Hi
I’ve just finished building the printer but I’m a bit stuck with the setup. I found the instruction very good in general although I sometimes missed some text between the large images.
X/Y
AUTO HOME now works fine mostly, but often there’s a juddering with the Y-AXIS just before it hits the sensor.
X-Axis can be moved manually without problems normally, but that has occasionally started juddering around 20-30 cms from 0.
The Y-Axis is a big problem though. After AUTO HOME it can be moved from 200 to 20, occasionally with a start judder. When it’s moved back manually to home it usually stops short of the y-end sensor, even thought the display shows 200. After that moving back to 20 it goes too far. This accumulates with each manual back-front-back.
If I move X towards 0 then start moving Y it sometimes won’t even start moving…
I checked pulleys and motor mounts and made some adjustments that at first seemed to work but not for long. I also oiled the rods.
What causes the judder normally - lack of smooth motion on the rod or slipping belts?
I notice the belts aren’t completely in the cable tensioners they stick out about 1mm. Could that be a cause? I had quite a problem getting those mounted anyway.
What’s confusing is that sometimes it seems OK and I think I’ve solved the problem, then on the next test it goes wrong again.
Z calibration
Finally, the build platform is not level - if I set the 1mm mentioned in ‘calibrating z-axis’ then move X or Y the printhead is grounding by about mid way. I adjusted the z-height to about 1mm at x=0, Y=20 in the end and I’ll adjust the rest using the thumbwheels, if it works…Does this sound normal…?
I’d be grateful for any tips. I had a couple of issues with some steps due to misreading or not reading carefully enough but I think I recovered. I hope I don’t have to start again - lots of nuts & bolts
The mounts that hold the belts may be to close or to far away from each other.
The screw that hols the pulley to the motor may be loose You should check all of the other screws in the pulley as well
Make sure the X an Y bars are alined.
You find instructions under tightening the belts.
What you are seeing with the Z axis may be normal.
It sounds as if you have not leveled the bed yet with the thumb screws.
OK thanks for that - I guessed there probably wasn’t a quick fix…
For the Z-axis issue the instructions should perhaps be changed - start with much more than 1mm gap and check the gap on all 4 corners, then fine tune with the thumb screws. On the first attempt I definitely grounded the head moving from home - hope I haven’t damaged it.
You were right, the bed mountings were slightly out - I noticed there was some play when assembling but didn’t adjust for it:-(
Re XY - from some other posts I think my problem is the pulleys. I noticed some had a very tight thread for the m3 set screws and I think either they aren’t fully tight on the rods, or the threads have stripped and they don’t grip. I just tried to tighten a couple and they are definitely slipping now…
I will try to order new ones, or find some better ones, although aluminum seems to be the only choice
Had a surprise boxing day - the first print attempt (vertex logo keychain) worked fine and I produced 2 further prints >1hr & >2hr.
My previous issues were due to a bad alignment of the back right Y-axis pulley, and a too-tight belt on the y-axis motor. In addition the build platform hadn’t been mounted perfectly (thanks your tips Wrong Way). This morning I got the z-axis calibrated surprisingly quickly and printed the keychain…
At the start of the keychain print the m3 set screw on the back left y-axis pulley fell out but the print continued without hitch. Afterwards I tried to reinsert the screw but the thread was obviously stripped. The 2 subsequent prints didn’t seem to suffer, but I will definitely request a replacement pulley or maybe a full set as the others will probably fail as well sometime.
I will also print a couple of h60’s alignment gadgets http://forum.velleman.eu/viewtopic.php?f=58&t=13210 so I can keep track of any drift on the y-axis pulley with the missing screw,
To be honest after the initial problems I was amazed that it actually printed without trouble and the results seem good. With narrow ‘pointed’ objects it slips into a frequent ‘waiting…’ status, which was worrying at first, I assume it’s allowing the printed filament to cool when it has to print fine objects? - so far I’ve found no info about this status.
yes that will be one of the next things to look at.
In general it seems to be working well at the moment, touch wood.
Occasionally it will suddenly shift in the +X direction, usually after the hated ‘graunching’ noise. It sooms to go unstable when printing several items that involve a lot of longish fast movements.
Since yesterday afternoon it’s been printing several flat objects each about 2hrs, so it’s done about 8 or 9 hours now without issues. I discovered rafts, which has helped an awful lot - the first of these prints had to be stopped due to warping.
I am surprised how well it is working now, especially as one Y-pulley has no set screw, the other on the same belt has a stripped thread and I’m not sure how the other pulleys are. I ordered a replacement set yesterday, and I have created an stl to print my own pulleys if I get into problems again
Also I found that the bottom screw was missing from the Y-axis endcap above the X-motor - the one that’s impossible to reach without taking everything apart I assume that could allow some additional movement on the rod…
Next is to replace the old noisy fan at the bottom
I must admit that there is a lot of useful info on the Forum and I’m learning a lot about 3D printing, mainly that it’s not like conventional printing where you can put in the paperand it will print every time.
but the print continued without hitch. Afterwards I tried to reinsert the screw but the thread was obviously stripped. The 2 subsequent prints didn’t seem to suffer, but I will definitely request a replacement pulley or maybe a full set as the others will probably fail as well sometime.
I assume that could allow some additional movement on the rod…