Time for an update...this weekend I pretty much spent time with my tank...I love the way it's turning out. Let me know what you think. First, I took it over to the old blasting cabinet and cleaned up the rust off of the bottom. My plan is to powder clear over it and I wanted to have a clean base to start with. I masked off the gas cap hole, the cross over line holes and the petcock holes. The bottom of the tank ended up looking like this:
During the blasting period, I heard something rattling around inside the tank. For the most part I thought this tank was pretty clean on the inside...until this fell out...
I then took the tank up the street to the car wash and pressure washed it inside and out to make sure I got all dust, grime and beads out and off of it. My masking job worked out very well.
When I got it home, I took the sander to it, starting from 100 grit and moving up to 220 grit. I found that the swirl marks didn't really go away at higher grits. They just move around and get a little more shallow.
I then took some 320 grit paper by hand and started sanding along the lines of the tank. This couldn't have been easier. I thought it was going to take some elbow grease to hand sand through the swirls left by the orbital sander, but 5 min later I had a perfect 320 grit grain.
I'm going to finish up the tank in 320 and then move up to 400 wet then 600 wet. After this point I'll decide whether to keep it here or move all the way to a high polish.
Here's where I ended up today. I'm going to try to get through 600 grit tomorrow night.
Cheers!