El Beast - Initial design phase, comments and critique welcomed!

[Zeeflyboy]

I'm using my trusty old makergear m2... I've had it for about 5 years now and it's still churning out lovely prints. I actually designed myself a new super duper printer which I'll make one day once this CNC machine is done, but that's really just because I want a bigger beast with quad extrusion and dual independent heads. Oddly enough makergear just announced their new version that does have dual independent print heads, but I would still want the larger build platform to make best use of them (I love the idea that you can print two sets of the same items simultaneously, effectively doubling output of parts if you need more than one of anything).

Material is some stuff called Cheetah by ninjatek. It's a flexible rubbery material a bit like hard skateboard wheels, 95A on the durometer scale... fairly easy to print with if you have a direct extrusion head. I believe it even works with some bowden printers.

Workholding wise for these big pieces I have been using a 12mm sacrificial sheet of SRBP, skim it level and then where the parts have suitable holes I run a "jig drill" drill cycle through into the bed that then allows the hole to be tapped and a screw inserted without moving the part. For the exterior clamps I either try to find a previous hole that works or just drill a new hole and tap. I keep going until either I skim down too far or it becomes like swiss cheese and then I replace with another sheet.

It's not the cheapest option I'm sure (a sheet that size costs around 30 quid) but it's a wonderful material for stability, machinability, coolant resistance and accepting threads/dowels etc.