Bought a WorkBee 1510 late last year and have successfully used it on some smaller items. However, now that I'm trying to cut some larger parts, I'm starting to see the x-axis lose steps, in particular when transitioning from positive y-direction cutting to positive x-direction cutting (along a 1/4 circle transition of around 1" radius - tho I've seen similar behaviour on larger radii transitions too). I've tried the following things: - Set feed rate to 1000mm/min - Set step-down to 1/2 tool diameter (so 1/8" for each pass) to reduce load on steppers - Adjusted x-axis current down slightly (on theory that x-axis driver was overheating by holding x motionless during long y-axis cuts) - Adjusted x-axis current up slightly (on theory that it was not getting enough power and stalling/skipping when under load when cutting material) - I'm using a Makita RT0701C trim router with shim to hold steady in Z-Axis hold. Makita is running at relatively low RPMs as otherwise I burn out my 1/4" HSS dual-fluted spiral end mill. When cutting with a 1/8" end mill I don't see this issue. - Am using the xPro controller board (V3 I think) - I'm cutting pretty standard 3/4" G1S plywood. Any help or suggestions would be much appreciated!
Check your pulley set screws. They may have come loose. The easiest why I've found is to power up your motors (so they hold position). Loosen one side of the belt and try to pull the belt (while still engaged with the pulley) through the other side. If it moves, then you know your pulley is slipping.
I did have an earlier issue with my x-axis pulley set screws coming a bit loose, which resulted in some play in the x-axis and less accurate cutting. When that happened, I replaced one of the set screws with a small regular screw (same threading) and tightened it up securely to avoid this problem. I checked them again as you suggested to see if there's any slippage - and it still is securely attached. BTW when I tested the pulley the first time I had that issue, I powered up the motors, and made sure I couldn't move the z-axis assembly along the x-axis easily. This is how I diagnosed the play in the first place. I also checked that my x-axis belt is good and tight.
Did you ever calibrate your machine? I'm asking because you say that you're noticing it now that you're cutting larger parts.
I did calibrate the wheels (i.e. adjusting eccentrics) per construction video - but I'll go back and re-check. Could it be possible that the x-axis belt tension is too high? Is this what you mean by calibrate?
Sorry, no. I should have been more clear. I mean calibrating your steps. Check out the video below. Or if you are running the OB Control software, you can calibrate within the grbl settings tab. Super easy and the way I suggest.
Thx for the link! Definitely hadn't done that calibration. Have now checked both x and y axes. Changed from 26.6 steps/mm to 26.7 steps/mm for both and now pretty accurate. Would that small mis-calibration have created an issue with missing x-axis steps tho? I would have thought it would have just made my part ever so slightly undersized...
A few questions... Which steppers are you running, the regular or the high torque ones? Have you noted any binding in the wheels? Do you have a cooling fan on the xPro?
It's more a case of what would it feel like. Noticeable resistance or tight spots when you move the axis across by hand. Beyond that I really can't offer much. I don't have experience with xPro boards. You might go over the current adjustment one more time to see if the issue is there. Also recheck the wiring for loose connections (something that is a source of similar problems far more than most people realize). You might also look into the possibility of EMI interference. Try a run with the router turned off and a pen mounted in the router chuck to see if it follows the same path. If you've got grounding make sure it is single ended.
Thanks for your advice! All axes move smoothly when I move them by hand - so don't think binding is the issue. I will check the wiring connections and current adjustments again. I did notice this issue when running without the router turned on - at the time I thought it was related to running at too high a feed rate, but I'm now seeing it at lower feed rates. BTW when comparing the xPro board vs the new BlackBox Motion Control System, it looks like the BlackBox has substantially more heatsink area.
Not only more heat sink area but also drivers that run smoother and can provide up to the full amount of current that the steppers are rated for.
Apologies for taking a while to close this out - in the end I purchased the BlackBox Motion Control System which appears to have resolved all my missed step issues. Very happy with the BlackBox performance as well as it's lower profile mounting on the Workbee!
