I did my first attempt at marbling. I like the looks of the color scheme but have a problem with it drying. After 24 hours it is still tacky. What is the likely culprit and what can be done with it? Do I have to remove it and reapply or is there something a little less daunting?

Adding pigments to epoxy can affect them. One of the ways they're affected is that the cure time is often increased. Give it a couple more days and then see how things are progressing.

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Mark,

Like Tom said, more time could solve your issue. You may also try increasing the temp of the room your rod is drying in.

For your next marbling project, try giving Jacquard's Pearl-Ex dry pigments a try. They do not change the properties of the epoxy, and in my opinion look better than most paint pigments: they have a metallic sheen.

Take care,

Chris

Also when you do it next time stir/mix resin thoroughly then add pigment and stir again. Most curing problems are due to the fact that they are not mixed up enough. When I have done it in the past the pigment I used was powder and Testers along with the mud additive that keeps the colors separated and it dried faster.