The problems here are that you are trying to do things that are not intended for the epoxy.
First:
I understand that many folks have tried to mix all kind of things with epoxy to color it....with a variety of results. The problems arise in the fact that a lot of things aren't soluble in epoxy. Other things may affect the cure rate and final hardness of the epoxy. Use only dyes that are made for epoxy resins and you will have no trouble with this part. These dyes can be purchased at any supplier who sells epoxy and fiberglass. Some knife suppliers sell them ,too. I highly recommend the dry powders sold by K&G. The small jar will last most makers many years. Cost is $7, IIRC. I use a flat toothpick to pick up the small amount needed to dye a medicine cup of resin.
With all due respect to those who posted earlier, paint and ink are bad choices for epoxy dyes.
Second:
Some people try to thin the epoxy with heating it and the tube. This will work in moderation, but also affects the cure rate.Warming the resin to 80-100F is OK, heating to 200F is not. Too much heat can also result in the resin never getting hard right. The answer is not to try to make the epoxy thinner, but to use a thinner epoxy. The stuff in the tubes at the hardware store is made to be thick and not run. The stuff in the small bottles at the woodworking suppliers and fiberglass repair places come in a variety of viscosities....some nearly water thin. These are usually harder and smoother resins when cured,too. I think
SYSTEM THREE CLEAR COAT is tops here. Woodcraft supply sells it in a 12oz. kit for $24. This is a super resin for doing paracord handles, too, BTW. It also has a long shelf life, over two years. (Generally, try to use epoxy resins within one year of purchase in most cases)
Third:
Making the epoxy thinner by adding all kinds of things that will dissolve it is counterproductive. After all, many of these thinners are used to
break down the epoxy bond. You don't want anything that has even a trace of water as a thinner. Alcohol and even acetone are not good for the job (despite the prevalence of their use). The only thinner you want is either a thinner marked "for epoxy resins" or a high volatility lacquer thinner.
Read this:
Here is an excellent article on this subject by the folks who make epoxy. Take two or three minutes and read it. I think it will answer many of the problems people have with epoxy.
http://www.seqair.com/skunkworks/Glues/WestSystem/Thinning/Thinning.html
Last:
I know I always seem to come around to this (as does a certain metallurgist who I won't name, but his initials rhyme with KC), but -
Don't just do something because I ,or anyone else, say "Do this", "I do this", " So-and-so does this".....!
Understand what is happening in the chemistry, metallurgy, physics,mechanics,etc. of any project will end with better results.....and you will have a better understanding of how to control the results.
You could post a thread that says ,"How do I...." and spend hours reading and posting back, getting twenty different ,"It worked for me" ideas.
OR, you could google ,"Thinning epoxy", Using Epoxy", etc. and read the real information in ten minutes. The results? Under the
post it system you might get the job done just fine, but wouldn't necessarily know if it was right or wrong, and may not have any idea how to change the process to apply it to other tasks. In the
research it scenario, you will gain some knowledge, and the ability to use it in many ways. It might be the nerd way to do it, but the leaders in any field, including knife makers, generally are the ones who have done their homework. A good example is that ,if you read the article I suggested above, you would learn that warming the scales prior to epoxying them on the knife will greatly improve the bond. How many of you knew that....honestly?
Stacy
