Building a mini i3 LC

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The first Prusa i3 I built used a 6mm-thick acrylic frame. It worked ok, but when I saw sgraber's design I thought it will add a lot of rigidity to the acrylic frame. I later bought an aluminium frame and I forgot about the matter.

Recently I came across a local business laser cutting acrylic and I decided to give it a go with a similar but smaller design. One of the things I have observed about 3D printers is that they tend to be big. Having a large surface for the print area is nice because you can print big parts, but you pay the price of the printer being bulky.

As many of the things I print at home are small parts, I thought I would be a good idea to have a small printer at home and keep the larger ones for larger printers I might have at my office. Of course it is still to be seen whether things will work out this way or not.

So I ended up building this smaller sibling of my home Prusa i3.

These are the sizes of the rods I have used: 
  • X-axis: 2x265mm smooth rods
  • Y-axis: 2x270mm smooth rods, 2x290mm M8 rods, 3x130mm M8 rods, 1x210mm M8 rod.
  • Z-axis: 2x255mm smooth rods, 2x195mm M5 rods.
All smooth rods are 8mm diameter. 

I designed a bushing holder for this carriage to needs to be above the rods a bit more than usual.


With the compact extruder in the picture I get 100x120mm of print-head travel. I might change the extruder for a more compact one to get 120x120mm.

The frame seems rock-solid.

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