Wednesday 22 July 2009

Drop Ship XXIII

Progress on casting!

I've poured the two part rubber molds for the engines, tail plane, landing gear and cockpit and am waiting for the rubber to cure. Fingers well and truly crossed.

The single piece mold for the Engine Mounts is complete, and I've cast the first set of pieces from it.

The results are a little mixed.

On the plus size there has been no change of shape, so the gear which enables the multiple placement of the engines still works well and fits snuggly, and I'm able to get the resin out of the mold without any problems.

On the down side I'm clearly suffering from some problems of trapped air. especially around any sharpe corners in the master. I expected this somewhat as I am casting these items without using any kind of de-gassing chamber or pressure pot; however the number of bubbles is a little depressing.

On the models I'll make for myself I can rectify this by filling and sanding after I've cast them but the idea of selling these is looking remote now as the quality isn't there. I'll have to investigate cheap methods of making vacuum chambers and pressure pots.

Anyway It'll be tomorrow before I'm able to make the first casts from the other two piece molds and for the first time assemble a full drop ship.

Wish me luck.


  1. The bubbles must be frustrating! When I used to do this, I used to stir the rubber, in the mould after pouring, and bang the mould on a hard surface to help shake the bubbles loose. But presumably a vacuum chamber would be more efficient.

    Will be very interested to see the finished piece.

  2. Thanks for the comment BigRedBat.

    I do bang the mould when i pour the resin but its also pretty fast setting (5-10 mins). I do get air bubbles rising to the top, but they are getting caught on the edge of details...

    I'm going to try 'painting' the inside of the moulds with resin to get it in all the details before i pour the bulk of the resin.

  3. Ahh I thought bubbles were in the rubber. I never cast resin so have no experience there.

    I wondered if it might be worth casting the feet in low melt metal? No bubbles and quite strong.

    Cheers, Simon