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thevictor11

Print falling over

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So I've started printing a small figure and I noticed at about the same area both times I come into the room and it's either on it's side or just at an angle and there's just PLA string everywhere. Anyone come across this issue?

This is the figure I'm trying to print but at x2 the scale.

tumblr_mdzfshsxEf1rcmyjeo3_500.jpg

These are some of the settings I'm printing at if it helps at all. The settings I've changed are the ones I've underlined, everything else is default.

ACCURACY

Layer height 0.1

Wall thickness 0.8

Enabled retraction

(Retraction settings)

Min travel 5mm

machine center x 100

machine center y 100

I'm going to try the print again without the retraction and see how that goes.

SPEED/TEMP

Print speed 50

Print temp 220

[EDIT] This is also the first time I'm printing off the SD card.

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The reason that's happening is because it's such a tiny area gripping onto the tape. Any little small bump of plastic that has cooled down and gets caught on the head will just tip it over. With the perfect settings you should of course not get any bumps but hey, no one's perfect. You can help it stick better by cleaning the tape with some alcohol to get rid of any waxy and or oily stuff on it.

You can also turn the z-axis screw a tick to raise the bed as it's laying down the first layer. This will really force the plastic into the tape and make it grip better.

The easiest and most reliable fix though is probably to just add a very thin base to it that you simply bend/cut off when the print is done.

Ideally of course your printer and gcode would be perfect and never leave any tiny bumps for the head to catch on. It's doable, I've printed some pretty thin tall stuff without having it topple over, but you have to be a bit lucky as well.

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I finally caught it in the act. It usually happens when it starts printing out the crotch and I noticed it got caught on a bump like you said.

What settings would I adjust for that issue? I'll make a base for the figure as well just incase.

EDIT: Made a fairly wide base for the figure and has been printing for about 2 hours. Because the base went out towards the arms the support wall for the arms had been shrunk to a small rectangular pillar. About knee height for the figure I noticed both of these pillars were wobbling quite a bit when the extruder was printing on it. In a panic I went with the first idea that came to mind.

a6.jpg?psid=1

Glue gun the heck out of it. :lol:

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You can try the "skirt" feature - when you set it to an offset of 0 (Zero), it will form a "brim". I think Daid recommends a line count of around 15-20.

That should be easier to do than to alter the model :-)

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The day you start worrying about wasted material is the day you'll stop printing :D I have a hole grocery bag full of failed prints, off cuts, test prints etc etc. You just have to try to put it out of your mind and go for it :)

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The day you start worrying about wasted material is the day you'll stop printing :D I have a hole grocery bag full of failed prints, off cuts, test prints etc etc. You just have to try to put it out of your mind and go for it :)

This is true. This is gonna be an expensive prototype :lol:

Skirt is just being printed now so we'll see how this turns out! I heard that 5th time's a charm (very reliable source)

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So after another attempt at printing this figure, it's fallen again.

It tipped over at the crotch again, for some reason I guess a bump catches the nozzle and it pushed the figure off. The skirt is still connected to the platform, unmoved. I looked over the model in Cura and I didn't see any problems at the waist area. There are some red sections but those are near the neck.

I'm not sure what to do now, it's been 7 prints and every one of them has fallen over in the same area. I tried a quick print prior to this one using 0.3mm layer height and the speed set to 75mm/s and it printed flawlessly. I normally have it at defaults using 0.1mm layer height and 50mm/s speed.

Appreciate it guys :oops:

AN extra note. I've printed a few other things as well and none of them has had any issues with the nozzle catching.

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Strange. Have you checked to make sure your filament measurement is correct so that it is not over extruding?

Also, I just looked at your picture again and it looks like you have some melted plastic on the side of the nozzle, is your nozzle leaking? If it is and it's dripping molten plastic onto the print that could certainly cause a bump for the head to catch on.

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I've taken my digital calipers to the filament a few times after each print just to make sure. I've been adjusting the diameters between 2.78 and 2.82. I'm not sure how much of a difference that makes. It was default at 2.89.

The build up was cleaned after that last print. It stays clean up until it messes up where the nozzle spends a few seconds getting caught in the print and covers itself. I sped the print up from 50mm/s to 65mm/s to see if that makes a difference. Will update in 2 hours, general time frame when it fails.

UPDATE: Okay it takes 3 hours before it messes up. Woooh :( Anyways. I noticed after so long the Z axis didn't lower enough to clear the print and the nozzle started scraping the against it. I held on to the print to see if I could manually lower the Z axis just a little bit but it bumped the print off before I could. Very frustrating.

Also the nozzle is still clean, no drips or blobs hanging on it. The diameter is still the same as when the print started from what my calipers tells me.

Not sure what to do other than completely redo my 3D model in hopes that the model is the problem and not the settings despite it working on a low quality print.

Any suggestions is greatly appreciated :)

Managed to get my camera working and took a few snaps of the print and the previous one. I'm not sure if this would help at all but worth a shot. Mind the puns, sorry.

DSCF0536.jpg

DSCF0535.jpg

Also, I'm not sure if this is just a small detail or not but I noticed the skirt prints almost like a cone. The outer edge is on the platform but as it prints more layers it slowly starts to rise. If I let it continue until it filled itself in, it would look like a cone. :?:

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Mhh, just a wild guess but also check the coupler for the Z-Axis (that barrel with the 2 grub screws). Maybe the Z-Axis slips a bit in the coupler and doesn't lower enough. (Never heard of such behaviour, but worth a try).

