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tmrevlje

First print - UM Robot some issues

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Hi guys,

 

I am a new user of Ultimaker 2, after settling some kinks, the material wouldn't move, so I had to push it a bit for the feeder to grab it and push it on its own, first print I added apparently not enough glue, so it got unstuck in the middle of the print job. But after that stuff I was able to start printing the UM Robot.

 

In all honesty, for the first "out of the box" print it went well, however I do have some issues which I am sure are an easy fix for a skilled user.

 

The robots legs started off very nicely, up to his body it looked like I hit the loto with an out of the box print, but then there were some gaps in certain layers and also some stringing, not much but you can see on the pictures, where the outer edge of the body begins, there's some strings hanging off.

 

I would kindly ask you to help a noob out and give me some tips where or how to fix this, I used the UM Robot 3D model from the SD card, should I have put the model into Cura first and do some modifications there or what?

 

Thanks in advance.

P.S. What format of images are allowed? I uploaded the photos to an external link and tried adding it here, but it says: You are not allowed to use that image extension on this community. I used JPEGS. Is it possible to upload the photos up here on the forum or should I always use an external file hosting service?

Can't seem to find a button in the editor where I could attach a photo :/

 

 

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Here is a video on how to upload images:

We know it is not the easiest way, but it is what we have atm...

Can you upload an image of the robot?

Most likely you have to go into Cura and slice it again because the gcode on your SD card is ok, but not great.

I think in your other post I already gave you some guidelines.

 

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should I have put the model into Cura first

 

Yes! :)

Please update what country you live in - it's in profile settings.

The UM Robot is a tricky print but you barely need glue - probably no glue needed if brim feature is on (recommended). Probably you just need to level again - you want the first layer to be pushed into the glass slightly.

For overhangs you need to print cool so make sure all 3 fans are working. The side 2 fans should come on before the first overhang. If you want a good quality robot I recommend 220C and 35mm/sec. If you want a stunningly perfect robot you have to print 2 side by side, shell thickness .8mm, speed 20mm/sec temp 200C. Make sure retraction is on.

Oh - and to get the antennas perfect it helps to print 2 robots at the same time (tools --> 'print all at once'). Or barring that turn on "cool head lift" in expert settings but printing 2 robots if you want a stunningly perfect robot.

It's hard to print at 200C and colder without also slowing down because the plastic gets thicker like molasses.

You will find that you can have functional low quality parts that are just fine for most things at 100mm/sec printing or very nice looking parts at 35mm/sec. It's a tradeoff.

 

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but then there were some gaps in certain layers

 

Sounds like underextrusion. Also fixed by printing slower. Make sure your filament isn't tangling and it helps a ton to put the filament on the floor (when the filament enters the feeder at a sharp angle it causes 3 problems related to underextrusion). If you are printing .1mm layers at 20-35mm/sec you don't need to put it on the floor but it's still a good idea to avoid grinding up that black feeder on the back of your printer and having particles end up in the nozzle.

Red spool

 

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@ gr5 thanks for the lengthy reply, appreciate it. Now a few newbiesih responses:

1.) I only see two cooling fans, so I am not sure where the third one would be.

2.) In Cura I can see the speed setting, but failing to find the Temperature setting, can you please point me to that?

3.) How can I define when to turn on the cooling fan (you said for the overhang parts to have them turn on at that stage)?

Thanks!

P.S.

Sorry for the double post and thanks for closing the other one.

 

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Snap. When I was even more nooby than I am now, I too could only see two fans. The third one is the one you hear immediately you switch on the UM2. You can see it by looking at the printhead from the back side of the printer. It's central and a bit lower then the others.

Incidentally, whenever I click one of your images to see a larger version I get "you do not have permission to view this image"... kinds of defeats the point of posting it! :) (I assume you've marked them as "private" or something like that in your gallery).

 

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it helps a ton to put the filament on the floor (when the filament enters the feeder at a sharp angle it causes 3 problems related to underextrusion). If you are printing .1mm layers at 20-35mm/sec you don't need to put it on the floor but it's still a good idea to avoid grinding up that black feeder on the back of your printer and having particles end up in the nozzle.

 

Hi George. Do you have a topic somewhere that expands on this?

 

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Hi George. Do you have a topic somewhere that expands on this?

 

Um - off topic question - sorry but it's kind of a lot to read - many hundreds of posts:

http://umforum.ultimaker.com/index.php?/topic/3976-almost-always-missing-layers-underextruding/

Definitely read this first post:

http://umforum.ultimaker.com/index.php?/topic/4586-can-your-um2-printer-achieve-10mm3s-test-it-here/

And some interesting solutions (although I haven't modified anything on my UM2 and it prints fine):

http://umforum.ultimaker.com/index.php?/topic/4393-ultimaker2-feeder-system-improvements-and-ideas/

 

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The 3rd fan is in the back of the print head. Look at the print head very carefull. Feel for a breeze. It's very quiet but it comes on as soon as you power on (even before the lights).

