auto leveling

What printer exactly are you using ?

 

Ok I moved your thread from th3 R1 section to the R2 section. To disable autolevel you need to remove the G36 fro. The start up script in both your slicer and octoprint. Replace it with a G28.

This will home the axis and print. Make sure your bed is leveled as best you can.

 

You’d be the first this doesn’t work for and can’t honestly answer the G36 question as I don’t use it. Hopefully someone will come along that can answer for you.

 

I also don't use G36, for reasons I do not want to repeat here. I am not sure what you are asking for works, Homing (G28) only happens at one location on the X/Y/Z planes. Are you saying that if you read the same spot 10 times under the same conditions you have 10 different dimensions for Z?

 

A picture might help us visualize it

There is always the idea of printing it in a different orientation (just a wild stab in the dark since it is not yet clear what you are having troubles with)

 

There are many here that do not use Auto-leveling at all (G29 or G36). once all the points measured on the bed are compensated for the bed plane does not change even with countless removals and replacements of the bed itself. There is simply no need to keep messing with the four leveling screws at the corners.

My own print startup code only includes G28 to home the device. Even though the IR does not read consistently across the entire bed, I don't care because I am not measuring across the entire bed, just in one single spot. If you bed is trammed correctly there is no need to measure anywhere but one location.

To be honest, what you are asking is solved by using MESH leveling of some kind or another (either MESH {deprecated} or UBL) Once the exact plane of the bed is determined and the appropriate points measured and edited, there is no need to ever (actually ever is not the right word, but almost never sounds stupid) remeasure anything but where Home is.

And even though you quoted my post you didn't actually answer my question.

 

While it is soooo 2013 (or earlier) I stand by manual leveling as my approach
If you need that much precision then manual leveling is the only way to go.

MESH is sort-of an automated approach to getting the same corrections as you would with manual leveling so it is really good.

Tolerances on the consumer 3D printer machines is not like a lathe or CNC ... not by a factor of several decimal points.

 

Mark and Waldo here... Geof is not the one responding today Probably off having a weekend

What you are describing is the Z offset it sounds like. The bed leveling screws adjust the physical height, the Z offset wizard and fine tuning wizard deal with the Z offset. If the bed is level then it is repeatable If you are having issues with repeatability then it is not level. You may have a defective switch since even my 3 R1 units (and the newer C2) are repeatable to within fractions of a millimeter for Z offset. When I get it set correctly it will always be the same and so are the layer heights. Those are all using identical $3 limit switches too

 

Bear in mind that when we talk about a level bed we do NOT mean "level" with the world. We mean it is trammed (so that the gap between the extruder nozzle and the bed is the same across the entire surface of the bed).

Same terminology used on the CNC machines and we really should use it for 3D printers, but folks just started using "leveling" to mean "trammed"

 

If you are looking for better than fractional measurements, then 3D printing is not the correct solution for your required outcome. It will never come straight off an FDM technology printer with micron specific tolerances. If that is what you are trying to achieve.

Just a few variables you haven't even mentioned; All plastics expand when heated and shrink when cooled. No matter which one you use, since a 3D printer has to heat to past Tg temperatures (glass transition) and then cool it to ambient temperatures there is always going to be tolerances in the tenths of a millimeter, not hundredths. Then there is tolerances within the linear movement mechanics, not everything is in whole stepper steps and microsteps are undefined mechanically. They are just an electrical division of the required voltage to move one step. You cannot rely on microsteps being accurate to micron tolerances. There is no feedback loop to verify the actual movement you asked for is the movement delivered. Then there is backlash that you cannot control. If you need that kind of accuracy you will need to spend much more than $1500 for a printer, and don't expect any other printer in the consumer space to provide any better tolerances that what I am telling you now. If you want to spend $100K plus then you can get 3D printers that can have tolerance accuracy approaching what you are asking for.

To be honest @mark tomlinson hinted at the real solution, CNC a chunk of plastic to the sizes and shapes you need.