Other thing can be that the hot end is a bit loose and turns and lowers a bit while printing. (Just guesses here)

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I'm not sure how to lower it manually and get an accurate measurement each time. Maybe I can do it through cura?

I was thinking of just going back to the start and recalibrating EVERYTHING I can. Make sure all the belts are properly adjusted, check all the screws and everything is in the right position.

Quick question for the extruder. How tight is the screw supposed to be? I'm pretty sure I have it at a good tightness but I'm not 100% sure.

This time zone difference is unfortunate. The waiting is killing me haha. Really appreciate the feedback though. Everything helps, if I find anything wrong, even though it doesn't relate to the current problem is a plus. :mrgreen:

NOTE: I printed http://www.thingiverse.com/image:183945 and it did the same thing that happened to my model. I had done about 2 hours worth of printing before that one and just before the point where it would've connected the 2 side pieces it kicked it to the side. On my second attempt I caught it and manually raised the platform and it worked fine from there but left a weak spot in the print. If anyone wants to give it a try and see if that happens to you as well then I can confirm that it's my model which would be unfortunate and kind of awesome. It happened at 19% completion. It's labeled RIGHT CLAW.

NOTE2: I'm not sure if this matters or not but prior to the first attempt at the piece mentioned above, I printed http://www.thingiverse.com/thing:32510. At the tip, about 95% of the way through the print I noticed it just failed to print 1 side of model. I'll post a picture of it later when I get home from class. Didn't think to document that when it happened.

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Is it happening at the same height each time? I don't know it might be a long shot but try disconnecting power and manually turn the z-leadscrew and see if it's smooth all the way. Maybe something is catching and making the platform stick temporarily. Seems very unlikely but I'm sorta running out of ideas.

When I talked about manually lowering the bed before I meant by using Pronterface that is included with cura. It gives you a "control panel" for the printer so that you can jog the head around, feed plastic manually etc etc. At least I think it still comes with cura... I haven't used it in a while. As for measuring, a caliper is a great tool to have and even the digital ones are cheap and accurate these days. In a pinch I guess a ruler could do the job if you lower it a large amount each time to spread out the measurement error.

Again, this is all a long shot so..yeah..

And yes, timezones are a bitch :D

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It's pretty close to the same area each time. Happens usually just before the crotch or right at it. Roughly 3/4" window where it will have an accident. I'll give the control panel a try when i get home from class, completely forgot that existed once I started using the Ulticontroller :lol:

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Quick question. I noticed this while I was just tightening the belts. Is the Z axis screw supposed to just hover under the hole? I questioned it when I built it but never bothered to post it. That seems to be the only issue I can find so far. Gonna give the Cura control panel a test.

WP_001818.jpg?psid=1

UPDATE: So I tried the Cura control panel to slowly step it down by 0.1mm at a time and see if there were any inconsistent drop rate and this is what I got.

Z +

002.20

002.30

002.39

...

009.39

009.50

...

037.50

037.59

it's the consistent all the up to where I stopped at 080.09

So I'm not sure if that would ever make a difference in the nozzle getting stuck. The print usually messes up around the Z045.00 - Z055.00 range.

I've tightened all the screws relating to the Z axis I believe. The 4 on the motor at the bottom, the 4 for the cylindrical thing that the motor and Z axis is connected to annnd....that might be all I can think of.

Pain in the arse. If anyone ever printed off that Makerbot piece I linked in an earlier post could they let me know if it went smoothly? I'm going to try it again now and see if it happens again there. If not I'm hoping whatever I've done in the past 2 hours has fixed this.

UPDATE2: So printed the Makerbot claw but this time connected directly to my PC. No issues at all, no weird steps, no jumps and no catching. This may be looking up. Will try the figure again tomorrow but connected to the PC.

This is starting to feel like those experiments I did in high school where I recorded everything I did haha. Maybe this will help someone having this issue if it works. :D

Cheers!

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So I believe I may have found the problem. The bumping starts when it starts printing the hands of the figure. I guess because it's such a small area to fill in that the PLA warps and angles upwards which is what gets caught. That combo'd with a tower of support material being the only support structure it has doesn't give it a very strong platform. Does this sound right to people with more experience? I'm not quite sure how to solve this issue. Would a better fan duct help? I noticed while holding the print steady for 15 minutes that the default fan duct doesn't blow directly onto the area the nozzle just dealt with.

Any suggestions would be awesome :D

UPDATE: I noticed the support structure on the right side, that is barely hit by the fan, is much more wobbly than the left one. Does being cooled make the plastic sturdier than cooling gradually?

Also this is the model I'm trying to print. Finally got a decent render of it.

tumblr_mec5sp2rTM1rcmyjeo1_500.jpg

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Thanks Owen. I'll give KISSlicer a try.

The printer just got its power unplugged because my dog ran and tripped over it :cry: Going to give the new fanduct a go and see how that goes. Also give KISSlicer a go for the next attempt.

It's usually cats that are giving the problems around here :roll:

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Luckily my cats know better/don't care haha. I've been meaning to look into getting another fan during the holidays. I'm just curious where you would plug the second one into?

You need to wire it into the 1st one. I used a plug and 2 sockets to make a double adaptor

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Luckily my cats know better/don't care haha. I've been meaning to look into getting another fan during the holidays. I'm just curious where you would plug the second one into?

Cats are a purrrfect way to ruin a print:

IMG_20121103_101230.small.jpg

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