So I have a new Workbee 1510 and I am trying to make a wasteboard. But it's not making round cuts like it was designed in Aspire and even in Openbuilds CAM. Here is a video: Any thoughts? FYI: Utilizing the OpenBuilds Blackbox.
Have you checked for backlash/play in your machine? From the video I would start looking at the pulleys/motor fixing. Are your belts properly tensioned? Alex.
Backlash shows up when you change direction, so surfacing won't show it. Have you measured a square accurately (tip do a profile toolpath rather than a pocket - depth of cut 0.5mm). Also do a profile cut circle about 100 mm diameter, label X and Y axes, measure both axes if you get anything resembling a circle and post a pic. Alex.
I am guessing that the X axis is left - right in your pics. If so you have a problem with your Y axis. The most likely is that the pulley is slipping on the motor shaft and the motor is turning but belts are not moving. It is really difficult to diagnose a problem from 100's of miles away so slow down your feed rates as much as you can and watch very carefully to see if you can spot the problem. If it's not the pulley slipping on the motor shaft then you could be missing steps. Does your Y gantry move freely? Alex.
I’ve watched it and it’s the motor steps that are skipping. I adjust the current on the Blackbox and it gets better but still can’t do circles.
Other checks: - pulleys and couplers: make sure you have a setscrew on the flat of the motor shaft and that they are proper tight. - double check stop collars on leadscrews are tight against bearing, no distance between the collar and the bearings: they must be kept in compression - wheels tight so that its not loose carriages moving around unintended - hold endmill and give it a wiggle, shouldnt move. If it does, follow the tactile wiggle and see whats loose - belt tensioned - ran XY calibration wizards from OpenBuilds CONTROL > Wizards and Tools
Watching that 2nd video above, it sounds like there's a distinct lack of torque on the motors - the Y axis even coasts to a stop in both directions if you watch it. I don't know what motors you have but I would guess there's a lack of current going to them.
This morning I adjusted the current on the Blackbox, reset the Blackbox to factory default, calibrated the X, Y which were at around 95mm. Everything shy of standing of my head and having a witch doctor come in and help but nothing has changed other than the motors are no longer skipping steps.
No witch doctor needed. That image clearly shows mechanical backlash. Something is loose that shouldnt be. Check my earlier list and meticulously work through it. Stepper current looks very different and nearly impossible to be the case as blackbox at bare minimum will happily run a leadscrew machine
So I ran the circle cut CCW in comparison to CW and the bump-out is opposite side now. Cutout on the right is CW and left is CCW. FYI: I have the 1510 with belts, not lead screws.
As we have said - your pictures show a problem with your Y axis. The flat bits on your circles in the X plane means that the Y axis is not moving when it should. I see @Peter Van Der Walt has replied while I was typing - follow his advice. Alex.
I went through all of the V-wheels to make sure there was pressure but not too much pressure. The pinion is on tight as I cranked down on it yesterday to confirm. It still has the issue. I can move on of the Y-axis by hand when the machine is on. When moving the Y-Axis the pinion gear is moving also. Belts have plenty of tension.
As in motor shaft is locked ($1=255 in Grbl Settings) but pulley moves when you push on carriage? Well, then, see above (mentioned couple times) setscrews are loose.
Thanks for the confirmation. Did you make sure one is on a flat on the motor shaft? (i have to keep asking as we work issues like this all the time, unless you confirm i have to assume you did not and it could still be part of the issue. My old 1500 OX has the same pinion pulley setup and i get the pulley slipping on the shaft all the time. Eventually i superglued pulley on! But you are the guy there. From here i cant check it for you. You stand in front of it, use your senses to feel if the pulley slips on the shaft, or if the z axis tilts or if the whole gantry can move side to side. Feel whats loose by bumping on the parts... Did you make sure Grbl setting $1=255? Set it, restart controller to make it take effect. Motors should stay locked even when not moving. Then: (as before, work the list above)
Yep, the Grbl setting is there. Openbuilds has stopped responding to my email requests for help so I bought the parts to convert to a lead screw and hopefully, that will solve the issue. If not I will be purchasing a unit from Shapeoko.
Still very unlikely to be settings. We see issues like this all the time, and its something you assembled that is too loose. Got to grab that endmill and give it a wiggle, see what moves. Easy to give up, but better to find the issue. Its not 'because its belts' you can have the same symptoms on leadscrews if you dont address what is loose
I have grabbed the end mill and it is not loose. I went through the entire system and it all looks to be good.
Thank you for confirming (I asked before, twice, so didnt have confirmation yet... Now we can move on to the next step) Take the Y belts off and look at them from the teeth side while stretching section by section. If they were overtensioned you can break the reinforcing strands inside the belt, when you then stretch it you'll see spots where the teeth can move apart when you stretch that section of belt
Is there a change that before i replaced all the wheels/bearings that the belt overstretched due to the tension caused by the wheels?
I can't say for sure. You were there how hard did you pull it hehe. Its not "easy" to overtighten it, but we do see customers every now and then hold it with a pair of pliers for example,etc The motors won't stretch it if the wheels were tight. More likely to happen during assembly
Before I replaced the wheels and bearings it was very hard to push it. Now that they are replaced it is a lot easier.
What was the original issue? Forgot the precision shim between the bearings? That itself shouldnt break the kevlar strands. Like i said, more a case of the 200lb operator with a tool in the hand that causes that one. So lets assume that not it. I know you checked the setscrews on the pulleys are tight, but... Is the pulley tight on the shaft. Any chance the screws look tight but the pulley can still slip on the shaft: Lock the motors with $1=255 (Reset afterwards to make Grbl keep the motors always energised) then try twisting pulleys on the now locked motor shafts. Put in some elbow grease... the forces during direction changes can be quite extreme It could be X too: Thats leadscrew driven: Is the nut really tight on the plate? Anti backlash properly adjusted? Stop collars tight on the leadscrews and tight against the bearings
Yea the original issue was the wheels and I didn't forget the shims. Openbuilds is shipping me new belts today so hopefully, that solves the issue.
I replaced all the belts with lead screws and the Nema 17 motors with Nema 23 and it still has an Y axis issue. I suspect the blackbox is the issue.
