How to Manually adjust Z-Axis to raise the router bit?

Hi @bar, thanks for taking the time to reply and help with debugging this. :heart:

I have re-done the calibration from scratch several times (removing the sled from the chains and performing the steps to measure the distance between motors (feeding the left chain on the left motor till it reaches the right motor, tightening and measuring) etc. (I have video of myself doing it, if it’s helpful)

These are the current values:
maslow-calibration-values
maslow-calibration-values

After re-attaching the sled to the chains and attempting to complete the calibration, when I attempt to do the test cuts I get the following error:
maslow-not-keeping-up
maslow-not-keeping-up

The sled is not keeping up with its expected position and has halted.
Click the ‘Stop’ button to clear the alarm. More information at
:”
Keeping Up · MaslowCNC/Firmware Wiki · GitHub

I read through the “Keeping Up” trouble shooting guide and noted:

Using a lighter sled or cutting slower can fix this issue.”

So I went out and bought lighter bricks in case the sled being too heavy is the issue … :thinking:

Still no luck. Any further advice much appreciated. :pray:

it needs to be loose enough to move, too loose (like when the latch is open) and
it will wobble around and possibly pop loose and plunge down all the way. But if
it’s too tight, it won’t move and is likely to strip the orange button.

David Lang

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@dlang thanks for confirming. I will loosen it this morning and re-test. :+1:

After loosening the router mount, the Z-Axis motor appears to be moving the router.
I made a quick video showing the “Test Motors/Encoders”: https://youtu.be/3bLxrKhNJmc

After re-attempting the calibration, I (still) get the following error:
maslow-not-keeping-up
maslow-not-keeping-up

The sled is not keeping up with its expected position and has halted.
Click the ‘Stop’ button to clear the alarm. More information at
:”
Keeping Up · MaslowCNC/Firmware Wiki · GitHub

I re-read the “Keeping Up” trouble shooting guide and the only other thing that I could try is substituting the power supply. I am using the default one supplied with the Maslow. It’s connected to a stable power source.

What next? :thought_balloon:

try lowering the feed rate. the firmware thinks the machien can go from stopped
to full speed instantly and because it can’t, too high a feed rate lets too much
error build up.

the other thing you can do is to change the amount of error allowed before the
cannot keep up alert triggers.

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@dlang Lowering the feed rate seems like solid advice when it comes to cutting shapes. :+1: (Thanks)

Right now however, I’m still stuck at the calibration stage and I don’t think I can change the feed rate for the test cuts (at least I haven’t found the setting in Groundcontrol …)

I’m still seeing “The sled is not keeping up …” error. :confused:

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Something else is going on and causing the problem (not feed rate). What’s happening is that as soon as you go to the calibration page for cutting, it errors out with the “sled not keeping up error” even though you didn’t tell it to do any cutting.

I wonder if when you skipped the step at the 0:43 second mark, it through the system into a tizzy. Maybe click “return to center” instead of skip and see if that solves the problem.

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A little more info… when you press ‘define zero’ on the z-axis page, it sends a command (G10 Z0) to tell the controller the z-axis is at 0. Then it sends a G00 Z.25, if in imperial units, or G00 Z5, if in metric. I haven’t seen an error cause by the z-axis not keeping up before and not sure it’s monitored. So, I suspect it’s a sled issue and even though the sled isn’t moving, the check is probably still happening. I think the problem might occur when you ran the test motors/encoders. I suggest resetting the chain lengths and trying again.

Did you mark your chains when you fed them out initially?

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change the max feed rate in the settings, that affects everything, including
calibration

David Lang

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Can you go to Advanced Settings and report what the “Position Error Limit” is set for. It defaults to 2 mm, but could have been corrupted. If it’s set for 0, then it will error every time.

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Hi @dlang (thanks for clarifying, sorry I’m a bit of noob…)

here are the screenshots of our Settings Page in Groundcontrol:


Which one is the max feed rate?
Thanks!

You fell into the same trap that MANY of us have. Click where it says “maslow settings” at the top and select “Advanced Settings” :slight_smile:

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Wow … The “Maslow Settings” looked like the title of the dialog window … (hadn’t thought to click it) :man_facepalming:
Feel like I’ve been shown an epic (yet hiding in plain-sight) easter egg! :egg:

Positional Error Limit” appears to (already) be set to 2. :white_check_mark:

What should I set “Max Feedrate” to? (currently set as 800 … mm?)
Thanks!

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Those are typical values and I wouldn’t expect you need to change them. First try wiping the EEPROM (under actions menu somewhere)… maybe something is corrupted on the firmware. If that doesn’t work, reset the chain lengths (follow the directions in the wiki link I posted).

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And I’m going to be offline for a bit… so I won’t be responding :slight_smile:

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I had to reduce it to ~500 to get the alert to stop popping up.

David Lang

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Where the alarm is popping (based upon review of the video), there is no x or y movement being made, only z axis being raised… and z axis is not monitored as part of the “sled not keeping up” alarm. I think he has “residual” x,y error that is being caught when the zaxis move is being made.

Did anyone ever answer the original question? If the bit is extended how do you get it to retract?

Generally when we don’t hear anything back it means one of the suggestions worked, but there really isn’t any way to know which one it was :stuck_out_tongue:

You can use the buttons to move the z-axis in or out manually, where exactly those buttons are will depend on what software you are using, but generally you want to look for a z-axis button over on the right.

Honestly, I’m not sure. The raise button was physically moving the sled…and then it wasn’t and was raising the bit. The CNC gods smiled on me!

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