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I bought the current Hot Pot Express to make into a glue pot. The newer model did not look like it was going to regulate to a low enough temperature, so I did a little modification to the innards. Moved the contacts a little and it works fine now, http://www.pbase.com/schnitz/piano , pictures 14 thru 23. Just make sure when done, that the silver contact it not touching the middle contact. I monitored my progress with a B&L binocular microscope, but a hand lens should be enough, and a hair dryer on low to see the contacts switching.

Nice!

I did a similar thing with an individual deep fat frier from Wilko and an old jam jar - not as neat as yours, though!

The problem with today Babe hot pots is that they boil then shut down. May be they can be modified as well.

I think the temperature range over which the Hot Pot turns on and off depends on the distance of the silver tab to the upper copper contact. You can see in my picture here, http://www.pbase.com/schnitz/image/151028314/original , that the separation is very small, less than the thickness of the metal of the silver tab. The pots sounds like it is going to boil, but never really produces anything like a rolling boil. So, the temperature range of the outer water bath varies about 5 degrees F, and less for the glue temp.

To lower the temp, in addition to all I have noted above, I also made the opening in the lid, 1.5 inches instead of 1 inch, to give more ventilation to the bowl of glue, increasing the temperature gradient from the thermostat to the glue, to produce a lower glue temp.

This isn't something that is going to appeal to a professional who needs to be efficient, as time is money, but for the amateur who really does not want to invest in equipment for an on again - off again hobby, this is just perfect, and I can make tiny amounts of glue at a time, which works well for my action repairs.

Yes, good solution anyway. SOme hide glues (all ?) are supposed to be "cooked" a little, that mean heated a little more after the jelly have grown a few hours (may be up to 75°c but just to dissolve it and get rid of any impureties that goes up the surface.
)

But today quality glues are very clean, they are made by industrial gelatin makers, so I guess most can be used as they are. If any whitish foam it can be left aside.

As long as the glue does not smell bad it is good for use. I add a few drops of "conservateur" a product to avoid foam. A little urea can slow the gelling time, but I usually do not need it.

Keeping a low enough temperature (55-65°c) and cover the glue pot is enough for the precautions. ALso make a new batch for precise work and never allow the brushes or wood stick to stay in the glue when cold.

I have 2 superb glue pots Herdims, with a rheostat.

The resistance burns on them, I changed it more than once but at the moment I am alittle depited. SO I use my big US made glue pot who never failed (but was made with an aluminium inner recipe which make the glue black and is not considered good).

Can you add another vessel, a jar or bowl, for the glue so that the glue is not in contact with the aluminum? Then add water in the aluminum pot to make it a triple boiler like I did.

I use it directly, without water, but with a smaller jar installed.

I am unsure but I guess that if water is added the glue pot is a hair not strong enough (it should not, probably, thats just me)

As it is intended to be used without water, it does not seem to suffer from that.

ALl the best

Pictures moved onto a separate page, http://www.pbase.com/schnitz/glue_pot .