by mangozac » Thu Jun 23, 2011 10:39 am
Case in point is the Cadian sprue above. It will have been made using a single part split mould.
Now it seems there are two schools of thought when it comes to building moulds: build them expensive and long lasting or cheap and limited life. Most of us home and low volume caster opt for the latter.
A single piece model with a relatively dynamic pose is probably going to need a two-part mould, which required a lot of playing around claying up the model to create part lines, etc. Not to mention the time for two silicone pours, mucking around with release agents and stuff.
If the model is broken up into relatively flat pieces like that Cadian above you can mould it using a single part split mould. Simply mount the parts to a block, stick it to the bottom of a mould box and then pour in the silicone. Once the silicone it set pull out the block and use a sharp knife to split the mould. For full instructions check out my . So the split mould can be made really quickly and easily. It has become my technique of choice now that I don't have any particularly large parts to cast. Mould alignment can be an issue but there are tricks to minimise that.
Perhaps it is a mater of personal taste. Are you planning to be doing the production yourself (at least for a little while as you get things going)?
Oh yeah I can make that....