I make props as ArmouredBrownies , and I use a mixture of tools and techniques to do so.
Recently I've been using 3D printers to help me make objects more accurately, and to a higher degree of quality. But 3D printers have an upper limit on just how nice they can be. I would never consider a freshly printed object to be a finished prop, ready for use in any costume. Unless of course that's the effect you're going for.
I have used 3D printed props as a base for a few costume pieces and here I'm going to show you how I used both a 3D printer and a Silhouette Portrait Vinyl cutter to create a highly detailed replica prop item.
In this tutorial I'm going to show you how I solved a problem of adding a high degree of detail to a mechanically accurate costume piece for my Thor, Goddess of Thunder costume. This is a costume I'm intending on putting a high level of detail beyond the original source, but basing it on common design elements from the movie version of Thor.
In the movie, Thor has a design embossed on the 'Pucks' on his armour, the little round plates. They're too fiddly for a 3D printer to replicate well, and would need replicated many times over so impractical for a sculpt, so, we're going to use a 3D printer, some body filler and a Vinyl Cutter to create the same effect.
Step 1: 1) 3D Model and Print the Originals
First off, design your original.
I use 123D Design, as it's free, very straight forward once you have your head around it and outputs to Slicer readable STL 3D model files nicely.
You can find a copy of the file I worked off here, at my ThingieVerse account:
Once you slice it up to the settings of your 3D printer, just, well, erm, print it!
You may need to play with settings and scales of the final piece.
Step 2: 2) Smoothing and Priming the 3D Print for Moulding
Now for the boring, dull and annoying part; turning the 3D printed object into something that you're happy to work on.
What you get out of a 3D printer is never ideal, there is lots of texture you want to get rid off. I use a mixture of sanding, filling and building up, and then rinse repeat.
The material you want to use is a polyester body filler such as Isopon P38, any generic 'Easy Sand' filler or Bondo for our American friends. Once you've filled in the striations of the printed part, you then sand it down, repeat a few times, and then you start using a filler/primer spray, that fills in the even finer imperfections of the piece.
This took me an evening to do it with the pucks of all three sizes so, don't be afraid to take a while over this, it's something you only have to do once. Anything you don't do here will be repeated in in every casting you make and so will create more work for yourself.
Step 3: 2.5) Additional Setp 2, Moulding the Blanks.
I made a silicone mould of the PLAIN pucks, rather than running straight at the finished embossed pieces. This is why from this point onwards you see that I'm using resin cast plain parts rather than the nicely smooth and sanded pieces.
I did this so I could experiment with the black pucks without worrying, so I could change the design on the pucks if I needed to and just to give me more options, but if you are short on silicone or time, you can skip it and go straight to the embossed version.
Step 4: 3) Embossing With Vinyl Cutting
Now here's the interesting part!
First we take our design, that is mine. Designed in Inkscape, a free piece of software that is very powerful for this.
The good thing about it is that you can scale it out as you work in a 1:1 scale in the program. Despite having the original 3D model files, which are themselves a full scale digital object, I used a digital caliper to measure the resin cast versions just to make sure I know what I was working on.
To get a thick enough material to have a visible layer I used sheets of standard acetate, but as it turns out self adhesive vinyl is just about thick enough to give a really nice impression as well and is a HELL of a lot easier to place on the object as it's flexible, can stretch around uneven surfaces and, clues in the name, is self adhesive.
For this I used standard mounting spray on the back of the acetate to stick it on.
Because the acetate doesn't stretch or compress, where it wanted to fold over itself I had to cut it and layer it over itself, this was done easily with a sharp knife and wasn't visible in the final project.
Then just like before, I used a few layers of spray paint and sanding to blend it all together, this is MUCH less needed when you vinyl instead of acetate, I learnt that as well from other experiments.
Step 5: 4) Silicone Mould Making
Welcome to the fun part.
This is a standard dump mould, made using surprisingly cheap silicone and waste corrugated cardboard and hot glue.
The best thing about this type of mould is that you can be very accurate with the amount of silicone you use, as it's a very easy calculation of to how much silicone you'll need if you measure it out by volume, just use a ruler and measure the dimensions of your mould, times them all together and then make sure to add the catalyst by weight afterwards.
You can see how clean that mould comes out afterwards, it's nice and simple.
Then you can use that new embossed version of the mould to resin cast the shiny highly detailed resin cast pieces!
As always, the first casting will be mostly there to clean the mould out. But they're good to experiment on and these pucks don't take much resin.
Step 6: 5) Paint and Finish Your Prop!
Now, you do what you want with the finish prop!
There are loads of painting tutorials in the world go find and follow one with the desired style. If you want me to show you, just drop me a message and I'll write another thing. You can see from the photos I've tried a few different ways to paint them up, involving weathering, spray cans, miniatures paints.
I'm still a long way off having a costume to mount these on, as they're the first parts of my costume so far.
Thanks to SoMakeIt for the use of the Vinyl Cutter, would not have been possible without it.