Wide 3D Printers?

If resolution of print is not high priority, what do you think is practical limit for extrusion head?  I'm sure you'd need a very large heat block, but you could design a hot end that has a 1-2 mm diameter or maybe even bigger. If you were to print at 1mm layer height you could have a 5x increase in speed compared to 0.2 layer height.  Maybe you could even feed multiple filaments into head for even larger extrusion.   If you were designing a fender for a car (1:1 print), I think 1mm resolution (z axis) would get you pretty close.

BK

Most of my projects would be of the prototype variety with the rare exception of some "unique" fixes or adapters.

One thing that would help would be an accurate scale 3D model of my car. I've worked in full scale for so long I keep forgetting that I could "scale" down.

I guess I need to watch more of your shows to see how to print multiple pieces and assemble them together to make a larger product.

This stuff is just too addictive!

Another thing to keep in mind is bed leveling. The larger the bed, the harder it is to keep it all level.

So what you gain in size you might lose in accuracy / having to redeo parts.

Also a wider X gantry can be prone to sagging.

Students at the University of Washington built a RepRap cartesian-based design to melt milk jugs and extrude them to make a boat the students could paddle in a yearly race. that was well over the size you are talking about, while Contour Creation's cement printer is room-sized. Rigidity is the buggest problem, with bed level control and material feed to the extruder being close behind. A fully-articulated arm like the Materialize system uses could handle any volume within the extent of its reach, so long as it was firmly attached and capable of measuring the bed's level before starting a print run. For a scale-up of a regular RepRap, you could go with one of the extruded aluminum designs that tend to flex less than rod-based designs. For the "3D Printing for Dummies" book I am writing with RichRap, we are using extruded 80/20-based kits (MendelMax from Maker's Tool Works for the Cartesian design, RostockMax from SeeMeCNC for the Delta design, still looking at Polar designs right now - no kits available for those just yet). However, it is entirely possible to make a 3D printer out of hardwood, roller skate wheels and stepper motors from surplus printers, so don't let anything stop you - just build one and start printing the parts fo the next one!

VR,

Kalani Kirk Hausman