Rostock MAX V3 Extruder Chewing Up Filament

[Ravitch]

I opened up a ticket on this issue, but since SeeMeCNC still hasn't replied to my open ticket 2 days ago I'll post here. You guys are awesome anyway, odds are someone ran into this. Cut and paste:

The extruder on my Rostock MAX V3 continuously grinds filament, to the point where I have to open it up for a clean out every 4-6 prints. The steps I've already taken to correct it are: Season nozzle, filter and lightly oil filament, triple and quadruple check extruder alignement, triple check correct filament temperature, slowed down print speed as far as 25mm/s. No matter what I do, every print will hit a point where it sporadically grinds away filament, leaving the extruder full of shredded plastic that finds its way into the Bowden tube and down into the hot end to clog it up.

End Cut and Paste

So, here I am ready to do more trouble shooting. I took the hot end apart and cleaned it top to bottom to rule out any contaminants, put a new .5 nozzle on, seasoned it, new filament filter oiled up, fresh out of the wrapper PLA that is measuring +- .03 away from 1.75 over a long distance. I'm using stock Matter Control Settings, but Simplify3D and Cura are both on hand (and both grind up filament). This happens more the bigger a part gets. Temperature doesn't seem to be the issue, I've pushed the new PLA to the point of excess stringiness so the nozzle shouldn't be choking up and unable to extrude causing the kickback.

I definitely appreciate any help with this. If I can't get it solved tomorrow I'm going to either buy a Bondtech QR, or sell this and change my strategy over to original Prusa i3 MK2's to scale my business up. When it prints it prints damn amazing and I've never had better layers, but starting to feel I'm not far enough in my 3D printing lifecycle to smartly and quickly play whack a mole with all the issues that pop up, especially since I'll be buying and building one to two of these a month.

[Ravitch]

I posted a pic of what the layers look like when the extruder starts kicking back and grinding. It starves the layers and makes them tiny.

[Ravitch]

My best Benchy ever!

Also, here are some additional tests I've done:

I disconnected the tube from the extruder to the hotend and checked if I could push through filament by hand easily into the hotend with no resistance. PASSED

Pushed filament through from the extruder end to the hotend through the bowden tube to check tube resistance - PASSED

Pushed filament through the bowden tube while connected to both hands to check for resistance - PASSED

Double checked PTFE tube in the hot end for defects - PASSED

Looking at this Benchy, my first thought would be something is wrong in the hot end, but I've already torn it apart and inspected. I'm going to do it again now.

[Xenocrates]

Here are some questions:

What plastic?
What temperature?
Does the hotend temp begin to drop as you feed plastic or turn on the cooling fans?
Has the hobbed gear been cleaned and inspected?

Depending on the plastic and temperature, it could be close to a point where it will extrude when first heat soaked from the warm-up and fail when actually printing due to insufficient ∆T, or a previously clogged hobbed gear may not expose enough of the tooth profile to grip well. In addition, a machining error might have left a poor tooth profile (it happened to e3d after all). And if the temp drops during printing or because of fans, it could use a retuned PID or insulation on the nozzle (or lower fan throttle).

[geneb]

"Season nozzle, filter and lightly oil filament" is the 3D printer equivalent of wearing a copper bracelet to help your arthritis. Makes you feel better, but does diddly squat.

I strongly suspect your issue is that the bowden tube isn't fully seated into the hot end.

g.

[Dale Eason]

I agree with geneb. It sounds just like the bowden tube isn't fully seated. I had the same issue at one time and swore the tube was all the way down. It got stopped by the top edge of the heat break and would go no further until I chamfred the edge of the tube with sand paper. Then oops it went in another 1/2 inch or so. Problem solved and it prints great all the time after I also reduced the retract to 2mm.

Dale

[Ravitch]

Plastic is PLA, freshly opened and the same roll printed perfectly on two other printers. Temperature is everything from 200 to 220, doesn't matter what it is set at it still does it. Normal print temperature for this PLA is 210 on all my other printers with no issues.,

The hotend temp doesn't drop, it remains stable now (after days of troubleshooting, thank god)

Hobbed gear has been cleaned and inspected, more times than I care to count. Also tried two new hobbed gears, same results.

I'm at a loss. I've done everything I can think of minus swapping out the the motor driving the extruder, and I don't have another motor to swap it out with.

Here are some questions:

What plastic?
What temperature?
Does the hotend temp begin to drop as you feed plastic or turn on the cooling fans?
Has the hobbed gear been cleaned and inspected?

Depending on the plastic and temperature, it could be close to a point where it will extrude when first heat soaked from the warm-up and fail when actually printing due to insufficient ∆T, or a previously clogged hobbed gear may not expose enough of the tooth profile to grip well. In addition, a machining error might have left a poor tooth profile (it happened to e3d after all). And if the temp drops during printing or because of fans, it could use a retuned PID or insulation on the nozzle (or lower fan throttle).

[Ravitch]

"Season nozzle, filter and lightly oil filament" is the 3D printer equivalent of wearing a copper bracelet to help your arthritis. Makes you feel better, but does diddly squat.

I strongly suspect your issue is that the bowden tube isn't fully seated into the hot end.

g.

On this I completely agree with you 100 percent, haven't ever done it on my other machines and they have thousands of hours combined time printing without issue. But it was recommended with someone having the same issue I am, so figured I would try it.

Not the bowden tube, I wish it was that easy. I measured and compared right next to my dissasembled second HE280 hot end, I'm seated all the way down. Unless it will drive down farther than 45ish cm, but that doesn't look possible.

[Ravitch]

I agree with geneb. It sounds just like the bowden tube isn't fully seated. I had the same issue at one time and swore the tube was all the way down. It got stopped by the top edge of the heat break and would go no further until I chamfred the edge of the tube with sand paper. Then oops it went in another 1/2 inch or so. Problem solved and it prints great all the time after I also reduced the retract to 2mm.

Dale

How far down is your bowden tube going? I'm 45 cm in, and looking at my second partially dissembled HE280 that looks like a full seat. Thanks.

[timskloss]

I'm 45 cm in

I think you mean 45 mm?

Once I had a filament that had thick spots over 2mm in diameter and it would get caught in the bowden tube causing a similar issue.

Anytime I see flow start off good but then slow and stop with a lot of pressure being applied by the extruder it is likely due to a gap between the bowden tube and the HE. I have a HE280 in a V3 and have had a gaps develop after printing solidly for hours after a reseating. Don't forget that after you insert the teflon tube all the way to the bottom you need to insert the retaining clip and press the tube in again to close the gap.

Chamfering the end of the bowden tube will also help it find bottom. You may also have residual material inside blocking the bowden tube from the bottom. This can easily be removed:

1. start with the HE already primed with filament.
2. let the HE cool down and solidify all the filament inside
3. remove the bowden tube retaining clip and press down on the release ring
4. advance the extruder by hand with the ring pressed down, the teflon tube should begin to rise as you advance the filament
5. I advance filament until the tube exits the top of the HE, but you don't have to go that far.
6. turn on the HE and set it to your extrusion temperature
7. As the HE is heating up, gently pull up on the filament/tube while pressing the release ring pressed down
8. when HE is hot enough, the filament will suddenly release and you can pull it all the way out
9. turn off the HE heat and examine what you pulled out. If there is a ring of material that is larger than 2 mm in diameter, then you had a gap.

This should pull out any plastic that has accumulated in the HE. I once pulled out a plug that had multiple colors of filament in it.

[Dale Eason]

How far down is your bowden tube going? I'm 45 cm in, and looking at my second partially dissembled HE280 that looks like a full seat. Thanks.

45mm may be right. To be sure take a 1/16 drill bit and go in from the top make sure it clanks on metal at the bottom. Then measure how far it went.

[Ravitch]

Hahahaha, I meant 45cm! I have the Rostock Max V3 Part Daddy Mod Edition, it's got a gigantic throat!

Thank you very much for the succinct write up. Following your steps I pulled out an almost 5mm wide 1mm thin disk shaped gob of stuff. I just got done printing a perfect calibration cube, now on to something bigger. Thanks again Sir, I realize it took you a while to write up a detailed response and I definitely appreciate it!

I'm 45 cm in

I think you mean 45 mm?

Once I had a filament that had thick spots over 2mm in diameter and it would get caught in the bowden tube causing a similar issue.

