Limit Switches Stopped Working

I've been printing for awhile with no problems, but recently the limit switches stopped working (Y mainly and X sometimes). I checked all the connections and they were all fine so I think it may be a mechanical issue. I noticed the bed has to hit the limit switch at a high enough speed to press it in. I got it working eventually by just tightening the belt and applying wd40 to the steel rods, but I'm sort of wary of it happening again. The switch itself seems normal when I test it with my hand, the bearing trap is making solid contact with it, and the belt clamps are all tight. My y belt did have slightly lower tension, but I'm not sure how that'd cause this to happen. Any ideas what's going on?

And if it does happen again, is there any kind of fail safe to stop the motors when enough skipped steps are detected? I've been at the printer everytime it's happened so far, but I'm worried it'll finish a print, home, and then happen again when I'm not. Thanks for any help.

The Y limit switch should trigger 1mm before the end of the axis but due to a buildup of hole clearances that can become zero. To fix it loosen the front left bar clamp and slide it as far forward as you can and loosen the corresponding bearing holder and slide it backwards.

X should be fine as long as you tighten the extruder bolts so they go at least all the way through the bearing block and make sure right hand wingnut is not protruding.

I can't see why you need to home at the end of a build. The machine knows where it is at so you can just G1 to where you want it to be.

I don't think Marlin steps forever if it fails to find the limit switch. I think it goes for something like 1.5 times the axis length.

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[www.hydraraptor.blogspot.com]

That seems to have worked, hasn't happened since, thanks. Just out of curiosity, is skipping steps for 1.5 times the Y axis enough to permanently damage the motor?

Stepper motors aren't damaged by missing steps.

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[www.hydraraptor.blogspot.com]