Re: Iron Man MK XLV 3D Print - Bondo P10
Before I begin, let me state that I like this thread! This thread reminds me why I need to visit the Marvel side more often. You'll have to forgive me, I've been off in "Fallout Land" for some time now...........
Thinned down bondo is nice. By that, I mean it's easy to use, and it's cheap. It is not for everyone, though. So far from what I've read here, sounds like the OP can handle some "rondo", though.
But, before I begin on that, consider XTC-3D. I recently did a Fallout prop that I modeled and printed, and the prints were really clean. I mean they were sharp guys. Now, bondo never touched those prints. I find that really clean prints are best smoothed in XTC 3D. It goes on thin, I even need to use two thin coats. It sands down really well. But most important, you CAN NEVER sand out the resin from in between the print grooves. I've actually sanded rondo treated parts, and some of the bondo will actually sand out of the grooves, causing you to need to reapply. This is impossible with the XTC, which is essentially epoxy resin (so yes, similar epoxy resins will work too) The stuff is cheap, and a bottle lasts F-O-R-E-V-E-R.
The downside to XTC is you can't use it in high detail areas unless you're really good with hand files. I am, so I use it. But others do not prefer to, and it would still be worth it to coat the areas without details and deal with high detail areas another way.
These days, I only use the rondo method for rougher prints. Pillowing, start point seam lines, gaps..........thing like that. I like to thin down the bondo because it's easier to spread and will wet out a little bit. It can be a pain to sand, at first. The first minute of sanding will gum your paper up. Just use an old toothbrush to clean your sand paper, or only use rough and used sand paper that you can just throw away. After the "gummy layer", it's smooth sailing from there. Stuff is hard, but it's easy to carve and use hand files in detailed areas.
To properly thin bondo (just in case you haven't before), just mix a half and half mixture of bondo and fiberglass resin. Use a respirator, this stuff is evil. I use the red cream hardener, not the hardener that comes with the fiberglass resin (you can use either, they are essentially the same thing) so that the red color will show, helping me get the mix even. Just use a double helping of the hardener cream, one dose for the bondo and one for the fiberglass resin. Brush on in thin layers, and doing so in a cooler place will slow the rondo from setting (direct sunlight will speed set time up). Clean your brush in acetone before the stuff begins to set, or it'll ruin your brush. Rinse and repeat.