kinematics of bed plate adjustment March 14, 2016 10:15AM |
Registered: 9 years ago Posts: 33 |
Re: kinematics of bed plate adjustment March 14, 2016 09:01PM |
Registered: 11 years ago Posts: 5,780 |
Anonymous User
Re: kinematics of bed plate adjustment March 15, 2016 06:47AM |
Re: kinematics of bed plate adjustment March 15, 2016 09:10AM |
Registered: 9 years ago Posts: 33 |
Re: kinematics of bed plate adjustment March 15, 2016 12:39PM |
Registered: 11 years ago Posts: 5,780 |
Anonymous User
Re: kinematics of bed plate adjustment March 15, 2016 03:49PM |
Quote
rmlrn
Thanks guys for the comments but I'm a bit confused, my drawing has 3 adjustment points not 4, in total agreement with you about that!
My bed is 3/8" cast jig plate and only 200x200mm, so I'm pretty sure it rigid enough to stay flat only supported at 3 corners.
I'm more concerned about potential warping forces due to overconstraining the system, even with 3 just screws.
A ball in a circular cavity at one corner provides a fixed point contact, and a ball in a slot at another corner provides a line contact which fixes rotation around that point.
At this stage, the assembly is fulled constrained - really the adjustment at the 3rd corner should be free to float in both dimensions, but I can't figure out how to do that while still having the spring pushing the bed away from the support.
This diagram is probably clearer than my sketch: