Tuesday, February 19, 2019

Use a Scrapbook Machine for Scratchbuilding!

A little while back I picked up a Cricut Maker. The tool is generally used to cut card stock for scrap booking projects but this particular model can be used to cut anything from paper to 2mm thick chipboard. I thought the Mrs and I could get dual use out of it. She could use it for scrap booking and arts/crafts projects in her classroom while I could use it to score polystyrene and cut custom stencils for model builds.

I've made a few stickers and stencils but until now I hadn't used it for making model parts. Today I gave it a go and made the set of landraider doors you see above for a conversion I'm working on.

If you're considering using a Cricut, or any other vinyl cutter, for model building your likely looking for precision and uniformity. With that in mind the first step is to obtain the measurements of what you are planning to build. In my case I wanted to make a substitute for an existing model part. So I went about measuring all dimensions (x,y,z) with a set of digital calipers.

I worked in metric as I find it easier to work with at this scale.

The next step was to transfer my measurements into a graphic which would be accepted by the Cricut. The best, free, tool I have on had for that task is Google Sketchup.

This is a great free drafting program and I've used it for home remodels, furniture, and model design. I drew the doors anticipating multiple layers in order to build the thickness I needed. I am using .5mm polystyrene and need a final thickness of 2mm.

The square in the upper left corner is important for later. That is a 1 inch by 1 inch square for scale. Once the drawing is completed I exported a 2D .PNG file. I like PNG because the transparency works well in the Cricut software. Below is the .PNG file for a set of two landraider doors.
Note: the first picture is for plain polystyrene. The second photo is for a textured polystyrene. In my case I used diamond plate. Please feel free to use this files in your project!
The photo is then loaded into Cricut and inserted into a new project. On the artboard of the new project I make a 1x1 square a quarter of an inch into the board on both the x and y access. I use this to help me adjust the imported graphic to the appropriate scale. It is important that once you have this layout set to your liking that you 'attach' the square that you made to the imported graphic. This ensures that the dimensions and location carry over to the next step.

I've been using the settings below and 4 passes to cut my projects. Your results may differ, perhaps a the knife tool would be better suited for this but I'm using everything as it came out of the box for the moment.

Be careful when loading the tray. Any pieces of material that aren't adhered to the cutting mat have will likely get caught as the machine calibrates.

Once the machine does its work you'll have some beautify scored polystyrene which, after a quick pass of your hobby knife, will pop out nicely. Again, this is where perhaps the heavy duty blade would make better work of the polystyrene, but at this moment I haven't used one yet.

As you can see the work is clean and precise. One could easily design an entire model using sketchup and a Cricut!
Tip: Looking for a good source of cheap polystyrene? Look no further than your local sign maker. I was able to pickup a .5mm 4 foot by 8 foot roll of polystyrene for less than $10!