I have used MDF again to achieve a complicated layered octagon picture frame. We made a unique MDF build up about 6 months ago on a different project.
Raw MDF sucks up material and needs sealing. I wanted a super smooth, high gloss paint finish that would look a bit like molded plastic.
Frame one - about 2' x 4': Wood working went quite well. Thought I grabbed the shellac based sealer, but had the water based urethane. Proceeded with several coats. Sanded to 220. Painted with Rustoleum high gloss black spray cans. This paint says to recoat within 1 hour or wait 24. After 24 hrs had a beautiful finish, but decided to give it a light rub out and one more coat. Disaster - crinkled all the coats extensively all over the frame. Sanded completely and reperformed with outstanding success.
Frame two - 54" diameter octagon: Made sure I had the shellac this time. Careful job of sanding all edges, etc to 220.Multiple coats with sanding between coats again to 220. Nice finish on full length pieces, then cut the octagon sections, cut spline slots and biscuit work, glue and assemble. Sand any and all imperfections with 3M superfine sanding pads. Man this things looks good. Spray mist coat with Rustoleum High Gloss spray can(s) and continued mist coating on a 30 minute rotation until good color and finish on all surfaces ending with a "full wet coat". Looked really good, but that high gloss sure points out minute imperfections. Honest 24 hours. My partner decided to give it one more light sanding - nice look and feel, but without gloss. I wasn't there, but he shot one more coat and we have a crinkled mess again. We will get this, but it sure is frustrating.
Any help?