Painting and Filling

posted Jun 3, 2012, 11:41 PM by Andrew Stock   [ updated Jun 3, 2012, 11:41 PM ]
I started out with some blank strips of aluminum scrap that I had laying around... scuffed, marked, dented... time to fix em up, so I can use them to see what the paint looks like, and so I can get my painting techniques right:

I started by sanding the blank sheets down with some P400, to get rid of the marking, scratches, and such, and to give a good grip surface for the primer. The standard blank is on the left, and the sanded one is milky/solid, on the right. Ready for priming!

I primed in light, even strokes from edge to edge, waiting two minutes between coats (as per the instructions on the can. I used Self Etching primer, as it provides better adhesion than standard primer when used on aluminum and other metals:

(without fail, a hair landed on it right after I finished the final coat. )

I took a bunch of scrap wood laying around and threw together a quick drying rack for my pieces and parts, too. Crude, but effective! I'll probably use it to hang parts for priming and painting, too, so I can get all the sides on each coat, cutting down on the number of passes I have to make on each piece:

After the primer dried for 15 minutes (per the can instructions), I moved on to wet sanding using P1000. I know, the grit was a little high (the can called for P450, but that seemed low). Just meant a little more elbow grease, but a smoother finish in the end:

Next, after letting the primer dry for a few hours, I broke out the paint. I grabbed a few random colors at the local hardware store... just to see which one I ended up liking more:

(I was originally thinking of making my case Black/Blue... but now I am leaning towards Black/Black... so the blue paint is more for fun at this point. :p)

First coat, using a highly scientific method of propping the subjects up on spray paint caps on top of a cut up cardboard box. 

The finish came out pretty well, for a first coat. Just goes to show that a good coat is all in the preparation. Still a little splotchy, but I think additional coats will clean that up:

I really like how uniform the matte black came out. Highly considering a black/matte black combo for my case right now:

While waiting for the paint to dry, I decided to do some additional light reading on spray painting for various finishes. Many recommended warming the cans in hot water prior to using them. The difference in how easily the paint applied / how uniform it dried was astounding. Needless to say I'll be soaking all my paint going forward. 

I started the next coat by sanding it with P1500, getting a smooth finish and clearing off all the dust/hair/bugs:

Another few coats... looking pretty good so far:

Next step, clear coating! Still waiting for this coat of paint to dry though... so that'll be in the next update!

Moving along... I did some experimenting with patching up holes in aluminum. I have two fairly large holes in the midplate of my case that I would like to fill... but I've never tried anything like that before. I picked out a piece of my case that I didn't plan on using in the final design, and I decided to give some Bondo bumper repair a try, just because that's what the supply store happened to have handy:

I started out thick... basically just trying to fill the holes. After a few botched attempts, I decided to use the screen stuff that came with the bondo, to see if that would help. Man, it worked wonders!

After waiting a few minutes, it just peeled right off leaving the holes roughly filled. 

I gave the patches another quick coat of bondo to fill the holes and imperfections, then cleaned it up to get it as flat as I could, knowing what was coming next:

... Sanding!

... and more sanding!

Finally, after 30 minutes of assault with P80, I had all the excess removed:

I then went over the whole deal with P150, to remove some of the excess scratches in the aluminum:

Another painting tip I learned... prop stuff up standing up, rather than laying down. Helps cut down on the drips and splotches, as the rattle cans seem to like spraying forward instead of down:

Primed, and ready to dry:

Whew... what an update! Next time... more painting, and some Acrylic work!