Travel Mug Epoxy

[Jed Hefley]

Howdy folks,

I recently turned a batch of stainless insert mugs, and had a funny thing happen. After epoxy set, and I filled the mug with coffee, I heard a popping sound. I assume the epoxy is reacting with the heat from the coffee.

If this is so, do you guys have a recommendation on a better epoxy to make my product better?

Cheers,

Jed

[Al Launier]

Ice coffee? :D Sorry, couldn't resist.

[Paul Williams]

Heat will soften epoxy, but I believe it takes more than you would get from coffee. I also can't think of what would make a popping noise if the epoxy just softened a little. Did anything let go or fall off? Is this a staved cup or turned from one piece of wood? What was the epoxy used for? Sorry about the questions, but you got me curious. All my cups have been turned from one piece of wood and I have had one or two crack with use. I assumed that it was because I didn't use kiln dried wood.

[Jed Hefley]

The mugs are both, staved, and segmented. Popping from both. The epoxy I used was the cheap 5 minute kind from the local box store. I turned all of them to 1/8" wall thickness, and applied a quarter sized amount of epoxy to the side walls of the stainless, and seated it in the wood. There are no cracks in the wood whatsoever. The popping only lasts for 1.5 seconds or so.

[Paul Williams]

Is it possible that it has nothing to do with the epoxy. The heat causes the air between the steel liner and the wood to expand. The top is constrained by being fastened to the steel liner, so the wood itself bends causing the popping noise. It is a strange one Jed. I hope there is at least one other poster who has experienced something similar.

[Jed Hefley]

Good call. Pending any trapped air spots, a weep hole in the bottom should alleviate this, I think. I'll try that.

[robert baccus]

The SS metal will be affected by heat but not the wood or epoxy to any significant extent.

[Mike Nathal]

In Malcolm Tibbetts article in 2007 American Woodturner, he recommends silicon adhesive to glue the insert to the wood at the top. He also uses Gorilla glue on the entire insert surface, after it expands it acts like an insulating foam. I have followed his practice and I don't hear any noises.