Keeping hide glue fresh

[Bob Gleason]

I use hide glue mainly for bracing, on new instruments, crack repair on old ones, and a few other tasks. I go through the routine of refrigerating it at the end of the day, and if I'm not using it the next morning, I leave it in the fridge. Of course, that means, and it happens often, that the glue is not ready when I want to use it. I end up running back into the house, heating up some water in the MW, then heating the glue in the MW. Not that it takes long to do that, but it is an interruption. A lot is said about storing the glue properly to extend it's life. Today I saw a video by Dan E. where he says he just leaves the glue in the pot on the bench for several weeks and keeps using it. A few weeks of glue life would be fine for me. If that is an O.K. option, I'm very ready to do that instead of the daily refrigerator or freezer ice cube thing. I'd be interested in hearing practical experiences from other hide glue users. 

[Bob Gleason]

Mark--Thanks. I'll give squeeze bottles a try. Seems like, the freezer might always be the place to store HHG. Does not take much longer to heat up a small quantity, frozen or unfrozen. If the freezer keeps it longer, seems like the way to go. 

[Paul Breen]

By coincidence, there is a current thread over rat the MIMF ( Musical Instrument Maker's Forum for those that don't know) with some discussion on this exact topic.

Todd Stock chimed in and gave some good basics for hot hide glue preparation, use and storage. He also talked about factors that degrade hot hide glue. Most folks are aware of things like mold, freezer burn and over heating but I have never heard that each time the glue is heated, you lose some tack. Todd claims 10%, which is a substantial amount of degradation, per heating. I went on-line and tried finding references to re-heat degradation. There is plenty of information on prep, use, storage and mixing ratios vs glue strength with studies and charts but I only found two references siting degradation from re-heating. Neither gave any information supporting a 10% loss per re-heat or any other rate for that matter, just stating that is does occur. I responded back asking where he got his information and he responded back, Milligan & Higgens, a hide glue manufacture. I have not tried contacting Milligan and Higgens to verify the 10% loss rate claim but it is enough to know that decline does occur with re-heats and for important glue work, best to start fresh.

Here is the link to the discussion at the MIMF:

http://www.mimf.com/phpbb/viewtopic.php?f=13&t=5081

[Bob Gleason]

Paul- Thanks. I just sent a few questions to Milligan asking about the loss of strength after reheating, freezer burn, etc. I'll post answers here if they answer.--Bob

[Bob Gleason]

Paul, Talked to Milligan this morning. Here are a few points I asked about. Nothing earth shaking, but still interesting to hear it from the manufacturer. Probably, most of the glue you might buy under any label, comes from them.

1. Heating- They say that as long as you don't go over 160 degrees, it does not degrade from being heated. It is also O.K. to thin it with water and mix in a film that may develop during the day.

2.Freezer storage should last a very long time, but still possible to degrade it if bacteria are present. A batch should last 2-3 weeks with refrigerating it at night.

3. I asked about viscosity. My method is to thin it until it runs off the brush in a steady stream, not lumpy or in individual drops. They said that was a correct viscosity.

4. Their main concern is cleanliness. Wash everything, and use clean water. If the glue darkens a lot or smells, toss it out. Common sense!

[jbbancroft]

It's good to hear the glue companies response. There are many rumors about hide glue usage, that is false information. Best people to talk to about hide glue usage is long time violin repairmen that use hide glue exclusively.
Jim

[Paul Breen]

Bob, did you ask about glue degradation with each re-heat? I have been freezing and re-heating several to many times as normal routine and am inclined to believe what Todd Stock posted about tack loss with re-heats over at the MIMF. He also stated that prolonged heating degraded the glue's tack as well.

I am a bit surprised at their 160 degree heating limit. A 140 - 150 degree range is what you will most likely see when searching the net. I keep my glue pot set between 140 and 145 and there are times I have the pot blissfully cooking all day. I have frankly never noticed a problem or had work come back to me from hot hide glue failures due to extended heating or re-heating.

[Bob Gleason]

I did not specifically ask about the degradation from reheating. I did detail my process of reheating it everyday for a couple of weeks and they did not see it as a problem. I'll ask again. They were pretty specific about not going over 160 degrees. My intent here is not to say that what others are doing is wrong. I just like to get as much info as I can on subjects that interest me. I have included a link to a very subjective little test that I did on glues last year. Everything we do is subjective, so what the heck. I write monthly articles, more than  a hundred or so by now, for the local uke guild. Not because I think I know a lot, but because no one else will do it. Some things, like my glue pot have changed since I wrote this but here it is just for fun    http://www.pegasusguitars.com/a-subjective-glue-test.html 

[Bob Gleason]

Link in my previous post is not active for some reason. If you decide to look, copy and paste works.--Bob