Set the level where the fan comes on in Cura - I like to have it on full by 1mm. Default should be 5mm. It will come on gradually so as not to mess up the nozzle temperature controller with a sudden change in heating requirements. Make sure fan is 100% min and max.

nozzle temp, bed temp, retraction distance, retraction speed are all controlled on the UM2 itself (usually - there's 5 ways to control temp). On the UM2 you can select what temp to use for PLA and change it and save it back into the PLA material memory position.

Or you can just hit PRINT and before it starts printing you can go to the TUNE menu and change the nozzle and bed temps there. I recommend 5.5mm for retraction, max retraction speed (35?), 220C for a good medium safe average nozzle temp (190-240 are reasonable printing temps depending on print speed).

Oh and bed temp should be 50C to 60C.

 

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Thanks for the tips, used all your settings, now after the first robot (well actually I had this problem prior to the printing of the first robot as well) is that material just isn't coming out of the nozzle, the head is moving as it wants to print, but nothing is coming out.

On the first occasion, I just gave it a little push and it started feeding the material to the print head and came out, had to do this procedure about 3 times.

Now I changed the material (Colorfabb's Traffic Red) and the problem is here again, when it purges right before the print starts, it comes out but curles up, so it's not flowing nicely down towards the print bed. But then it stops coming out at all...

Mind you when I set the settings back to Factory Settings and go through the leveling and material insertion process, at the stage, when the material should come out it comes out, with a bit of an upwards curling (sticking to the nozzle head), but it comes out nevertheless, however when I got to printing, it doesn't come out... weird.

Any suggestions?

Thanks

P.S. Thanks Don, indeed my Gallery was set to Private, silly mistake. Made it Public now.

 

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the head is moving as it wants to print, but nothing is coming out.

 

Need more information - there are too many causes.

Often there is just a small air pocket in the nozzle and if you wait a bit the filament will come out. Is the feeder moving forward (black thing - back of machine)? Can you see the filament moving?

One possible (unlikely) failure that happens sometimes: the sleeve on the feeder is too loose so that it won't turn.

Another - the filament got ground up (consider tightening the feeder a little - see Robert's guide - I linked to it above - post #13).

 

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Checked it, the feeder is moving, the filament however is not, I will try to tighten the screw to put the white indicators to the middle. As I have read in Robert's great list of tips, my printer is after the mid-March date production and the white indicators are still set into the upper most position. The feeder is not pushing the filament as it should.

 

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On UM2 menu system: ADVANCED MAINTENANCE MOVE-FILAMENT.

Something like that.

Move it backwards. If it won't go backwards then you ground it. Heat nozzle to 180C, cut power, pull firmly on filament out through the back. Although if it isn't ground I usually heat nozzle to only 90C before pulling it out.

The feeder motor offers almost no resistance when moving filament by hand. As long as it isn't powered (which is almost always if you aren't printing but difficult to predict).

 

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Ok so, I have tried tightening the hex screw by the feeder as stated in Robert's cool guide, should the white indicator be lowered by screwing the hex screw? In my situation no matter in which direction I screw the hex screw the white indicator remains in the upper most position (low tension). Is that normal?

Thanks

 

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Damn it, when I get everything else right, the material is feeding out nicely, then my objects after 5 minutes of printing (with a brim around it), starts moving around with the nozzle. Is this a bed leveling problem, because I did put glue on the bed but not enough? It's weird though when I removed what was printed and touched the glue surface it's really not gluey, there is no resistance on the surface, so I am guessing the glue dried off instantly?

I'm baffled, and tips? You mentioned earlier that I hardly need glue on the bed, if I brim?

 

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This means the bed level is too low.

If you relevel the bed, set it in a way that it is just barely not touching the nozzle.

What you have now wouldn't have been solved by glue, or you would actually have needed to glue your part to bed.. :p

Set it a little bit higher and the heath of the bed will make your print stick to it throughout the entire print.

Sounds like you are getting there!

 

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Sander! Thanks!

Yes I am slowly getting there, thanks to the amazing and quick reposponses from you guys. I went to print another UM Robot and it seems to not have the same issue as the Pikachu model from Thingiverse, but I did relevel the bed in between :p so if the UM Robot works now and has no issues I will attempt the Pikachu later with the same settings..

Don't ask, my brother wants the Pikachu :D

 

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