Here are some of the settings needed in order to run the stock OF unit [hardware] with a GRBL based controller: [GRBL Configuration Reference]
Settings $100-$105 are needed to ensure accurate movement (distance)
Formula: steps_per_mm = (steps_per_revolution*microsteps)/mm_per_rev
steps_per_revolution = 360 / 1.8 (degrees per step for stock motors) = 200
microsteps = The microsteps per step of your controller (typically 1, 2, 4, 8, or 16). Tip: Using high microstep values (e.g., 16) can reduce your stepper motor torque, so use the lowest that gives you the desired axis resolution and comfortable running properties. (for my controller it’s [8])
$100=160.000 (X Axis)
$101=160.000 (Y Axis)
$102=400.000 (Z Axis)
$103=160.000 (A/Y2 Axis)
$104=160.000 (B Axis - not used, but I set it as default)
$105=160.000 (C Axis - not used, but I set it as default)
All my current settings (work in progress as I tweak, especially acceleration):
First of all does this show you get 160 steps per mm on x/y and 400 on z?
Would I need to changes settings somewhere to get these values? Where are these settings located?
What I’m trying to figure out (without actually testing it) is what is the minimum mesh resolution I can use to calculate tool paths before I’ll notice a difference.
Say I’m calculating tool paths from a mesh,(not a solid nurbs object), and each poly face is .25mm and I’m using a 1/16" bit (4.064mm). I assume my final cut wont capture all the detail from the high res mesh because the bit is not fine enough.
If you have 160 steps per mm how could you ever capture that detail in a cut? Am I misunderstanding this?
Is it safe to say that a mesh with poly faces smaller than half cutting diameter wont be captured in the final cut?
These settings are specifically for those who are NOT using the Onefinity/Buildbotics controller. (aka - those setting up a new controller - specifically one that’s GRBL based). If you’re using the default Onefinity controller, none of this applies to you, and it can be ignored 100%.
To your questions about calculating steps, you’re missing one other very important thing - micro-steps. This setting does not indicate a minimum the machine (motor) is capable of, it’s simply a base setting for the controller to understand the dimensions of the hardware setup (as indicated in the calculation, dependent on the driver, lead screw, and motor). The controller can then create micro-steps, which will create additional detail if needed to adhere to the path identified. Of course there’s a limit to this at some point.
@wolfkabal , Would you mind sharing which control software you are using as well as the controller itself. Curiosity mostly. I would assume these settings should work for any grbl control. I am setting up the Openbuilds Blackbox X-32 on mine.
@memphismachinist - Sadly I left this project far in the past, specifically because I couldn’t find any good control software that fit my needs. I was using CNCjs to get started, but it simply didn’t live up to my needs. As for the hardware, I started off with the CNC xPro v5 - it currently resides in a drawer of other failed projects.
I already had experience and hands-on with the Acorn controller from Centroid and a Gecko G540 driver board. I used that for a little bit and it worked well as the endstops/homing modifications I made worked well there.
Since them, and before it was officially released as the I did a self conversion to the Masso controller to make it an unofficial “Elite”.
So sorry I can’t provide more details beyond what I started above, but it didn’t’ make it far past that.