Anytime I see flow start off good but then slow and stop with a lot of pressure being applied by the extruder it is likely due to a gap between the bowden tube and the HE. I have a HE280 in a V3 and have had a gaps develop after printing solidly for hours after a reseating. Don't forget that after you insert the teflon tube all the way to the bottom you need to insert the retaining clip and press the tube in again to close the gap.

Chamfering the end of the bowden tube will also help it find bottom. You may also have residual material inside blocking the bowden tube from the bottom. This can easily be removed:

1. start with the HE already primed with filament.
2. let the HE cool down and solidify all the filament inside
3. remove the bowden tube retaining clip and press down on the release ring
4. advance the extruder by hand with the ring pressed down, the teflon tube should begin to rise as you advance the filament
5. I advance filament until the tube exits the top of the HE, but you don't have to go that far.
6. turn on the HE and set it to your extrusion temperature
7. As the HE is heating up, gently pull up on the filament/tube while pressing the release ring pressed down
8. when HE is hot enough, the filament will suddenly release and you can pull it all the way out
9. turn off the HE heat and examine what you pulled out. If there is a ring of material that is larger than 2 mm in diameter, then you had a gap.

This should pull out any plastic that has accumulated in the HE. I once pulled out a plug that had multiple colors of filament in it.

[timskloss]

No problem. I am glad you were able to get back to printing.

This seems to be the most common issue with this printer. Somehow my bowden tube works its way out slowly every few hundred meters or so of filament and I have to clear the plug. No sure why this is happening, but not a big deal now that I know what to look for.

[Ravitch]

No problem. I am glad you were able to get back to printing.

This seems to be the most common issue with this printer. Somehow my bowden tube works its way out slowly every few hundred meters or so of filament and I have to clear the plug. No sure why this is happening, but not a big deal now that I know what to look for.

Mine came back after I said it was fixed earlier much like yours, after one long 20 hour print. I have since fixed it (fingers crossed, printed almost 30 hours straight and it hasn't come back. This was after making sure, I marked the Bowden tube's placement in the throat, and then used a camera to video tape and time lapse a 14 hour print. What I saw was that the pressure of being connected with the HE connector in the same whip very slowly worked it up out of the throat, even secured with the lobster claw.

I took my filament out of the hot end whip cable after watching that, and loosely secured the hot end to the whip with zip ties. Video'd another long print and time lapsed it, and it is no longer working itself loose, so looks like a fix.

[smgvbest]

HI, Well this is my first post and I'm having this same issue. I did clean my hub gear off and reseated the bowden tube in the hotend. After reseating it I measured and it was ~45mm for it to bottom out, checking before it was in about 35mm. Now I have not done the cleaning up the hotend as above. I"m running a test print now to see what it does. I'll do the cleaning step above regardless.

FYI, Mine is also a Rostock MAX V3, finished building it Saturday night. first print was good, but 2 prints later it started making a clicking/grinding sounds in the EZRStuder, checking the EZRStuder, I noticed the hob was full a plastic and shavings were at the top of it. Got the raspberry pi inside running octoprint/octopi, wireless is working but didn't at first, that was because the instruction while having put in the SSID and password doesnt enable DHCP by default so it was using a default IP. enabling DHCP in /boot/octopi-network.txt fixes that.
here's the change for those interested
## WPA/WPA2 secured
iface wlan0-octopi inet dhcp < Was manual
wpa-ssid "YOUR_SSID"
wpa-psk "YOUR_PASSWORD"

Very nice having a 3d Printer with WiFI


One thing I've noticed still is sometimes the BED temp isn't maintained. like right now I"m printing PLA @ 220 and a Bed temp of 60. the the reported temp is 48-49, other times it maintaining the 60.

[Ravitch]

Good luck brother, I thought I solved it and had a good solid week plus of flawless printing and it came back, and nothing I have done troubleshooting wise will get rid of it this time. I have two HE280's and both of them do the same thing. Either I'm unlucky or the design is garbage (solely speaking about my HE's). I'm swapping to an E3D V6 to get it flawless again, then I'm not touching it again unless its to demo it to sell it.

