RRF 3 Z home not triggering.
-
@joehsmash My idea was that the Z movemement stuck because you have pressure between left and right side. This was the reason for my proposal. But if you know that this is not the reason, you don't need to make this test of course!
-
@JoergS5 also about that little screw, thats not an issue. its currently not holding any weight other than to just hold the clamp onto the lead nut so that my axis switch stays in place.
as i said before i could cheat it but it would just cause more issues.
-
No problem, don't do anything I propose if you don't want to.
-
-
@JoergS5 i see what you saying.
the way this gantry works is there are these clips that hold the axis end stops in place, that sandwiches the top of the gantry to the lead nut so that when it pushes the nozzle into the bed it will tilt the gantry and raise one of the sides which inturn triggers one of the switches.
on a side note, if the gantry gets too much out of level it puts lots of pressure on the lead screw and the linear rail and as such will not allow the switches to trigger.
right now theres is no pressure between the right and the left screws because i have manually leveled the gantry. only the firmware keeps pushing it out of level.
-
I want to share a last idea what could be wrong: the endstop is very near to the construction above:
Maybe it bumps into the upper part before the switch is activated sometimes.
-
if i take the axis clamps off theres nothing to stop the gantry from just raising until the lead nuts come out of the gantry and it will just sit there and spin forever
-
@JoergS5 right now the NC switch is in an inverted state, the entire weight of the gantry is resting on the lead nut, and the switch clamp is clamped to the leadnut and snugged up to the bottom of the gantry. so that when the nozzle hits the bed, it raises the gantry approx 1mm which causes either of the switches to trigger.
-
@joehsmash said in RRF 3 Z home not triggering.:
if i take the axis clamps off theres nothing to stop the gantry from just raising until the lead nuts come out of the gantry and it will just sit there and spin forever
I didn't mean to remove anything, only to loose one side. (With loose I mean: Do not tighten the screws but loosen them, so that they can give way a little.)
-
@joehsmash said in RRF 3 Z home not triggering.:
@JoergS5 right now the NC switch is in an inverted state, the entire weight of the gantry is resting on the lead nut, and the switch clamp is clamped to the leadnut and snugged up to the bottom of the gantry. so that when the nozzle hits the bed, it raises the gantry approx 1mm which causes either of the switches to trigger.
Ok I understand. That's a good idea and is very precise!
-
Subtle switch trip https://imgur.com/a/RrO48ah
-
I am not sure, but while watching the video, I think I see some subtle rotations of the endstop while it activates. The rotation means Z movement because the endstop is connected to the trapezoid spindel. Maybe this is the reason for your differing values.
-
@joehsmash i dont mean to be a smart a$$ im not,
ive just had this machine apart and back together so many times now that im sure i can build it in my sleep.
i would just like to be able to get back to the auto level like i had before and get back to printing.
-
@JoergS5 i could snug up the lead nut inside the gantry arm for sure. i have some .001 shim here.
-
@joehsmash The video is counting down from 0.25 to 0, at position 0:12 the endstop rotates a bit. This changes the measured value. Because the endstop is assembled on the trapezoid spindle and the rotation itself changes the Z position.
-
@JoergS5 to which i will do in the AM, as i will have to dissasemble the whole gantry and top half of the printer to get them out.
thanks for your help thus far... some times i wish there was just a chat button haha
-
You don't need to disassamble. I think the endstop rotation could be the reason, so hindering it from rotating is a quick test.
Good night! For me, it's morning.
-
@joehsmash said in RRF 3 Z home not triggering.:
some times i wish there was just a chat button haha
There is chat!
-
I will have to take a closer look at this, but I don't think you can do exactly what you want to do using both switches for a single probe type, at least not currently. I'll see if I can find that out for certain.
However, adding an actual probe to the nozzle is by far the best solution. Then you can still use the endstops to level the gantry if you wish, but even so, using the probe makes more sense. The tilt needed to cause the switches to trigger makes for a very compliant system.
The fact that moving 50mm up and back down results in changed position means there is some mechanical slop in there somewhere that must be addressed regardless.
-
@Phaedrux hmm im just not sure where the slop could be. Its only a lead nut and a gantry that is in the system.
And there is a little slop on the x axis where the lead nut goes into the x gantry but to account for over 1mm on 50mm seems like too much.
I have a bltouch that will be here tomorrow.
