03-12-2010, 04:37 PM
(03-12-2010, 12:41 PM)bwayne64 Wrote: Wow, thanks guys. I knew I was in the right place,Sure thing, Joe. This is what we're all here for. Unlike some snob forums, we are proud to share our reference when we're allowed to,and our knowledge with each other humbly in the spirit of giving in order to further the world of creativity. We're proud of our members' work, and we're also proud to be the latest modeling forum on the internet. Although we're not high tech talkers - our experience makes up for all the CGI computer geeks the world over! We're true artists that aren't stuck up with a high, and mighty attitude towards those of us who aren't as adept as we are,or those who are just begining this hobby. Remember - when your hobby becomes work, and no fun, it's time to leave it. This is why we try to maintain a friendly atmosphere without pressure.I'm going to start casting soon, when the weather is right. It's good to know that the molds can sit for a while and still be usable. I have plenty of space to store them. If I borrow a rare kit or part, I can make a mold and have them for a while. Thanks for the great info guys, Cheers,
Joe
With reasonable care, these moulds will last their lifetime of casting. You just want to ensure that these don't dry-rot. Without being lubricated, they lose their suppleness, and they break down exponentially. They need absorption of the main component - silicone to keep the surface soft, and pliable. This makes for a better,and more reliable casting. This keeps surface defects like warpage, out of the cast parts. The thinner the wall of the mould, the more silicone spray it'll need to be supple. Meaning, it'll need to be taken care of more often than thicker silicone moulds will,but they all need this care periodically, just thinner walls will be less resilient to warpage,or weighted objects laying on top of them.
Keep in mind, all things need maintenance to keep them like new. You can't help the fact that these will wear out eventually,but if you take care of them, they'll last longer than those who don't. You might get 10 more casts than someone who neglects to spray these. The only ones who don't are those who do production types of projects that only last a month, or so. This means that someone who makes more than 50 of a certain part will use these until they're no good anymore,because they're in constant use, so they'll reach the end of their life span sooner than someone who only uses them occasionally.
Most producers make more than one mould if they're going to make more than 50 - 60 parts per run of a single part. One way of getting around the 50 parts problem is some people will make a gang mould where more than one, or two parts are made at once. This saves time,and it makes parts faster, it also saves silicone. For example - a batch of ten parts made from a single mould used 10 times to make a ten part mould can be used 5 times to make 50 parts. Always wait for about 10 - 15 minutes for large parts to cool, or they'll come out warped from the heating of the resin. These will need to cool before being removed as this too, may cause the mould to distort from being handled with hot resin in it. I don't know how many people are going to make moulds for more than that, but this should give you all you need to know about mould durability.