Luckily, in the last couple weeks when it was up I got a lot of swords printed, so it paid for itself plus some looking at it monetarily. But the amount of time I invested is a personal loss.

[smgvbest]

oh, that doesn't sound good.
I got one good print last night, no grinding. then started one this morning and it sucked, grinding from the start.
I'll check it when I get home and clean it fully this time and check if the Bowden tube moved

[dajay23D]

when you say grinding, is the teeth skipping over the filament? So the filament is stuck and the teeth repeatedly grinds until it breaks? Or does the filament fall out of the grooves in the extruder causing it not to align

[dajay23D]

when you say grinding, is the teeth skipping over the filament? So the filament is stuck and the teeth repeatedly grinds until it breaks? Or does the filament fall out of the grooves in the extruder causing it not to align and therefore grinding.

[Ravitch]

The problem is, if your issue is anything like mine, that the gap is so small that the plastic disk it starts making is so thin that you can measure all day long and won't be able to tell. You just have to tighten the bowden tube down, say a prayer, sacrifice a unicorn, and hope its seated properly. The issue, that was causing me money and tons of time, is that you might go 6 hours of printing, then hour 7 that tiny disk building up and choking the filament out hits terminal mass, the extruder starts grinding, print quality goes to crap, and you are out that print.

oh, that doesn't sound good.
I got one good print last night, no grinding. then started one this morning and it sucked, grinding from the start.
I'll check it when I get home and clean it fully this time and check if the Bowden tube moved

[geneb]

A "tiny disc" won't cause that issue, but using too-long retracts in PLA certainly will. Might in ABS too, but I don't print in ABS enough to have a handle on it.

g.

[smgvbest]

when you say grinding, is the teeth skipping over the filament? So the filament is stuck and the teeth repeatedly grinds until it breaks? Or does the filament fall out of the grooves in the extruder causing it not to align

When I say grinding I mean it sounds like it's chewing up the filament. it doesn't break it. but if I pull out the filament and inspect it the side against the hob is chewed up and roughened. the hob is filled with filament shavings and I"ve cleaned it a few times. I've checked and rechecked it's in line with the filament. There is a district click sound also when it does this I've noticed.

When I cleaned it last time, it printed a 3hr job flawlessly, then the next time a little 30min print job failed totally.
I pulled the filament out of the hotend and it had a small disc on the end of it. I"m working on cleaning it out again and reseating the bowden tube.

I've not seen this as something many have complained about, I've seen the issue of seating the tube correctly so I do believe either I did not assemble the he280 correctly or am doing something wrong. I've thought about opening a ticket on this and asking if i sent in my he280 if they could check it out and test it to see if its my assembly causing the problem. I've ordered a assembled he280 to kind of test this out myself. I'm not someone who thinks its a makers problem until I've been ruled out as the cause.

I do love the printer, when it's working its great. and the build volume, wonderful.

I did read here someone mention adjusting the retract distance, I use Simplfy3D for my slicer and send the gcode thru octoprint same as i do for my flashforge creator pro.

Since that was brought up, I've looked and it has a retract distance of 6.5mm and a speed of 6600mm/min
where as my flashforge I have 4mm and 1200mm/min could that retract speed or or distance be to great perhaps?

[smgvbest]

I've adjust the retract distance, cleaned and adjusted the hot end according to this
https://seemecnc.zendesk.com/hc/en-us/a ... lament-JAM
if I print small parts I don't seem to have problems but printing something larger. the first layer starts fine then it goes to pot after that.

Here you see what happens, yes its starved for filament. its making that click sound frequently during this print
You can see it started fine in the upper right of the photo is where it started printing then it went to down hill until I aborted in the second picture.

I ran about 5m of filament without the hotend and no issues noticed. th issue was after running that and cleaning and adjust above.

any idea's or should I look to open a ticket with tech support?

[geneb]

I strongly suspect you're suffering from a poorly seated bowden tube. If the tube isn't fully seated into the hot end, a small "puck" of plastic will develop between the end of the tube and the bottom of the hot end. This causes no ends of issues - mostly feed problems.

g.

[ComJak]

I had this issue as well before and regardless of the bowden tube, it would fail. The thing that fixed it was buying a new hobbed gear from SMCNC. Fixed all my problems right up.