Some Questions About Using G/flex Epoxy

[Kirklands]

I have had a couple of problems using the West System G/flex 655 and System Three Black Epoxy Pigment. First, there are tiny pits in the repaired material; second, the repair seems to be more vulnerable to teeth marks than vulcanite.

My process has been to thoroughly mix the epoxy, add a few drops of pigment, apply to the stem, and let it dry at room temperature for 24 hours. I use a file, 400/600/800 wet-dry sandpaper, and the 9 levels of Micro-Mesh pads to shape and finish.

These are my first attempts at using epoxy, so any advice you can give will be appreciated.

Here are some pictures of the repairs. The first two are the front and back of a stem; the third picture is of another stem and shows the teeth marks after I smoked it just a couple of times:

 

[TheIronMonkey]

I wonder if you are introducing bubbles as you are mixing the two parts of epoxy and those tiny pits are little bubbles that you’ve sanded open. I don’t know if placing the mixture on a vibrating surface (i.e., something like a motor or compressor) as you combine the different parts will make the bubbles rise to the surface and pop—I have done this when casting resin in silicone molds, but am not sure if mixed epoxy will benefit from this technique.

@georged has much more experience with epoxy and might have some advice or pointers for you. Good luck!

 

[georged]

Yup, those are bubbles.

Bubbles can happen if epoxy is cold when mixed, no matter how much you stir. Even if it's a type that will cure in a week at cold temps, cold MIXING will result in micro-sized Swiss cheese.

Put the containers in a ziplock bag and then into a container of warm water for a while before using.

Also, all epoxy has a shelf life, and will start acting wonky in several ways when it gets too old.

 

[Kirklands]

Yup, those are bubbles.

Bubbles can happen if epoxy is cold when mixed, no matter how much you stir. Even if it's a type that will cure in a week at cold temps, cold MIXING will result in micro-sized Swiss cheese.

Put the containers in a ziplock bag and then into a container of warm water for a while before using.

Also, all epoxy has a shelf life, and will start acting wonky in several ways when it gets too old.

Thanks, georged. This makes sense, and I'll definitely do it next time!