things that you will need to prepare and use HHG.

My HHG comes from our sponsor LMI and is available in granular form in small containers. The gram strength is 192 which is a reference for the potency of the HHG. This seems to be perfect for guitar building.



A Rival "Hot Pot" makes an excellent heater for the water that will be used to float the HHG bottle in. You will need a thermometer and I use marbles in the bottom of my hot pot to keep the glue bottle from directly contacting the heating element.

I also have the "Crock Pot little dipper" which I bought for use with HHG but mine runs to hot to use with HHG.



My plastic bottles came from US Plastic, you can find them on the web, they are very inexpensive and work great with HHG. I bought them in the 4, 2, and 1 ounce sizes and favor the 4 ounce size for HHG.



An idea that came from Mario is to use a stainless steel bolt in the bottom of your glue bottle. The bolt helps to weigh the glue bottle down so it sits more upright in the hot pot. Another idea that came from Colin is to be sure to degrease the bolt so as not to contaminate the HHG.



To mix approximately 2 ounces of 192 gram strength HHG I mix 40 grams of HHG crystals with 68 grams of distilled water.

Distilled water is used instead of tap water to slow the process of mold that will eventually grow in HHG when refrigerated or not. Once the distilled water is added to the HHG crystals I do not shake the bottle or the HHG crystals that are not yet dissolved will get trapped in the tip of the bottle.









To be continued.......

Welcome back!

What needs to happen next is for all of the HHG crystals to dissolve into the distilled water. Typically I will not use a new batch of HHG until it has been heated once and then put in the fridge over night to help it dissolve completely. This is why once the HHG and water have been added to the bottle I heat the HHG to the 140ish range before putting it in the fridge over night. The next time that I heat the HHG it will be completely dissolved and I can shake the bottle with out being concerned about undissolved crystals sticking in the tip of the bottle.



You can now see that even though the HHG has been mixed and heated it is still not completely dissolved. This is why I wait a day to use it and store it in the fridge for an over night.

Some additional thoughts on preparing HHG.

You do not want to heat your HHG above 145F. I like to heat mine to any thing from 140F to 145F.

I keep my HHG in the fridge when not in use. I have reheated a single bottle many times, more than 10, and had no issues as a result of reheating. I will not use any HHG that is more than a six weeks old and again it's always kept in the fridge when not in use.







Also here is the instruction sheet that LMI includes with their HHG and there is some very useful info in here.



HHG is very easy to use and many users have their own methods of mixing, heating, dispensing, and storing HHG. If nothing else you should give it a try and hopefully this toot will have demystified some of the sometimes seemingly cryptic things that we believe about HHG prior to using it.

Thanks for looking!

Thanks for that Hesh. I've been playing around HHG myself, using the Rival pot also. Haven't tried it on a guitar yet but plan to glue fretboard on neck using it. I am going to put fretboard and neck under a heat lamp before gluing to extend the time I have to apply the glue. Any other suggestion on this?

Thanks again!

_________________
Larry
Fox Haven Lutherie

BTW, I spoke with Frank Ford via email about the temperature when making HHG. He said you don't have to worry about going over 145° along as it's not prolonged. He says that the 145° temperature is for commercial uses where the glue is being heated for long periods of time.

I'm not disputing what you are saying, just relaying what Frank told me.

I enjoy your toots!

_________________
Larry
Fox Haven Lutherie

Larry...I would strongly recommend NOT using HHG for this application. More than one builder has reported neck warping due to the considerable amount of water that is introduced into the neck wood. I personally tried this on my first guitar and had a severe back bow.

Instead, I have been using epoxy ever since and have never looked back.

Best place to start using HHG is on your top and back bracing. You'll be glad you did!

_________________
JJ
Napa, CA
http://www.DonohueGuitars.com

Hey Larry thanks for that my friend! I didn't know that HHG will tolerate going over 145 degrees but if Frank says so that is good enough for me.

Also I completely agree with JJ so you might want to rethink using HHG for fret boards. Back bow from using water based glues does not happen every time but the possibility is still there and it is bound to happen to you sooner or later. I've seen it with Titebond too and it is not a welcome thing.....

I'm wondering about this "FB glueup with water based glue is evil" thing....So far I never had any problems using fish glue for FBs and I also use a lot of it - I spread it on both sides, wait a little for it to soak in, then spread some more (!) and clamp. Never had any backbow but of course only 3 necks is not enough to warrant any conclusion, however hhg has been used for hundreds of years to glue wood stuff blabla etc
Perhaps the backbow issues are caused by warp-prone wood and not the glue itself? Was i a laminated neck? What thickness was prior to glue up? What clamps? I imagine a massive solid caul helps against backbow, and a long 24h+ clamp time.

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Build log

Thanks for that recommendation on the fretboard, don't want that problem. I'll wait a while for HHG on the fretboard.

Here's the email I received from Frank Ford on the temperature of HHG:

"Larry -

The literature says not to exceed 145-150, but they are talking industrial use, with the glue under heat all day. In that use, the temp should be monitored and the glue discarded after a day or so.

I use the stuff by heating in the microwave just before use, and there's no problem up to near boiling. The idea is that it's a combination of temp and time causing the protein to break down.



Cheers,

Frank Ford
http://www.frets.com

Gryphon Stringed Instruments 650-493-2131"

_________________
Larry
Fox Haven Lutherie

I've never used anything but HHG for tops, backs, braces, bridges ect. DON'T use HHG for attaching the fingerboard to the neck. Waterbased glues are OK for this but the combination of heat and water with HHG is what causes back bow problems.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

So is it safe to say HHG is the best to use for tops, including archtops or a solid body with multiple veneers?
And things like neck threw necks?