Should you recalibrate after hitting limit switches?

X-Carve Troubleshooting
1

How is everyone.
I was doing a carve and I put the wrong measurements in for the “y” on my stock. Needless to say it hit the limit switch a couple of timesand lost loads of steps.

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When I cancelled the carve it went back to work home position and was a mile off.
Will I have to recalibrate the machine before another carve?

2

If the carriage hits an object and its motion is blocked, the machine doesn’t have any way of detecting or knowing that. The X-Carve uses an “open loop” system where it issues motor commands, and then assumes that the motor moved successfully.

So after a collision, the machine’s belief about where the carriage is will no longer map up to reality.

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3

You don’t need to recalibrate your steps. You should go through and inspect your belts for bad spots bolts and such. Your steps are set but you may have damaged something mechanical.

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4

Thanks guys. It wsn’t a crash as such . The limit switch done its job…Gonna go make sure everything is clean and tight now.
Cheers

5

I would run the “Set up machine” again. It wouldn’t hurt. Good luck.

6

Sorry, I just seen your post now.
I just made sure all belts and wheels were in good shape and ran another carve. It ran like a champ and gave a super clean cut so I’m happy so far.

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Thanks for the suggestions tho. I’ll keep it mind if I do anything wrong again.

7

As others said, you lost steps. A simple re-home would correct for the lost steps.

A mechanical check is also good.
Machine setup isn’t necessary.

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9
  • Hitting the switch is just a physical barrier so it keeps going and skips.
  • Yes soft limits would avoid it.
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10

  • At a low velocity, hitting the limit switch will physically stop the motion of the carriage, resulting in lost steps. It’s like a crashed axis, on a smaller scale.

  • At higher velocity, the limit switch will be crushed and destroyed. Even if that doesn’t result in lost steps, the carriage will almost certainly crash right after this and steps will be lost.

  • If hard limits are set in Grbl, hitting a limit switch will stop everything and position will no longer be accurate.

Soft limits should avoid the physical crash, but you would still need to re-home.

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12

No problem man, nice work!

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14

Soft limits are the way to go.

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15

Thanks guys. I’ll have to search out a few guides and set them up the weekend. I have done a few carves since and everything seems fine but I did crash my suck it dust boot into the y rail while homing the machine. Lucky nothing broke.