resin casting tips for a beginner

[uncletony]

You are welcome of course Des, as I said to Keith it is a lot of fun and adds a very useful weapon to your toolbox arsenal.

And though the basics are quite easy I am pretty sure you will gain a new respect for what folks like Ron & Lucasz (dare I add Omega Models?) manage to accomplish.

Cheers

[Berman]

 One point, that I would like to add, is the importance of using a sulphur(sulfur) free modeling clay. Most RTV molding rubbers have a tin base. Sulphur can cause a problem with the RTV curing completely.

[ALBATROS1234]

first of all i must say,great tutorial bo. i really like how you used the lego to cast the albatros landing gear, that way you have many keys to help lock they second part over the mold to the first. this is important. if your keys arent good you risk slippage. i am impressed that you are able to get the suspended part method to work. personally i had problems doing this. i always got bubbles underneath the part, but i supposed on something like that little cylindrical tank it might not be an issue. recently i went to the dentist and i dawned on me that these guys do their fair share of casting and i wondered what they used as shrinkage would certainly be critical in constucting a dental appliance that fits. well he brought me this stuff that i am gonna try and i will report my findings.

[kornbeef]

The dental stuff is alginate I think, only good for 1 use or so I read.

Now I have to source the materials here and find the pennies. I had planned on SWMBO getting me it for Xmas (not romantic I know but tight budgets mean.... )  Anyway seeing as WNW haven't done anything I really desire this xmas I succumbed to a Italeri PT-109 that was on evilbay £30 under list price.

Brilliant info though guys and I appreciate the time you spent on this Bo.All those Umpah Lumpahs must have been on the Pre Xmas weekend party.

Keith

[uncletony]

i am impressed that you are able to get the suspended part method to work. personally i had problems doing this. i always got bubbles underneath the part, but i supposed on something like that little cylindrical tank it might not be an issue.

I've made a few parts this way, so far with good results, but it just might be beginners luck. There are a couple of advantages to this approach as well as trade offs. On the plus side, you don't have to remove the bottom of the box and clay and risk jostling the master from the RTV. I think it is also a bit quicker because you don't have to finesse the edges where your master meets the plasticene. On the negative side, I can see where bubbles under the part might be a problem, and you have to be careful when pouring the first part that your seam is where you want it to be...

[IanF]

MDC sell a resin casting kit. It uses the same stuff they use to make their resin parts. It's a great starting point and they will answer any questions that you have....

[Ronkootje]

When done pooring your sillicone walk to your washing machine and trough in a shoe the set it on spinning the shoe gets it outnof balance wich will fiberate verry fast hold your mold bos on the washing machine this will bring up anny remaining airbubles whenthey do rize blow on them and they will pop.

Ron

[uncletony]

When done pooring your sillicone walk to your washing machine and trough in a shoe the set it on spinning the shoe gets it outnof balance wich will fiberate verry fast hold your mold bos on the washing machine this will bring up anny remaining airbubles whenthey do rize blow on them and they will pop.

Ron

Hehe that's an awesome tip thank you Ron

[Russell]

When done pooring your sillicone walk to your washing machine and trough in a shoe the set it on spinning the shoe gets it outnof balance wich will fiberate verry fast hold your mold bos on the washing machine this will bring up anny remaining airbubles whenthey do rize blow on them and they will pop.

Ron

I use a Lyman vibratory case cleaner/polisher  – the type normally used for cleaning brass rifle & pistol cartridge cases. Holding the article to be ‘vibrated’ against the body of the unit works for most situations but it would be simple to glue a small platform/holder onto the lid as a more elegant solution.

I’m not suggesting it’s worth buying a new one just for casting purposes but second–hand ones cost very little.

Regards
Russell

[ALBATROS1234]

that is a good one ron. i usually just pick it up and down banging on the counter to do this, then pop bubbles with my throw away brush that rise,then repeat until not much comes up. otherwise you get alot of what i call pearls stuck to your finished piece which is nothing more than the voids from bubbles too close to the finished piece.

[Ronkootje]

You can also use your airbrush to pop bubbles BTW.

Ron

[Chris Johnson]

A really informative thread with some ingenious tips. Keep 'em coming!

Cheers,

Chris