please help me blv setting
-
can you show us a video of the printer in action?
Maybe share a sliced gcode file so we can see the slicer settings?
-
@phaedrux yes OK thanks
-
@sgk that z wobble design is notoriously bad for allowing planar shift of the bed as it rises. It’s not appropriate for a kinematic connection on two z axis system. That is likely a significant source of the banding, as you’re exacerbating screw matching variance and rod straightness. You’re better off with a pinned connection on at least one end.
-
interesting observation, @Nuramori!
-
thank you very much for your help.
Can you explain to me because I do not understand very well what you explained. -
@sgk the magnetic coupler (similar to an oldham coupler) if installed on both leadscrews allows for a loosely coupled mounting of the leadscrew to the nut. If both z axes are loosely coupled, the plate can wander around because both sides can move. to avoid this, one side needs to be fixed.
-
@oliof said in please help me blv setting:
The magnetic coupler (similar to an oldham coupler) if installed on both leadscrews allows for a loosely coupled mounting of the leadscrew to the nut. If both z axes are loosely coupled, the plate can wander around because both sides can move. to avoid this, one side needs to be fixed.
Looking at the earlier posts & photos, the Z axis is on linear rails and only the leadscrew nuts are decoupled?
-
@rjenkinsgb I trust Nuramori who knows the design of this machine if he says this can cause planar shift.
-
@oliof , yeah, that part of the machine I'm pretty intimate with :p.
I didn't like anything that was out there (initially when I started building it, there wasn't even a three z-axis design), so I designed mine from scratch, and utilized a Kelvin based kinematic system. Later, I upgraded it with a "z-wobble" interface to take care of that last bit of possible influence from less than perfect rods that weren't concentric about it's axis. It can move vertically, but the connection is decoupled from the rod movement in the x and y direction, as the vertical movement is defined by the MGN rails.
I chose the Kelvin approach over a maxwell design because ONE of the points is completely fixed in all axis, and maintains a predictable direction of thermal shift for the bed, and in general, pins the bed to prevent possible random movement when moving along the Z axis.
-
@nuramori Hello and thank you for your answer, it's possible to explain to me how you did it because if I understood correctly you have 3 axes, is that right?
And you have to talk about kelvin find you where this information please it is possible if you could help me to do the same as you to see if I get a good quality I am ready to do anything to find a solution to my problem.
Thank you to all of you for your help.
