After some issues with calibrating, this was the first print that started good. From the bottom to +/-12mm it is printed perfect. But from there to the top, it is printed really bad & distorted:
You also not a difference in color, and some tiny gaps. At some point, I noticed that the head was not printing on the figure anymore, but a few mm above. I think it may have skipped a layer, or a layer got detached during printing.
Is this because the print is to small? Or may this be something thats need tweaking more?
The strange thing is that my first prints did not have this issue. It just came out of the blue.
Things I have tried:
Checked all pulleys. I have tightened them. Because after that the issue remained, and I was not sure if the pulleys were the problem or not, I put a small line on the pulley and the rod, to see if during printing the moved. This is not the case. So the pulleys are where they supposed to be, and not shifting on the rods.
Greased all rods. I have applied a bit of silicone grease on all the rods, so they could slide easy.
Checked the belt clamps.
Checked if all belts are perfect straight & not touching each other & adjusted a bit.
Removed the stepper motors & refitted them, so the small belts are more tightened.
Adjusted speed, first from 6000 to 1500 (no effect), then from 1500 to 500 (90% of the print was good, but during last layers, it started shifting again, like in the picture in this post).
I suspect that on of the belts is jumping teethes, but I can’t figure out which one. Also, I made sure that there is some tension on the belt to avoid this.
Any other suggestions or tips how I can troubleshoot this?
Did you check that your X and Y are moving easily. Before mounting pulleys and motors on the rod, you must be able to move the head with two finger. If the resistance is too hard, the motors could jump some steps. Try a print at slow speed to confirm. (<50%)
You should check the reference voltage on the drivers for the stepper motors.
Also make sure the fan on the bottom is blowing and in the correct direction.
The cable that comes from the LCD screen make sure it’s not blocking the drivers for the stepper motors to be cooled.
today I finally had some time to do some tests again. What I did:
Lubricated the bars again
Adjust the belts a bit so they are perfect straight.
Checked the voltages of the drivers: perfect 0.9V
Adjusted cabling to improve airflow
Check the fan
Added an extra fan to blow air past the drives
Reduced all the speed settings to 50% in the software.
After this, I started a new print job, but no luck. After a couple of minutes, it started skipping again.
Any other ideas?
One of the belts (the one most to the back, so the one that I think is skipping) is not as tense as the rest (but not much difference). But how do I put more tension on that belt? The rods have a fixed place in the case, so it is not like I can move them a couple of mm to put more tension on it.
Have you checked if you haven’t a broken pulley?
I also had this problem and I found out that there was a broken pulley after fixing that one the problem goes away.
However, 2 days later I had it again but this time it was another pulley that was broken.
yeas, i’m sure about that. I have rechecked them now, and they all look ok. I also have put markers on the pulley, to see if they are not moving on the rod, which is not the case.
I’ve had something like your random shifting once. The printer started to print erratically. At the same time the LCD module was frozen. So I think the cause was an electric surge or rather a micro-power cut.
I’ve plugged the printer on an UPS and never got the problem again.
[quote=“raby”]Did you check the pulleys on the motors?
I’ve had something like your random shifting once. The printer started to print erratically. At the same time the LCD module was frozen. So I think the cause was an electric surge or rather a micro-power cut.
I’ve plugged the printer on an UPS and never got the problem again.[/quote]
That sounds more like heavy noise on the mains power line.
yes, I just rechecked and refitted the pulleys on the motors, but no result
Well, actually the device printer allready was on UPS, so I’m sure it is not coming from noise on the mains.
Does Velleman (or another company) offer any (paid) service for this kind of issues in Belgium? Is there somewhere I can go to with my printer and let them check it, to find out the cause and fix it?
[quote=“mitch2k”]yes, I just rechecked and refitted the pulleys on the motors, but no result
Well, actually the device printer allready was on UPS, so I’m sure it is not coming from noise on the mains.
Does Velleman (or another company) offer any (paid) service for this kind of issues in Belgium? Is there somewhere I can go to with my printer and let them check it, to find out the cause and fix it?[/quote]
today I finally had some time to do some tests again. What I did:
Lubricated the bars again
Adjust the belts a bit so they are perfect straight.
…[/quote]Did you loosen the belts to the maximum slackness you can? That’s what caused my missed steps, the belts had somehow tightened up after the first few prints.
Just loosen the hex bolts on the V clamps until you feel the belts are slacker. You might have to wiggle them about a bit as sometimes the belt gets trapped as the bolt is fastened. Do a print with them like that and see if you still hear the clicks. If that’s successful then you can increase the tension as you like. Mine are slack at the moment and print beautifully.
You shouldn’t need to change any software settings other than the odd tweak for particular filaments.
Did you solve this? I have the same problem. Prints are completely destroyed as X axis suddenly jumps. I’ve checked all belts and made sure the belt drivers are fixed. What’s next to try? Stepper drivers?
Is there any resistance as you move the head? There should be almost nothing and what there is should be even. No “sticky patches” or tightening towards one end of the bed. The stepper motors struggle if
a) there’s resistance (rods not parallel or belt pulleys not in right position on the rods)
b) belts are too tight (motor struggles to turn, starts missing steps)
Is there any resistance as you move the head? There should be almost nothing and what there is should be even. No “sticky patches” or tightening towards one end of the bed. The stepper motors struggle if
a) there’s resistance (rods not parallel or belt pulleys not in right position on the rods)
b) belts are too tight (motor struggles to turn, starts missing steps)[/quote]
Thing is I have printed for several days and it has been doing fine. This suddenly started. I did this, in order:
[ul]
Loosed the belt pulleys and make sure rods are parallel - no difference
Verified driver card voltage refs - X was a bit on the low end. Adjusted, but no difference.
Re-installed firmware. No difference.
Loosened belt tension a bit, including X motor. X belts were a tiny bit tighter than Y. Success, no more misalignment on X axis![/ul]
Test printing right now but it seems I’m on track again. Thank you so much for the tension tip! I still have calibration to do but at least layers stay where they should be. Lesson learned: belt tension is an important thing.
[quote=“ejeklint”]… Lesson learned: belt tension is an important thing.[/quote] It is, but just a word of caution, make sure you haven’t loosened those V clamps so much that the bolts can work themselves loose or that the belt can work itself free from the clamp over time. I had a seven hour print fail from just that problem the other day!
