So as I said this was simple. I used the 1/4" x 1/16" Disc Magnets to ensure they could hold the weight of the finished HB or HF sponson of my Baal Pred. I measured out the distances needed inside the hatch here to make sure the magnets had actual contact in both situations of a door or a sponson. With the one magnet on the hatch itself and the other on the sponson, they had full contact and were spaced perfectly! Now for the door, I needed a spacer to make up the distance to the magent in the recessed area. I snipped a piece of sprue, filed it down to the width of the door and tested it: perfect again! With the sprue spacer and the size of the magnets they had full contact and perfect spacing. I started by using the rounded GW file to remove the rivet from the center of the inner rhino hatch to provide a smooth surface for the magnet to adhere to. Applied a dab of super glue and let it set.
Next I decided to magnetize my sponson options, eventho I feel I'll never A) use HF on my Baal Pred and B) never field a normal Pred that has las-cannons as an option, I still felt like I want the option or maybe something would change come next BA codex. This was a bit more tricky trying to decide how I wanted to mount it. I contemplated using Oni's method but I wanted to retain the up and down tilt of the guns for some reason, don't ask me why. So what I did was just cut above where he did to leave a bit of the arm that sits between the two gun halves. For this I used the 3/16" x 1/16" Disc Magnets. In general, go with Oni's method. I would too, but if I switch now, they won't all match up and I'm OCD when it comes to stuff like that, lol.
(Click for closeup)
As for the other parts of the Rhino like switching out for a Whirlwind, Rhino doors up top, Pred turret, and the little hatches I decided that them being on top, I'd just let gravity do the work of holding them on. Trying anything else would be too complicated for all the options. Next up will be my Land Speeder, with magnetized options for the missile launchers, MM or HB and the HF or AC underneath. Should be a bit more of a challenge. Then will be my Heavy Weapon, Special Weapon, and Sarge in my tac sqaud.
As a general update, I've also started priming everything that I finish in Krylon Primer Gray. This eliminates me from trying to decide between priming in either white or black depending on the model as I have the full foundation paints and I wholly endorse them as a base paint, so the primer color is almost a moot point. Plus the can is labeled "primer" so it's gotta be right for the job, no? And it's only 3 bucks at Wal-mart and it has the angled nozzle so you can do passes in wide lines instead of a centralized circle.