I'm not sure what software you are using but in Wings when I subdivide a couple of times I get these indented bits on the bolts. With the bolts I think you need control edges close to each of the corners, or just hard edges surrounding the parts that you want hard(you dont need to put hard edges on a flat surface within…
Question for you, now this seems to be a rather technical piece of hard surface, also it looks like your working on the objects local system instead of the world. Do you use snapping a lot or do you mostly eyeball your elements?
small updates: I finally got my base high-poly finished. There are some details around the cap piece that I left out after botching the model like 5 times. I really want to re-re-restart this mesh, but I gotta keep moving forward if Im ever going to finish this thing. I think the HP looks decent, but overall Im not too…