Layer Shifting

[ExplodedZombie]

Hi there, I have an issue with layer shifting with my Rostock Max V2. I have researched this issue for weeks without much in the way of results. Little changes here and there and still bad results.

About a quarter inch from the plate, things shift to the left. I messed with the belts and it seems a little better, but the problem persists. It seems like there is a little wobble in my most recent print until suddenly it straight up separates.

Rostock Max V2
Heat: 196 / 70 PLA
Print Speeds: 45ms, 150mm/s travel (tried to fix by lowering this from 200)
Belt tension: no idea how to measure but I easily fit my thumb between the belt and tower
Motor Curent: 140, 140, 140, 130 (default)
All joints seem pretty tight. Hot End secured.
Motor type: not sure but says Automation Technology KL17H... on sticker.

Will post a picture in a moment.

Original, terrible.
[img]https://i.imgur.com/BTXuXsB.jpg[/img]

Here is where I changed the tensions a little, and opened the bottom to get air to the motors. You can see it's a little wobbly all the way up.
[img]https://i.imgur.com/KCHAh9G.jpg[/img]

[rootboy]

Try bumping your motor currents up a bit. Here's how:

http://forum.seemecnc.com/viewtopic.php?t=7239

[ExplodedZombie]

Thanks for the advice. Wasn't sure if that was what I should do. Set it to the 155, 155, 155, 165 values which I believe is where it should have always been. I can try bumping slightly more, because it seems to be 'better'. The result of the change is that it is a little wigglier all the way up, but not nearly as extreme a shift.

[ExplodedZombie]

165 also has layer shifting. I'm wondering if the 32 Jerk and 1800/3000 accelerations need to change.

[rootboy]

You can try it, I always comment out the original line and leave it in there in case I have to go back to it. And the last setting on the currents line is for the extruder I believe, I would leave that unchanged.

[ExplodedZombie]

Well I tried lowering the acceleration and jerk and it seems to be about the same. At around the same height, things shift pretty hard then it straightens again. So I tested the towers, moved the effector around and figured that one tower was a little tight, one a little loose. I reset to Z position, which was oddly a bit low, but I figured it had to do with moving things by hand. Homed the printer and started printing. For the second time in a week, my printer head dug into my PEI and tore it up pretty badly. Not sure why that keeps happening. So I was pretty sure shifting would be better this time, and boom. I think it's time to throw in the towel and admit I just don't have this kind of skill. It seems so easy but I will likely be better off with an 'out of box' solution like the FlashForge or something like that. Happen to know a good place to sell used 3d printers? A smarter person than me could probably do well with this, given its many upgrades I added to try and fix the darned thing...

[rootboy]

First off, could you post your G-code so I can try printing it out on mine? I have a Max V2 as well, so they should be close enough that it should print on mine. The .STL file would be nice to have too.

As for your frustrations, I know what you are talking about, mine took years to get it to print nice and stable (or print at all). But it's there now, and it prints out pretty much drama free. Not that I'm making any recommendations, but this is what I've added to my V2:

PrintrBot Gear Head Extruder v2 (Simple version). This was added after my EZStruder simply couldn't cut it and I replaced it with something bigger (strapped to a NEMA 23 motor, no less). I've had a Wade's extruder (broke), a Prusa clone (kept wrapping the filament around the gear) and a few others. The PrintrBot has been essentially trouble-free.

.9 degree motors. Layers tended to look better after this mod. I also replaced the belts with ones that had steel wires in them. They ran okay, but were noisy. I switched back to non-steel ones (because of problems that I was having with my Delta Smart Effector). I also changed out the stepper drive sprockets at this time (it's simply not worth trying to get the old ones off to use them on the new motors).

New platform, carriages, and rods. My original setup had the pins holding things together, and on one of the axis the pin kept falling out. This was happening since day one... So I printed out a platform and made carbon fiber rods for it with the Traxxas ends. This did okay, but eventually the platform broke.

The original hotend got jammed for the very last time, and I installed a Prometheus hotend with a TrickLaser mount. It jammed up twice (both times due to operator error) in the entire time that I was using it. Highly recommended.

I upgraded from the Rambo, I can't remember why, to a SmoothieBoard. It never ran right and broke within the warranty period. So back it went. I replaced it with a Duet Ethernet, and aside from the Ethernet not playing nice with the USB (trust me, just forget about using the USB, you don't need it anyway), it has been fantastic.

I got tired of leveling the darn thing manually so I tried the FSR leveling system. It never worked right (something was hanging up and causing the bed to "tilt"), so I replaced it with the Delta Smart Effector, and when it worked (which was rarely), it was great. The problem was that it would trigger randomly, I eventually traced it down to noise from the power feeding the hotend. I now do the calibration with the power off to the hotend and it rarely has a false trigger. So now I've come to love the thing (other than having to give up my beloved Prometheus hotend). I don't even bother with doing a Mesh Grid Compensation, it's always right on the money.

For part cooling, I have a BerdAir. Works perfectly.

TrickLaser heat spreader. What can I say, it's a hunk of metal.

