Hi,
I’m building a 1x1.5m ooznest Ox with a controller built around patching an Arduino Duo running TinyG2 to a RAMPS 1.4 driver board (Currently A4988, with planned upgrade to Ti DRV8825’s ) and 400w Brushless Spindle.
I am currently running in whole step mode, due to incomplete wiring and my impatience to start cutting things. 
I have managed to successfully cut a diamond calibration and a custom part from MDF with a 6mm end mill. The gantry seems to visibly step but curves and circles are as expected (actually better than I expected TBH)
Last night I tried to cut some 3mm MDF with a 2mm bit (w/ 6mm shank) and it plunged straight into a full depth 7mm cut (I think I had miss-zero’d the Z axis). There was a LOT of vibration / chattering, more than with the 6mm end mill, and it shook the material out of the spring clamps I was using multiple times. Running max RPM on spindle ~10kRPM?
My questions:
How do people secure there spoil boards to the OX frame? if at all?
Is there a way to check spindle and collet run-out without a dial indicator? I’m using a cheap er11 collet and I’m a bit suspect.
Is there a standard set of TinyG or TinyG2 settings? I’ve looked hard and can’t find much, and the default settings where rubbish. (I have x/yvm and x/yjm set ok now I think) I can past my config file latter.
Thanks,
Jeremy
Hi Jer
I have 8825’s in the mail you can have when they arrive. I found another driver solution while they were still being sent.
You should really go to 1/4 or 1/8 stepping. Much smoother.
You should really use a probe. Lots on YouTube for it.
I don’t know what you’re feed was but 10k with a 0.4kw isn’t much power, you may have to take it light.
I used cast corners, one bolt into the frame and a screw into the spoiler. One on each corner.
you need a dial. Only thing is to peck a hole and see how much bigger then the bit it is but that’s never just run out issue.
Thanks, I actually have a full set of 8825’s on hand, but I figure if I’m going to cook a driver due to dud wiring, I’d rather it be a A4988. (I even had a faulty A4988 !! Step pin always pulls high.) I figure 1/8 is going to be heaps better, but I’m still surprised at how bad whole stepping seems, even though it cuts ok.
I also have plans to add a probe, it’s on the todo list, right after sorting out the micro stepping.
Full config “$$” dump https://drive.google.com/file/d/0B9akO9fyDbgVc09Yc1NQcUZZT3M/view?usp=sharing
These are the defaults with a few tweaks to get my machine running, I’ve only touched M1,2,3 and XYZ settings. M2 connects to 2x stepper drivers.
I can send you my OX settings as a txt file if that helps. My spoiler board just sits on the OX no bolts. I typically never hit my board so it doesn’t need to be anchored in. Actually mine is a snug fit anyways so that helps with vibrations. Also as Julius said 1/4 or 1/8 steps provides smooth motion.