I think I have a slight tramming issue Gary. After calming my nerves and clearing my head I realized before I can do anything I need to get the tramming issue fixed. I found a good method on YouTube and am headed to harbor freight for a dial indicator and Menard's for some jig material. Once I have my tramming dialed in as close as I can get it I'll start in on the calibration. I have a Duet Controller from Ooznest so the process is a little different. Today I gather and prep. Tomorrow is full on calibration day.
I'm very familiar with the Duet 2 controller (not so much with the RRF3 based firmware from Ooznest if you have a Workbee Z1 +, but I know people who are) - do shout out if you get stuck with anything. Alex.
See Benjamin Vg 's threads here https://openbuilds.com/search/127757873/ - he also had a lot of trouble dialing in a Duet based Workbee
Peter that link did not work and I would love to read it. Can you repost it please? Thanks for the heads up Alex. I tried to do the calibration technique Ooznest has on YouTube and I can't get an accurate number. I think it's because of my tramming issues. I have my materials for tomorrow so wish me luck guys.
Sorry, seems I can't make it a direct link. Click om Click the Postings tab, then scroll down and click the "Find all threads by Benjamin Vg" link
I can't see why tramming would be an issue with the calibration. In my mind, if it is an issue, that means that your spindle is not solidly mounted and can wiggle. When I calibrated my machines I never used the tip of the bit, stuck in the spindle, to calibrate. I chose a point on my gantry and measured from there. The tamming issue I solved separately and independently from the calibration. If your machine is set-up/constructed differently than my machines then ignore me!
Okay... Although it appears as though I fell of the face of the earth that is not what happened. I DID however fall *** over elbows on November 29th fracturing my pelvis. So I'm laid up and can't work on my tramming. I'm still healing and dealing with a lot of pain. So I once I'm healed I'll get back to it. And as usual I will keep you guys posted.
Thanks Peter. I appreciate it. Since I've been mostly sitting and having nothing better to than think I did come up with some things that might be contributing to the issue. One is my hose for my dust collection is zippy tied to z axis stepper motor. I wonder if that is pulling on the gantry and skewing my cuts. Next I suspect that one of the screws on the Y axis is binding at it gets closer to one end of the machine. Again I wonder if this is skewing the cut as it moves. The reason I suspect the Y axis is binding is as it gets closer to me something starts squeaking loudly. What are your thoughts guys. Could either of these issues contribute to my problem?
This might help with the dust hose issue :- Swing Arm Re the squeaking - have you lubricated (dry ptfe or silicone spray ONLY - no oil) your leadscrews? Check that leadscrews are straight, not being pulled out of alignment, bearings and lock collars properly seated and bearings/shims etc arranged in the correct order. Alex.
Thanks Alex I'll look into that Swing Arm a little deeper. The squeak doesn't happen from the home position to almost 2/3rds the length of the Y axis and then the last 1/3rd it squeaks. I could lube the screws if you think that would help but to be honest it almost sounds like the 3 washer bearing you put on the end that squeaking. I haven't isolated the exact location the squeak is coming from but is sure sounds like it's coming from there. Would you say that is or is not a potential bind?
The thrust bearings Ooznest are using are not really up to the job - if the bearing proves to be the issue look here:- AXK0821/AS0821 Budget Needle Roller Cage with 2 AS Washers 8x21x4mm Simply Bearings Ltd Alex.
Would these be considered an upgrade? Any ideas on how should I go about determining that it's the thrust bearing that is squeaking?
Yes- these are needle roller bearings - much greater surface area than the very cheap ball bearings used in the original. Of course, if the bearing is the issue and your machine is still under warranty Ooznest should replace it - check all the bearings before you do a warranty claim if that is the case. If the thrust bearing is faulty it will probably fall apart if you dismantle the locking collar. Alex.
Okay we are long over due. Long story short I'm still laid up and can't stand or walk for more than a few minutes. I can sit and lay with no pain. Have to have surgery but with workman's comp in the middle of it I'm at least 45 days out. Minimum. Anyway between me and my son we have gotten the spindle trammed. My dial indicator has a radius of 165mm. At that distance I am trammed to 0.05mm. Is that tight enough or do I need it dialed in tighter? Remember I'm only cutting wood and will be doing inlays and signs and things. My day today started with milling the spoil board so it matched my spindle. Well... I didn't take Alex's advice and get those thrust bearings bought and it finally blew out in the middle of my job. So I'm down. Ordered parts before I came here and they will ship on Monday. Not sure how long it will take them to get here so... I'm on hold at the moment.
So does anyone know why or what is stressing that screw enough to burn up that thrust bearing? I bought bigger better bearings to replace them but I feel I need to address the source of what is chewing up that side of the CNC. I don't think it's happening on the other side.
Over tensioning the leadscrews can do it, but I've had quite a few reports of the ball bearings supplied by Ooznest failing - the ball "races" look super flimsy. I can't fit mine 'till I get some longer leadscrews but, on my Facebook group, several people have swapped to the bearings I linked to and say they have no further issues. Alex.
Awesome Alex good to know. I bought 10 thinking I'll replace all of them and have extras should they fail in the future. and I'll remember not to tighten my screws too tight next time.
So while I'm waiting on parts I'd like to take a little time to discuss Backlash. Which was brought up early on in this thread before a whole slew of issues cropped up. I am now trammed. I have removed the flex in my bench and re-configured my dust collection hose. I have some flexible coupling upgrades ordered as well as better thrust bearings. Once I get my parts I'll calibrate the machine and mill the spoil board. Then I'll cut that test block. I'm hoping you guys can translate the findings and then tell me what needs to be done to the machine to correct it. Typically what is done to correct backlash on a machine? I have read what causes it but how is it addressed on a Workbee?
Depends what the cause is - backlash in the leadscrew is inevitable, and is corrected using the nut blocks (X and Y axes) and the anti-backlash nut (Z axis). To adjust the nut blocks, loosen one from the gantry plate, squeeze them gently together and re-tighten. For the anti-backlash nut on the Z you use the adjusting screw. The aim is to have each nut block (or section of the anti-backlash nut) touching either side of the thread, but not gripping it tightly. Other causes are down to something being loose (like motor couplers) so the motor turns but the gantry doesn't move. When you have everything adjusted, trammed and calibrated try cutting (with a very light, shallow cut so you don't introduce tool deflection into the equation) a circle and square with the diameter of the circle the same as the side of the square - the circle should touch the sides of the square exactly in the centre of each side. If you think you have issues post a pic with the X and Y axes labelled and we'll take it from there. Alex.
okay... so I blew out a thrust bearing on my Y-Axis and purchased the needle bearings Alex recommended. For right now I have just replaced the 4 bearings on the Y-Axis screws. When I run the gantry the full length of the machine there is a lot and I mean a lot of noise. Almost sounds like it's binding. Different octave levels of squeaks. Should there be a lot of noise when moving back and forth? It's not even under load. What can be done to eliminate or at least diminish the noise. Or is it supposed to be that noisy?
dry lube helps, make sure your anti-backlash nuts are not tight.. should just have the play taken out with the screw. When you are running a job and cutting it will be much louder than the squeaks. Gary
Wow thanks Peter that was an awesome video. It cleared up the mystery around eliminating backlash should it occur. So those blocks are just tight enough so there is no play when you move from one direction to the other? Right now I have them tight... Real tight. I hope I haven't messed them up.
