X axis limit switch question

I’ve moved to Mach 3 and am setting up limit switches for the first time.
I also implemented the x-axis improvement with the single piece large extrusion.
when you do that you need to flip the switch, which I DID NOT DO before I put the x-carriage back on,
meaning that when I unscrewed the little teeny bolts to flip the switch, the even tinier nuts came off the bolts and now I have no realistic way to get them back on without tearing the machine apart, which I am not about to do.

So my question: any tips on ways to attach the x-limit switch to the x-carriage so it will stay on?
Crazy glue? super magnets? what do you recommend?

I used hot glue to attach my switches. I am using hall effect sensors as switches, so both the sensors and magnets are hot glued in place.

Glue might work, but I would think that with a mechanical switch you would get some movement during contact with the moving carriage.

If you still have the nuts, I would tack glue them to something like a popsicle stick and then use that to position them inside the carriage while you put the screw in from outside.

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I could glue it with the bolts still in place: that might hold it sufificiently…?

Don’t know, I haven’t tried it. I don’t see what it would hurt to try it unless you use some kind of permanent glue.

With my switches screwed down I get 0.001 inch repeatability. I guess it depends on what your requirements are.

well yes, that is the requirement, the question is how can I get that again without having to tear the end plate back off of my y-axis.

If the switch will tolerate a larger screw, you could tap threads into the carriage holes and just screw the switch to the carriage.

I used tweezers to hold the nut while screwing in the screw when I did the exact same thing as you did.

When I need to use small fasteners I use a pair of hemostats.

I used a drop of hot glue on the back and then hit it with the heat gun to promote the bond. Worked like a charm. Then used a bit of extra around the switch to hold it better being careful not to get any in the moving parts.

I drilled an m3 hole once and tapped my custom gantry plates with it.
now i would probably just move the switch redrill and tap m2 and then bend the lever arm if needed.

Or mount them on a piece of Nylon which can be bolted with M3 and locknuts to the gantry. The plate extends, in case the switch does not stop the motors in time the plate protects the switch.


By the way, the latest X Carriage drawing shows these holes as tapped now. I don’t know when they rolled that change in there but when I bought mine last year, they were not tapped.

the needlenose pliers did not work for me,
the nut kept slipping to a bad angle.

What I did in the end was use a small amount of scotch tape to fix the nut to a popsicle stick,
and hold it in place that way while I turned the bolt.
Worked quite well, and the popsicle was pretty good too.

Thanks everyone for all your help.
It is really appreciated.

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