More Small parts casting

I recently bought a couple model Flak gun kits to scrounge for parts. A 1/48 scale and 1/35 scale German 88mm GunFlak 36/37. I selected the parts I wanted and modified them so I could mold them with a one piece block mold. This meant back filling any gaps, holes and bridges, anything that would allow the molding rubber to get into or behind. Parts were then glued to a piece of .5 mm styrene and enclosed on each side with my LEGO blocks. The advantage of doing this is of course unlimited greeblies. I can now add as many as I want without worrying about running out.

Selected parts.

Set up ready for molding. I used OOMOO 30 for this mold.

Over night in the pressure pot and great results. I also cut the back off a tank model and molded it as well. I'll place it under the YT-1000 between the engines.

I used Smooth Cast 305, it has a longer pot life and requires 30 minutes to set, allowing more time to pour and for bubbles to be crushed in the pressure pot. 



I just dribble the Smooth Cast into each cavity and seal up the pressure pot. Even though the casting material sets up in 30 minutes, I recommend you leave it in the mold overnight. The cast may be set up, but I find it's still a bit soft and can easily be deformed by handling it.

IMPORTANT NOTE: When molding and casting this type of mold, it is very important that the molds are laid out perfectly level inside your pressure pot or on your work bench. If not you will end up with a wedge shaped mold as the rubber sets up. Then when you set your mold up to cast, the casting material will flow to one side and you will not be happy with the results.

 

The cast parts are perfect and bubble free. All I have to do is cut away the overspill and sand the back side of each part.

Perfect copies.

I'm really impressed with how this part came out. As you can see it's only 34mm long and you can see that all the details of the part are cast with no bubbles.