Casting "complex" bases

[incenerate101]

Im planning on casting some Dreadnaught bases that i build up myself plans are...
A large circular base a few mm's bigger then the normal 'naught base
Some building terrain such as a wall like the dread crashing through the wall or holding the wall up as he passes by or the dread emerging from a building that was destroyed kind of a thing.

would it be easier if i casted the base and ground seperatly from the terrain pieces? or should i just cast the full completed work.

[Diehard]

It depends. Does it have allot of undercut areas, are you planning on doing a 2 piece mold, are there any parts that are thin of have through holes? If your are planning on doing 1 piece molds then casting in multiple parts is your best bet.

If you are doing 2 piece molds things get a little better but the design can effect this. Through holes limit the location of parting lines in the mold. So you can't easily have a piece with through holes on adjacent sides. For example if you wanted a wall with a blast whole from front to back and a hollow pipe running its length.

Undercuts are also a problem since they trap air resulting in bubbles and miscast. This is mainly a problem with 1 piece molds. In any case you can use pins or small pieces of wire to create vent tubes to allow the air in the mold to escape.

[incenerate101]

It wouldnt have over hangs or anthing (i might add some in after a cast them) but mostly im talking about a base with a crumbling wall that a dread is pushing off of himself like it fell on him or something so i think as long as i leave windows broken and not complete so the rubber can be easily removed.