Loctite E-20NS 1.69 oz. Cartridge part no. 6430A29 @ $17.29 each at McMaster-Carr
But you will need the reusable manual dispensing gun part no. 74695A71 @ $ 23.76
One of the mixing nozzels part no. 74695A12 @ $ 1.30 ( you can mix these epoxies on a piece of cardboard but you need the gun to dispense it so both tubes move the same amount. ) But the nozzel is nice to use for a job that uses a lot of the epoxy.
The NS stands for no sag and this dries to very good epoxy that will stick to glass and metal extremely well, and really does not sag when it is uncured. It can handle heat and cold. I had some and my mother had a bubble night-light with a glass tube of some kind of refrigerant that came unmounted, and I glued it back on with Loctite E-20NS, and that joint sits above a 7 watt light bulb and it has lasted years and is still fine. The unused tube has a limited shelf life.
Use drugstore 91 % alcohol on good quality paper towels to clean it up before it cures if it gets on anything.
Mark one side of the removable cap with a black sharpie and mark the same side of the tube so if you put the cap back in you do not cross contaminate the tubes.
McMaster-Carr has a special deal with UPS and they get a very low rate, and very fast shipping, and pass that low shipping cost on to there customers.
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You can reuse the gun for many years. The Loctite E-20HP is a great epoxy that sticks to anything ( but it will run ). it does have a limited shelf life.
The Devcon brand is also sold by McMaster-Carr and uses the same dispensing gun, and will stick to some hard to stick to plastics better than the Loctite brand, but the Loctite brand sticks to just about anything including practically all plastics, metals, and glass very very well. And the Devcon brand throws off toxic fumes. Frankly I do not want to have anything to do with the Devcon brand because the Loctite works sooooooo well and does not stink.