Z axis misaligning

LowRider CNC Troubleshooting
1

Solved 2 problems today and onto the 3rd. Hopefully this is the last of the issues to solve to get good solid runs.

I’m getting the right hand Z axis motor going higher than the left z axis motor. i checked the cables to insure they were all tight. I have a Rambo 1.3x so there aren’t any voltage adjusts.

On the spring connectors, they both are spanned a little but the acme screw and the motor screw are touching and they are tight.

Suggestions?

Thanks,

A.

2

My gut says go slower. Slower Z rapids and slower z plunges. It could be many things but I way turn the Z rapids down to say 5mm/s, and don’t plunge any faster either. You should be able to rapid Z a bit faster but if there is an issue at 5…there is something serious to look for.

Make sure you have some lube on the lead screws, and give the lead screw nuts a bit of freedom to account for any slight misalignment by not tightening the M3’s down all the way.

3

Added this little tip to the instructions. We learned this on the MPCNC when we switched to the T8’s.

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Just a quick clarification- would you loosen the screw on the T8 or the Motor…

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The brass nut. It doesn’t need much play, say screw it down tight, then back the screws off a quarter turn. If it still binds, go another quarter turn, but I wouldn’t go much farther than that.

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AH! I had to do that on my 3d printer. Don’t know why I didn’t think of that. We need to help Ryan on a Forum area called “Tips to Fine Tune the LR2” - This is a great one.

Thanks Barry. btw- your video was absolutely excellent. TY!

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I add it to the build instructions.

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8

Ok so I’ve aligned a few things differently as follows and still have the left side lower by 2mm consistently than the right.

  1. moved the pipes further out from the table
  2. checked the tension on both the top and bottom side plates on the stainless steel pipe
  3. loosened tension on the M3 nut by 1/4 and 1/2 turns testing in between
  4. Modified my tool settings in Estlcam according to the pix for Z plunge
Although it's better- it's definitely still out consistently at 2mm. I've run the Z axis up manually to 50, dropped it ran it up at least 10 times to monitor the amount of change.

My M3s are a bit stretched out due to the z axis going negative twice by accident on testing a few days back. I’ve ordered in 2 more M3s and they should be in tomorrow late.

However- even with the above, the 2mm is still there.

Is it possible something in the controller or the length of wires going to the opposite right Z motor could be causeing a millisecond delay which isn’t paralleling the acme rods?

 

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Pull the router all the way up so there’s no pointy bit sticking out, and run the z down so it’s resting on the rollers. Measure from the platform to the table, then run it over to the other side and take another measurement. Just want to make sure we’re chasing the same squirrel.

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Well that was a great catch Barry. I didn’t even think about that being a possibility. Yup- the right side is off by 2mm. definitely stunning. I printed the 2 pieces on 2 different 3d printers in this case when the 1st printer had a warp on the bed on the one unit. Never even thought about there being a difference in the 2. THANK YOU!

I’m naming this squirrel Rabid MM.

So- the simple answer to this is print some 2mm spacers for the left side and use that magnificent glue to keep them in place.

 

Thanks again Barry and everyone- This certainly was a weird one for me.

1 Like
11

Woo!

 

I’m fighting squirrels under the hoods of our cars again. Weather is changing and they’re trying to nest in there.

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12

Wow, I would have never guessed that. Dang Barry serious brownie points on that one!

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My z axis is turning in opposite directions. Any suggestions? Im using the wiring kit that came with the hardware

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Simplest way is to invert one of the Z motors connection on the board.

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