@Sphyloid said in IDEX H-Bot:
................. I regard my design as functional given that myself and two senior level engineers, one with a doctorates in mechanical engineering, have reviewed the design. Furthermore I have done extensive FEA on the assembly with a safety factor of 5 for a total deflection of 0.2mm on the Z, and 0.02mm on the X/Y axis.
Given that layer heights tend to be in the order of 0.2 or 0.3mm, then designing a printer which has a predicted deflection equal to that layer height is not a good thing (in my humble opinion). I'm surprised any senior engineers (with or without doctorates) would say that is acceptable.
As for speed, H-bot wins again. When you have enough stiffness, you can use huge motors. To re-iterate, H-bot is easier to engineer when you have enough stiffness. You need to take advantage of that stiffness if you do not want to lose speed.
For FDM printing, the speed is largely governed by how fast you can melt and extrude filament. So while huge motors might allow one to use high accelerations in order to attain high speed, there is little point in doing so if the hot end is incapable of supplying molten filament at the required rate. The best I've been able to do is about 300mm/sec using multiple extruders feeding into a mixing hot end.
Honestly it is quite alarming how little I know about getting this to work at a firmware level. Any tips on where I could get better guidance?
@dc42 has written the firmware so there is little to know. All you have to do is configure it. For info, I'm a 67 year old (retired) mechanical engineer with not much in the way of paper qualifications and I have been able to configure and run a CoreXYUVAB with 6 extruders. So I'm sure that someone who is a clever as you will be just fine. The Duet Wiki contains all the information you need and if you get stuck, this forum is a good resource to use.