u/halon1301

I printed and painted this helmet, for a finish I figured rustoleum ultra 2x gloss clear coat would work well, I did several coats, but some of the paint is easily scratched. The base is pla, sanded with 120, then 220 grit, painted with woodfiller, sanded with 220 again, primed with rustoleum ultra 2x, then painted rattle can and acrylics. Finally I finished with 7 coats of gloss clear coat.

I'm thinking of now scuffing it and doing a water based polyurethane finish, as it may be harder. My biggest concern however is damaging the paint, specifically the acrylics. What grit of sandpaper should I use? AI is saying 220, which seems a little too aggressive.

If I do polyurethane, I'm going to be brushing rather than spray, and I'll likely go satin finish.

To start, I'm fairly new to Fusion, but have been working with onshape for about a year and a half, with tinkercad before that. Definitely not an expert, but understand all the concepts.

I have a model I'm making of a gauntlet. I have done a projected extrusion to get the shape, but the edges of the extrusion have undesirable angles. In the attached picture, the box is around the face I want to change. I'd like that face to be perpendicular to the face of the extrusion, or the primary body.

Any suggestions on how I can make that happen?