So I built my H-BOT last month and have been slowly inproving it week after week:
PROs:
Fast
Perfect circles
No moire
X follower sweet (623 bearings instead of delrim blocks)
Single belt tension, very easy
CONS:
Y gantry 'twists' out of square easily (effects to be seen yet)
Bowden takes some tweeking to get right
Frame is not super stable
There are a few more that have nothing to do with gantry system.
My experience so far is that this system has great potential, at the cost of alot of setup. I have doubled the speed of my SD3 on fine printing (0.1mm). But it takes quite alot of work to get it there. HBOT has the nice part about using a single belt which gets rid of X/Y tensioning circle problems. The bad part is the Y gantry can twist. So far, I cannot tell if it is making any problems or not. I still have alot of tweeking in firmware for acceleration and jerk to see if some of the artifacts I am getting are possibly related to the twisting. a COREXY (crossing belts) would eliminate this twisting, but at the cost of having to tension the two belts perfectly to each other. And I have no idea what the comparison to an ultimaker system would be. My best guess is that it would work much the same as a solidoodle, just faster. The only con I would see is putting it together just right to get the quality.
Chuck Bittner is a quadriplegic gamer who is petitioning the major console developers to include internal button remapping in all console games. You can help.
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