Cute design! Can I get this in an R2D2 case?

Cute design!

Can I get this in an R2D2 case? :wink:
http://www.buildlog.net/blog/2013/04/the-quantum-delta-3d-printer/

Yeah, also means that it’s really hard to keep prints from getting knocked over and it has an atrocious ratio of build volume to machine volume.

The main benefit is for those subset of cases where the extruder is (and needs to be) significantly more massive than anything being printed. Such was the case in the old MakerBot Cupcake days. It doesn’t make sense for plastic extrusion any more, but could for exotics like Moineau pump based chocolate extrusion.

*Significantly more massive than the print and the platform. A good platform with heater and heat spreader is likely to have comparable mass to the extruder, unless (as in this case) it is a very small platform.

Don’t all delta printers have a “atrocious ratio of build volume to machine volume”?

Not necessarily. The radius (compare to X and Y on cartesian systems), you should be able to do better than 2:1 (with a theoretical limit approaching 1:1), whereas this version will be lucky to get 3:1 (with a theoretical limit approaching 2:1). For comparison, the theoretical limits for X and Y on a cartesian system are 1:1 on a axis where the extruder moves, and 2:1 on an axis where the platform moves, though a typical machine usually achieves roughly 2:1 in either case.

For most cartesian designs that are appropriate for 3d printers (including deltas), but usually not appropriate for mills, the ratio for the Z axis gets better as the build height increases because the machine height scales linearly with build height. Again, with the exception of exceptionally tall machines, a 2:1 ratio is pretty standard. In the case of deltas, the length of the arms (a function of the machine’s radius) is one of the limiting factors for the machine height/build height ratio, so a space-efficient delta must be very tall and narrow (though, of course the irreducible portion of the width will be a larger proportion if the machine’s radius is very small). This machine appears to have a build height not much greater than its build radius. I would estimate about 6:1 from the picture (considering the domed shape of the upper limit of a delta’s usable build area).