Afternoon All I have been trying to calibrate my Oooznest workbee screw drive. Seems I am chasing my tail,each adjustment I make throws the cut out in the other direction. My calculation are show along with my measurements. Has anyone experienced this? Link to the block I am cutting Fusion Also G-code for 8mm Flat EndMill Regards Colin
Hi @Colin Hart , I don't follow your spreadsheet. In cut 1 did you have steps/mm at 400 and get the result shown? Then in cut 2 did you have steps/mm at 410.25 for X and get 105.9 instead of 100? In your spreadsheet you have the steps/mm column at a constant 400 rather than the new values from the row above, so I'm not sure exactly what you did? Alex.
Het @Alex Chambers cut one is the first calibration cut. the measured dimensions are after the 1st cut using 400 steps per mm. So the cut should have been 100mm on the X, I measured 97.5mm on cut1...
Checked that shaft couplers arent slipping on the motor shaft/leadscrews? Hold endmill (router off of course) and give it a wiggle, see if theres any undue movement (backlash) and follow tactile clues toward the source
I think I read the chart as all the cuts are made with the steps/mm set at 400. if this is correct and you are getting different measurements, then a calibration problem is not what you need to be chasing.
Hi @Colin Hart , when I calibrate my machine I use the pointiest tool I have. I don't actually cut - I have the tool about 1mm above the spoilboard and measure how far it travels - I usually use a distance of 400 mm. That way I know I'm only measuring the accuracy of the drive chain. If you measure an actual cut you are (as is suggested above) introducing other variables. Alex.
After doing what Peter said, I would focus on one axis at a time. Use a v-bit and a ruler and try sending it 500 mm. Then do the steps/mm calculation. Once that is dialed in, repeat on the second axis. This will remove any error you are getting in the cut from inaccuracies in bit diameter. I posted a video here using a v-bit and ruler along with the formula for doing the math. Ace Skwal Machine - Setup and Questions
Evening All from my garage... Ok... I'm feeling rather ... dumb!!! two errors 1. in the new ooznest web interface there is a customconfig file, I have the calibration specified in there, this is fine except if it is in the config file, the config file take priority... 2. I was indeed chasing my tail... after each calibration run I left the step per mm at 400, rather than updating it to the value of the last calibration entry... Good news its working now...... Thank you all so much
