I need to re-adjust the endstop screw on Z axis often. Any tips or ideas? Maybe add a nut on each side of the wood piece?
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I need to re-adjust the endstop screw on Z axis often. Any tips or ideas? Maybe add a nut on each side of the wood piece?
Yep! That's the way to do it.
I put a regular nut on the adjuster screw on the upper side of the plate that the endstop goes through. This nut is backed off (moved towards the head of the screw) while the screw is screwed into the plate to get your end position. Then The nut is wound down onto the plate to lock the adjuster screw moving. Since I did this mod, I haven't had to re-set the end stop screw during a print session.
I also put a nyloc nut on the very end of the screw. The nyloc nut touches the switch lever of the end stop switch. Using a nut here just gives more contact area between the screw and the lever.
I found that the best way to adjust the end stop screw position was to connect a multimeter to the terminals of the endstop switch and set the meter to check for continuity. When the Z-axis is away from its Z= 0 position, your should have an open circuit (ie no current passing through the switch) with the meter showing the numeral "1" on its screen. Unwind the adjuster screw out of the plate, then jog your Z-axis to the position you want to have the extruder tip 0.2 mm above the print plate. Now, wind the screw down until the multimeter first shows the numeral "0" on its screen, or it beeps depending on the multimeter, indicating a closed circuit (current passing through the switch). Then, holding the screw in that position, lock it in position by winding down the nut until it tightens on the plate.
Old Man Emu
I thought the endstop switches should be wired as NC, so that if a wire break happens, it triggers the switch. If an NO switch wire breaks, you'll not know it until the axis doesn't stop moving when it should.
you can do this just set your endstops to inverted = true in the fw and reflashQuote:
Originally Posted by AbuMaia
and turn off "endstops only for homing"
i did this and if it fails or has a run away I'm safe
The switch has both NO and NC contacts. The NC contacts are usually recommended for stop switches, but the firmware can be configured for either, and you can connect your meter to either when adjusting.Quote:
Originally Posted by AbuMaia
I'll put in a plug here for auto bed leveling. If you're adjusting all the time, it might be worth it to add a servo-mounted Z probe. Once you get it dialed in, you never have to adjust your Z endstop or level your bed again.
You could be correct. I was writing off the top of my head, without going out to check how things were on the printer. I remember that the two wires on the switch are attached to the posts at each end. Nothing attached to the middle post. When you are looking for the point of action of the switch, you are simply looking for a change in the multimeter reading when the nut on the end of the screw hits the switch lever.Quote:
Originally Posted by AbuMaia
OME
Did a quick fix and replaced the screw, it lasts much longer now before I need to re-adjust.
I'm having the same issue on the 10" i3v.
After every print, I have to either move the micro-stepping screw up or down (if i move it up for a print, I have to move it down for the next print, back up for the next, back down, etc.). I added the nut to the top side of the wooden z endstop mount, and I have a locknut at the bottom of the screw. Still have to adjust after every print.
Short of implenting all the auto bed leveling hardware, what can I do to alleviate this?
While it seems like a lot to do the abl stuff really makes life easier. Its like anything a decent amount of up front time but you save more time than that after the fact.
But as an idea to help you check to see how secure your endstop is to the wooden bracket as well as the screw bracket. It just sounds like a slight shifting or twisting of the endstop. Which shouldnt be happening... But that is a definite potential suspect for the sloghtly changing z position.
I'm glad i read these posts because i think that is exactly what happens with my printer. I'm going to check on this when i get back home.Quote:
Originally Posted by sniffle
Another thought too could be your environment. Are you setting the Z height with the bed and hot end at temp? I had done it cold, printed once or twice, and then the next time the gap between the hotend and bed was visable. Adjusted hot, and it seems better but I am still keeping an eye on it. I have the older 10", so I have to manually adjust the endstop, until I can print out the parts for a micro adjustable setup.
One more possibility - do you have the switch strapped to the wood bracket with zip ties? If so, that could be letting the switch move just a bit, messing up repeatability. I used M2.5x12 screws and nuts instead of the zip ties, using a 3/16-inch drill bit to cut a countersink hole into the wood bracket for the screw head.
i put some thin ca glue on the threads and screw in halfway in and let it dry, then twist it back out a little and set it. this makes it harder to turn but when its set i dont normaly turn it so no big deal.
Been meaning to respond back.
@usarmyaircav: I do home and level the bed when both bed and hot end are at preheat ABS temp.
@printbus: I'm not sure I'm understanding what you're saying, but here's a picture of the set-up:
http://i.imgur.com/kxJUqWv.jpg?1
Thoughts?
My point is that I don't like the Makerfarm approach of using the white plastic zip tie to attach the switch. Unless the zip tie is very snug and tight, the switch might be moving around a bit on the bracket, leading to repeatability issues. On the back side of the switch mounting bracket, the zip ties are also going to keep the bracket from being flush to the aluminum rail - that's less of an issue, but still not a great approach. You end up with a more solid switch mount if the zip tie is replaced with two M2.5 screws, with the heads countersunk into the rear side of the wood bracket.Quote:
Originally Posted by jumi1174