The stock power supply died after less than six months of use. Replaced with my 13.8 volt Ham Radio power supply. Things heat up nice and fast now...

And I replaced the spool holder. It kept getting hung up.

Other than that, it's all stock.

[ExplodedZombie]

Important update:
When moving the effector around to feel for a snag I noticed something funny. My Y tower would slip back down if I went toward it so that the Y-carriage was considerably higher than the others. It would fall about 1 inch. I tightened it up to where it would only slip a little at the extreme edges. We'll see... I have to fight that 'throw money at the problem by buying a new printer' feeling

Not-important update:
Wow! You have done way more than me.
E3D V6
Tricklaser Mount (32mm offset, don't remember what it's called exactly)
Tricklaser Heat Spreader (a must when it's kinda chilly)
LED ring bc why not?
Printed spool holder with bearings.
3 squirrel-cage fans for cooling, hooked in with the tricklaser mount, though I've always wondered if they are hitting quite right.

Nothing so far on the rods or carriages, they are the molded ones on the 'newer' V2s.

Before I dramatically sell my printer for $1000 less than I've paid for it, I will try a little more. I think I've ruled out the belts since it's almost always a shift in the same place.

[ExplodedZombie]

And as for the file, I can get probably put it in my google drive and share it in a pm.

[rootboy]

Hmm,

Try removing those fans and the LED ring to see if the extra weight is causing problems. And you should still be able to bump up your motor currents some more.

Oh yeah, this has been a labor of stubbornness, not love. But it's finally paid off, I just printed out a calibration block at .05mm. Layer-wise, it did great. The top and the walls "telegraphed" things like where the infill supports met the wall, and the top has bumps where the thin layer couldn't keep the plastic from expanding out from air pressure (I presume). I've printed out at least a dozen ornaments this weekend for a friend, and had one failed print. Not too shabby.

So send me the file when you get the chance, I'll print it up and see if it's a file related problem.

[ExplodedZombie]

No fans while printing PLA *aaaaaaaahhhhH!!!!*
I can try that for sure.
One last bit of information: Shifting only really happens on wider prints. Oh and I noticed that the hot end temperature, though set to 196, seems to drop to around ~193. Probably nothing but still not cool.

This article is interesting: https://forums.matterhackers.com/topic/ ... g-layers/2
- Every now and then there is a little pileup of filament but it's not huge. Seems to melt as its hit but could be a problem?

[rootboy]

It's in the interest of science. Speaking of which, a friend asked if my printer would autolevel a non-level bed (and print on it). It turns out that the Duet doesn't care, and did a nice job of leveling a bed that was raised by about a quarter of an inch on one side.

My Rambo board consistently was 5 degrees off on the low side. To fix it, I just upped the temperature by five degrees. It made getting prints to start in MC a bit tricky though...

The problem went away when I replaced the Rambo with the Duet. Now it varies by about .2 to .5 degrees (if it varies at all, usually it's spot on).

196 sounds a bit cool for PLA (depending on the brand of PLA, I suppose). I occasionally get the pileup issues too, and it's usually a sign that I didn't do a good job with the leveling, or that I'm printing at too high of a temperature. But when this happens next time, pause your print, and take a print removal spatula and smoosh it down to get it level again and let it cool, then restart your print.

That link reminded me to ask you to check your sprockets for tightness.

[ExplodedZombie]

Err...what do you mean by sprockets? The little gears on the motors? I checked everything I could for tightness but that was just the jiggle-test.

Using Matterhackers PLA. I can try 200 again.

[Mac The Knife]

Err...what do you mean by sprockets? The little gears on the motors? I checked everything I could for tightness but that was just the jiggle-test.

Using Matterhackers PLA. I can try 200 again.

Your statement "When moving the effector around to feel for a snag I noticed something funny. My Y tower would slip back down if I went toward it so that the Y-carriage was considerably higher than the others. It would fall about 1 inch. I tightened it up to where it would only slip a little at the extreme edges. We'll see... I have to fight that 'throw money at the problem by buying a new printer' feeling" Sounds like your pulley for the y tower motor is loose. The setscrew may not be sitting in the flat of the shaft.

[rootboy]

Err...what do you mean by sprockets? The little gears on the motors? I checked everything I could for tightness but that was just the jiggle-test.

Using Matterhackers PLA. I can try 200 again.

Yup, that's them. Shame they weren't loose... But take a closer look anyways. Just don't crank down on the screws, they won't take all that much abuse.

In other news, your part printed out pretty nicely. Which is also a shame, it would be nice to get to the bottom of this.

Would you like for me to send you your part? It's umm, purple (don't judge me, I was printing out Xmas ornaments before your print).

[ExplodedZombie]

Haha I also have purple! I printed an elephant for my son about a year ago and it came out great. Hmm if you happen to go to the post office I'd definitely pay for the shipping + some but I don't want you to go to any extra effort.

That does look pretty good. Would you mind throwing a few of your slicer settings? I'm using cura, btw
PS I'd be happy to get you the other files if you want to finish the robot!

