STLCutter 2 - Preliminary work

While uploading a YouTube video of the original STLCutter, I found a number of other DIY CNC milling machines there - and found one that I liked. So, I used its ideas for my design.

The design goals were:

• The foam blocks we'll be cutting are 1200x600x100mm in size, so the machine was designed to have a maximum cutting area of 1500x1500 to allow two blocks to be placed on the machine at the same time.
• It would have a low centre of gravity, and made out of heavier steel than the original cutter. This should prevent the wobble.
• It would use proper CNC parts, rather than things I thought would be suitable. The first version was a proof-of-concept in reality, and only a small amount of money was spent on it. Using proper parts would give it speed and accurracy. The aim is 15+m/s, but anything above 5 would be nice.
• It would use a router rather than a dremel - this allows much more "exotic" cutting heads to be used, as well as give us the option for cutting wood and aluminium (possibly steel with the right bits).

The design looked like this:

I was planning to use an existing Z-axis mount for the router (this wasn't actually done due to a number of reasons).

There would be enough space for a slighly taller foam block:

The bottom board (made out of MDF) would be supported by a cross-frame, and also supports at the end.

The over-long X-axis would give extra stability for the Y-axis frame.

Oh, and the design on which it's based is this one.