Inconsistent cut depth

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martin54
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Re: Inconsistent cut depth

Post by martin54 »

Does the machine home when you first start mach3 & does it home all 3 axis or just the X & Y as mine does? Keep meaning to fit a limit switch to the z axis for homing but still haven't got round to it. Can't really see why turning mach3 off & on again would make any difference unless it some how ended up positioned differently.
I've only recalculated all tool paths a few times but haven't ever had any problems when I have.

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zeeway
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Re: Inconsistent cut depth

Post by zeeway »

In my experience, Z height problems can come from a slipping coupling; or feed screw/ways not well lubricated so it is sticking and then slipping; on a feed screw, a bad feed nut; a spindle that is too heavy for the motor; or lost steps. In my case, I tried everything but replacing the z motor...finally decided it was lost steps...apparently the parallel port on my computer was not putting out a consistent 5v signal...so I installed a SmoothStepper output board and made sure everything was well grounded.

This CNC stuff can drive you crazy, but when it works....life is good.

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dhellew2
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Re: Inconsistent cut depth

Post by dhellew2 »

I've had a similar problem a few times, turned out that the upper z-axis thrust bushing mount had worked loose. The router was lifting up during the cutting process. Dale
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Leo
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Re: Inconsistent cut depth

Post by Leo »

MF2014 wrote:Hi all, just wanted to give a quick update. I talked to the manufacturer and they gave me a few things to check, mostly related to the Z axis gearing and any obstructions that might cause it to shift. I also have a few things to check around making the table a bit more solid (to prevent any movement when its running). I don't think any of this is the actual cause, reason being if they were, the changes in height would be more "inconsistent". The way it is, when it changes height, it stays that way for a full pass or 2 or 3, then changes again. If it was anything like shake, obstruction, etc, I would think I would see variations in a single pass. Also it was suggested by the MFG to make sure all of the connections are tight, I plan on spending time this weekend doing a full check of everything and give it another test run.
Was this resolved?

What was the final fix?
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