Bsyamato,
The diorama was started as a "fun" project to display our Gundam kits at public events. The base is a piece of 2'x4' (610mm x 1219mm) plywood, with urethane foam landscaping. It is 1/144, so we were able to use N scale Kato buildings for decoration. The buildings and MS are not glued down, so we can change the arrangement at will. In fact at Kawaii Kon, the guys played around with the mobile suits to make comical scenes on the day I wasn't there! Sorry about the horribly out of focus photos - I think the guys were laughing too hard to hold the camera steady.
The "explosions" are crumpled up aluminum foil over wire armatures. I think we covered them with something - spackle maybe? CA glue? House paint? Not sure. We added to the diorama each time it appeared in public. The first time out it was an asteroid surface, the second time it was a forested area, and the third time it was a city. The 2006 Kawaii Kon was its fourth appearance, so we added the explosions. We allowed non-UC models onto the diorama because one of the guys helping out wanted to use them.
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