Colored epoxy help

[Jeffrey Cole]

I need some help with colored epoxy. I would like to fill in some knotholes with colored epoxy. I have never done this. What brand of epoxy do you recommend and what do you use to color it. I hear of problems with bubbles. Any tips will be very helpful.
Thanks for your time!!
Jeffrey

[Mark Kornell]

Pretty much any brand of epoxy will do. If it is a nonstructural application (like filling a knothole), the 5-minute stuff you can find just about everywhere is perfectly fine.

For coloring agents, lots of options. Pigments, sawdust, dyes, etc. Just don't use too much (10% by volume or less) as an excess will inhibit the epoxy from curing properly.

You might be tempted to go with something black, but that usually looks unnatural for filling a knot hole. I use a brown pigment, but I've read about others using finely ground coffee to achieve the same effect.

To deal with bubbles, apply a.bit of gentle heat. A.heat gun on low, waved in the general direction. Some use a propane torch as the heat source. (But don't light the wood on fire!) Avoid too much heat, as that will cause the epoxy to cure too quickly. And avoid too much air movement (hair dryer), as that will cause ripples to form on the surface of the epoxy.

[David Hawxhurst]

depending on the depth do multiple pours. the last pour should be the thinnest which will allow the air to escape before the epoxy cures. as stated above heat works well to remove air, i use a propane torch. for color i personally use transtint. depending on what i'm work on will determine the color i use. for fun i like to do things differently and use blue or purple color.

[Yonak Hawkins]

It probably goes without saying, but you must use a dry coloring agent. I use dry pigments from artist suppliers in both epoxy and Bondo. They're very concentrated so it doesn't take much.

[Steve Baumgartner]

What I've done to prevent bubbles is to first apply a sealer coat of very thin epoxy (thin both in the sense of layer and in the sense of viscosity). I think the bubbles happen when air in the pores is pulled into the epoxy. I've used Transtint pigment to color the epoxy.

[John TenEyck]

I, too, often use Transtint dye to tint epoxy to fill defects. It works great and you can make any color you want. Transtint, being a liquid, thins the epoxy a little, too, which makes it easier to pour into the defects w/o trapping air bubbles.

John

[Jeffrey Cole]

Thanks for all the information. Some of you mentioned thinning the viscosity of the 2 part epoxy. What do you use to thin it. How do you mix it with the epoxy?
Do you also mix in the Transtint dye when you mix the 2 part epoxy together.
Jeffrey

[John TenEyck]

I mix the epoxy first then add the Transtint dye. I little goes a very long way. Transtint will thin the epoxy, too. I've never intentionally added thinner, and don't know what an appropriate one would be.

John

[Jamie Buxton]

There's two kinds of epoxy I see in the stores. One is the 5-minute stuff. It is the consistency of toothpaste or so. I think it would not fill in holes very well, and any air bubbles would stay stuck in the cured material. The other kind of epoxy mixes up to the consistency of pancake syrup. It flows well into holes. I use West Systems, which I get from a local chandlery. System Three is pretty much the same stuff. Woodcraft sells it.

+1 on Transtint.