Update: I have a theory! And that is: you are onto something about the weight of the effector & friends.
I upped the current to 175 and it seems to have minimized layer shifting. It's there. tiny bit.

Tomorrow I will remove a fan and try with same settings. Then 2 fans. Then 2 fans, 165 current because 175 is HOT.

But something I am noticing. Lots of scraping. Particularly when hitting small pileups but not always. I thought that retraction at 4.5, 60mm/s with Coasting enabled and a negative restart of .06 would help with that but it still occurs. Eventually I had to stop the current print because it's just too wobbly, but no *major* shifts.

[rootboy]

Haha I also have purple! I printed an elephant for my son about a year ago and it came out great. Hmm if you happen to go to the post office I'd definitely pay for the shipping + some but I don't want you to go to any extra effort.

It's no problem, I can ship them on Saturday. And I'm printing out one @ .1mm in black (I'm guessing that you scaled yours to 50%). Hmmm, 50% is too small. 100% is monstrous, what are you using?

That does look pretty good. Would you mind throwing a few of your slicer settings? I'm using cura, btw
PS I'd be happy to get you the other files if you want to finish the robot!

Is black okay? (Purple is still an option ). PM me with your address, but I think that you will be back in business shortly.

Update: I have a theory! And that is: you are onto something about the weight of the effector & friends.
I upped the current to 175 and it seems to have minimized layer shifting. It's there. tiny bit.

Tomorrow I will remove a fan and try with same settings. Then 2 fans. Then 2 fans, 165 current because 175 is HOT.

But something I am noticing. Lots of scraping. Particularly when hitting small pileups but not always. I thought that retraction at 4.5, 60mm/s with Coasting enabled and a negative restart of .06 would help with that but it still occurs. Eventually I had to stop the current print because it's just too wobbly, but no *major* shifts.

Woohoo! That sounds very promising!

And, yeah, ease up on the motor current.

And I forgot to list a crucial part in my saga, and that was the 713maker "Duet smart effector adaptor". Check it out, it's lighter than a standard platform, and the Duet Smart Effector is lightweight as well, and includes LEDs for lighting. Strapping your wind farm to it might take some noodling, but there is always the Berd-Air. And I'm getting error numbers of around .09mm with the Delta Smart Effector.

https://713maker.com/rostock/duet-smart ... or-adaptor

And I've included my PLA profile, but the print came out that good using your settings, not mine.

I exported my profile, but it only updates and stores a couple of settings in the profile. Weird... I'll take screenies of them tomorrow, but now it's time for bed.

Rostock PLA.xml.fdm_material.7z

(689 Bytes) Downloaded 521 times

[geneb]

FYI, if you're not doing a z-lift on retract (and thus travel), the nozzle could be striking the print and causing the layer shift. I seriously doubt it's the weight of the effector platform. Your travel speed could also be a factor - anything over around 220mm/sec on a RAMBo can be problematic.

g.

[ExplodedZombie]

My travel speed was 120 but I bumped it up to 160 because 120 is sad. I'll try using z-lift and see what's what.

[ExplodedZombie]

As for print size I'm printing at 60%

I just thought about something. The extra amount on restart (retraction)...I have that set to something like .4. Should that be -.4 (cura turns this orange)? It doesn't specify if positive means it pushes extra and negative means it holds back. If that is the case, though, it could explain why I have blobs on the top of my prints.

2 prints in a row have had very slight x/y shifts here and there, but one major Z shift. Tightened the belt since I discovered the head moved. Added Z-hop but I'm worried about that extra amount. Still hearing scratching even with 1mm hop

Super update: watched the print more closely and it really looks like every now and then one of the big moves that doesn't trigger a retraction leaves behind a length of filament, which I've seen one or two get dragged around until it piles up into a large hardened chunk that makes a loud sound when hit...

[rootboy]

I don't think so, mine is set to 0mm. But you could try it, just be sure to make note of your changes.

Ahh, next time watch the extruder and see if it is actually retracting. And it also has a screw that might need tightening.

[geneb]

...and when hit, it can cause lost steps, which causes layer shifts.

g.

[ExplodedZombie]

Yes. I turned combing to 'skin only' per a few comments I found buried in a topic. Makes sense because the head was making moves that didn't retrace, but were long distances, and left filament behind that then built up. Trying to start over and find really good retract settings for my e3d v6 using PLA, then I'll go back to trying to print the object with combing reduced.

[ExplodedZombie]

Would you guys mind sharing what you would set (in Cura) for the following given RMV2 + E3Dv6 (Bowden)? Here are mine
Temp: 200
Bed: 70
Retract Dist: 4mm
Retract Speed: 80mm/s
Retract Min. Travel: .8mm
Print Speed: 50mm/s
Travel Speed: 200mm/s
Enable Coasting: True
Min Volume before Coasting: .4mm
Coasting Speed: 90%
Combing Mode: Not in Skin

Thanks in advance.

[geneb]

What I would do is try the HE280 profile for Cura. You can get all the pre-built Cura profiles here: https://github.com/seemecnc/slicing-pro ... master.zip. The HE280 is very similar in performance to the E3Dv6, so it should work with no tweaking.

g.