15 September 2012

WIP: Resin Cast of Milliput Spaceship

Yesterday I posted about my first epoxy putty scratchbuilt spaceship, a simple design sculpted with Milliput Superfine.  Today I went ahead and pressed the relatively flat design into a block of sulfur-free sculpting clay (I can't remember the brand name) to make an impression mold.

I detailed the mold with ball burnishers and other regular shapes, then poured some resin in.  I removed the cast and cleaned up the edges with a little wet sanding.  I'll still need to sculpt the exhaust section on the back and put an antennae cluster on the front, but it's coming along.  I plan to paint it tomorrow if I can get that detailing and the basing done.

Not as crisp as the master...

The resin cast is nowhere near as crisp as the Milliput original, as far as panel lines go.  The resin gives a number of advantages though.  First, with the impression mold I can add globular tank features that would be too hard to sculpt, as well as little greeblies to catch the drybrushing.  Also I can jam little pieces of plastic into the clay, extending into the cavity.  These end up getting caught in the cured resin and when removed from the clay jut out of the cast spaceship at right angles, forming easy and convincing looking struts, solar panels and radiator fins.  This little wedge ship has one such fin, but it's hard to spot in the picture.  Finally, the biggest advantage of the resin is duplication capability.  I easily could have pressed the Milliput master into four or five small blocks of clay today, and mixed up enough resin to fill all the impressions simultaneously.  A fleet in 10 minutes (well, not counting cleaning up the edges and detailing the back).  Hopefully the cast will take paint well enough to bring out the details; I really like the fast duplication possibilities of this method.

14 September 2012

Milliput Scratchbuild Spaceship

I finally went out and bought some Milliput Superfine to use in my first attempt at spaceship scatchbuilding with two part epoxy putty. 

I've dabbled in figure sculpting before using Kneadatite (more famous as "Greenstuff") and ProCreate.  I found both extremely difficult to use.  I tried and liked regular Milliput, especially the fact that it smooths with water; the only problem is the graininess of the cured product.  Milliput Superfine is advertised as having the same water-smoothing properties with none of the graininess, at an increased price of course.  It's worth the extra money.

For machine-like parts I love this stuff.  Just smash the proper amount of putty on a prepared shape (laminated plastic strips work well), smooth with water, then make panel lines.  Easy.

I kept this first design simple and rough on the edges since I was just experimenting with putty properties.  Now that I've got a handle on it, I'll try a few more complex designs and clean them up properly.  You can see where I sculpted the front half, stopped, then started again later with better tools and different techniques.  I prefer the look of the back half of the ship.

45mm long; will cast in resin

09 September 2012

Scratchbuild Spaceships and Weird Resin Reactions

I had a four days off last weekend and decided to sculpt up a new spaceship.  I made two halves like I normally do out of water-putty and used Alumilite HS III to make molds of each half.  I tested out my jury-rigged agitator device to prevent bubbles in the water-putty masters, but honestly it didn't work any better than just tapping the air out.  I know it would work better if I attached the motor directly to the suspended platform and if I used less rigid springs.  Oh well; that's science.  I would try to improve the design, but honestly I'd rather use my spare time for scratchbuilding miniatures.

Anyways today I poured resin casts of each ship half and combined them.  A weird thing happened.  The top hull which I poured first cured perfectly with a normal off white color and no bubbles.  The bottom half I poured second and while it cured I set the top hull against it so the two halves would fuse together to form a complete ship.  I knew the edges would be a bit rough, but for some reason the bottom hull never changed from the dark brown color of the uncured resin.  The plastic solidified fine, it just didn't change color.  If anyone out there has more experience with resin and can explain why, I'd appreciate it.  I'm guessing maybe insufficient mixing?  Or perhaps the recently cured resin of the top hull touching the curing bottom hull caused a strange reaction?  I don't know, but I know once primed it won't matter.  I've still got a lot of work to do with file and blade but once I get the exhaust nozzle on the back of the ship and antennae cluster on the front, I think it'll look OK.  I am however going to give up trying to mash ship halves together like this.  The join line just looks too sloppy.  From now on my ships will be either simple one part mold casts with flat bottoms, or complete three dimensional sculpts with a proper two-part mold.
Bottom hull mold

Top hull mold
Top (cured normally)

Bottom (abnormal cure)

In addition to this ship, I also started on a new sculpt and am about 40% complete.  For this sculpt I'm experimenting with a totally new technique and finally taking a few timid steps into the world of two-part epoxy putties.  I'm using Milliput Superfine and so far I love its properties.  As you can see, I'm keeping the design very simple.
Deep panel lines to catch ink washes

Finally, here's a shot of some micro-armor I started way back in June.  The turret and hull have been completed since then but I'm working on the tracks slowly.  I hope to mold all the parts and have a platoon of four tanks done soon.