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I was remembering the last time I used hide and the stuff I had in a a jar took a real long time to heat up. Kind of soured me on it's use because I don't have a lot of time to waste waiting for it. I remembered I had some fresh hide in a yogurt or some kind of plastic cup in the freezer so I brought that into the shop one night and I couldn't believe how fast it melted. Have any of you seen this phenomena where glass slows the heating process? I like glass because it's heavy but unless there was something wrong with that batch of glue, I will use plastic in the future. Am I wrong again?

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Hutch

Get the heck off the couch and go build a guitar!!!!

Well, heat does move slower through glass than it does through metal, but I doubt that explains what you experienced. How did you heat the glue?

I don't want to evangelize, but if you had a bad experience once or a few times, maybe that was because of some factors that you can change without too much trouble, and then have a good experience.

I love working with hot hide glue, and believe me, I don't like wasting my time. If you go about it a certain way, it can be very efficient.

I usually only use a little at a time. Even a plastic medicine cup is big. They sometimes tip over in the water I had in my wax melting thing. I found a tiny pie tin at a garage sale. They had a bag of them and they gave it to me. I mix some glue up, and.put it right on the metal bottom, no water. Melts in no time at all, doesn't tip, and if I do take it out, the tin stays warm a long time
I thought that the water idea was slow.

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Why be normal?

I use little plastic squeeze bottles. Heat a pan of water on the kitchen stove because it's faster than waiting for the glue pot to warm up. Ready to go in just a few minutes.

Haven't tried glass, but I don't like open topped containers because the glue dries out quickly.

I use a rival pot with water.

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Hutch

Get the heck off the couch and go build a guitar!!!!

There are a number of ways to prepare hot hide glue for use, as well as different ways to apply it. I have settled on mixing a fresh batch every time I use it, mixing less than 3 ounces per batch, which is the capacity of my double boiler glue pot. By the time I get the hot plate going, the water from the tap hot and the water bath part of the glue pot filled up, the dry glue has been saturated with the water I put in it. Within 10 minutes of sitting in the water bath, the glue is liquid and ready to use. I spread it with a brush; fingers in hot hide glue make a huge mess (for me, anyway). I can vary the amount of water that I mix with the dry glue, to either have thick glue or runny glue. I can add urea in varying amounts to slow down the gelling of the glue. This all gives me a lot of flexibility that I wouldn’t have if I made large batches and froze little bottles (which I used to do). To each their own. I love this way of doing it, but some folks would not. Having a good double boiler glue pot is key to what I’ve described.

I don't think the speed of heat transfer between plastic and glass would be that much noticeable. There must have been something else going on there. Could be that as mentioned above the large open jar dried out. HHG with less water in it probably would take longer to heat up.

Like Don above I prepare it in many ways too. For things like peones or braces I mix up a fresh batch and brush the glue on right out of the pot. For things like gluing on the top or back I make a batch of liquid hide glue using salt to extend the working time. I keep a batch of that in a little squeeze bottle with 3 small stainless steel nuts in it so that the bottle sinks to the bottom of my water pot.

But frankly if time is of concern then just use good old Titebond. I find myself using more of that for this very reason.

Ok, you've all given good advice and I'm going to change my approach to only using fresh batches made on the spot with the appropriate amount for the job at hand. I have to try that salt thing as well.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Weight of the container - really mass - matters, as does the material. It will take more energy to heat a glass jelly jar to 145 deg F than the glue in the jar, and the lighter/lower the mass of the glue container, the quicker the contents will heat.

- An 8 ounce volume jelly jar half-filled with HHG will tip the scales at just over 11 ounces, while an 8 ounce volume LDPE Boston round will weigh about half that. Both container and glue need to be heated, and heat only moves so fast through any material (conductivity).

- Glass moves heat about 200 times slower than aluminum for a given mass of the materials, with LDPE much closer to glass in terms of thermal conductivity than aluminum...this is why glue pot liners are either copper (best) or aluminum (better).

Have hours to kill? Take that 8 ounce glass jar half-full of glue from a 35 deg F 'fridge, place it in a room temp glue pot liner filled with water, then plug in the HoldHeet. Presto! 45 minutes later, your glue may be getting close to usable temp.

Not so interested in waiting? Keep the HoldHeet on during shop time (it never gets much beyond 160 degrees), pre-fill the liner with 140 deg F water from the tap (you needed to clean the pot anyway...we did every workday), and pre-warm the glue for 30 seconds in a 1500 watt microwave. Most of that zappage will be warming a portion of the glue to 110-120 deg F, which then warms the glass (glass does not have the 'handles' present in water which allow those microwaves to jiggle things around). Instead of warming pot, liner, water, jar, and glue from room or fridge temp to 145 deg F, the 90-95 deg glue jar goes into 150 degree water and in 10-15 minutes, you'll be ready to go.

Another work flow suggestion.

We kept a Rival HotPot cooking at around 170 deg with clean water for glue clean-up. From a cold start, the Rival could boil 10 ounces of water in well under 10 minutes. I would plug in the Hold Heet, clean the liner at the sink, fill the Rival with 24 ounces of water, then plug the Rival in next to the HoldHeet (remember to dial back the Rival to maintain the 170 deg temp). I would put the glue jar in the Rival directly from the fridge, and in about 15 minutes, pour off some water from the Rival to the HoldHeet liner and transfer the glue jar over. 20 minutes after that cold start, I was ready for hide glue work without running any risk of over-cooking the glue in the microwave.

Another idea: do your prep on the work piece as the glue warms. For bridges, we would get the 315g glue moving, then do the final clean on the bridge patch and bridge. Ready to glue once the bridge warmed up to temp needed for 315g.

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For the times they are a changin'

- Bob Dylan

I have a hot pot that will boil a small amount of water in a couple minutes. I then pour it into the metal removable liner of the wax warmer I use, which heats up the liner and cools down the water. I use small plastic applicator bottles for the hide glue which I place in the wax warmer. When the first one starts running low I'll put another one in the pot to warm it up. Using multiple small bottles for the small amount of glue I use at any one time cuts down on the waste of throwing out "old" glue.