Good job Larry on finishing your speaker cabinets! Using Epoxy to seal the porous MDF material is a good idea. They look very nice. Do you plan to leave them with just the Epoxy finish or do you plan to spray paint them with like a black lacquer finish?
Ron
Thanks Ron... I am doing many things different than the norm such as rounding over all edges instead of only a few. I want a different look. I think I could have even done a 3/4" roundover.
The epoxy is a sealer only, and the boxes will be painted. I will be doing 1-2 more rounds of epoxy with a goal of sealing/burying all seams. I may even use a narrow strip of light weight fiberglass (.75-1 oz.) on all seams, but that's getting carried away for sure.
I have to be careful what I use for final finish. Lacquer doesn't play nice over epoxy as lacquer thinner dissolves epoxy. There is probably a transition primer that would work.
I really like marine enamels over epoxy. The one I use can be brushed, and looks like it's sprayed on. I do like the piano black look, but I don't know if I want to do that much work

I have been kicking around the idea of painting the boxes a bright color such as red, yellow, or blue with black speaker stands?? Any thoughts are welcome...
Something I could have tried, and I will try on my stands which are MDF as well is to stain the MDF with black water or alcohol based Analine dye or even just India ink. I will then seal the MDF with epoxy tinted with graphite (2-3) coats, and finish with just a clear such as automotive clearcoat or varnish. The dye/india ink would be the colored basecoat. The tinted epoxy will seal and bury the seams. The clearcoat or even varnish will seal, protect, and give the final sheen I desire. Sound like a plan??
I am open to suggestions................
Larry