I always thin my epoxy to make it flow. I use a product called epoxy reducer, made for spraying. I used to epoxy spray swimming pools, used 1 qt reducer to 1 gal of epoxy. I used to buy it by the case from a company called Seamco in Florida. I'm sure you can find a similar product available for the hobbyist.
In fact I think I saw epoxy reducer in one of the catalogs, maybe Moore's Lures.
Good Luck
