Bent Frame

[Tim_bc 2]

Hey Guys,

So......

I've been using my Ultimaker 2 Extended for a while now, and have been very happy with the performance of the machine....

Well, until about 3 days ago I've been very happy.....

Long story short, I've had a few requests for larger prints, and this was the first time I was going to do a print which covered basically the entire print volume. I kept getting failure after failure, and could not understand what was going on.

I've checked the glass and it has the slighest warp in it, and I had a screw that was not completely flush with the print bed. So I fixed the screw hole and made the screw flush, recalibrated everything and failure after failure again....

I did some reading, and found a few threads here about people experiencing simliar issues, and after spending the last 3 days have come to the conclusion my frame is bent. It wasn't until now I've discovered this because all of my prints have generally been a small footprint, and they turned out great....

I've done the typical loosen all screws holding the frame together and tried banging the corners with my hand trying to encourage the frame to become square, but it simply does not seem to want to happen. I've also had a significant amount of trouble trying to find a perfectly level spot to do this... Any suggestions on this?

I've tried squaring the frame several times, and each time after tightening the screws I experience the same issues..... I know for a fact my bed is being levelled properly as after I run through the routine I check it with a level in all three dimensions and it comes out perfect.... So it must be the frame not being square right?

This is becoming a serious pain in the ass, as I have had to cancel some prints for people because the printer cannot reliably print a large footprint...

Does anyone have any suggestions how to approach this problem? Because honestly, the printer does me no good if I cannot print large volumes. I might aswell bought a Go.... or regular Ultimaker 2. The benefit of having the larger print volume is null and void.

I'm seriously getting frustrated as I need to figure this out.

Any suggestions would be greatly appreciated. At the moment, my biggest challenge is trying to find a spot that is perfectly level to square the frame..... Also, when I do find a spot that is perfectly level, how aggressive should I be in banging the frame? It appears everything I've done so far has had little to no effect whatsoever....

Thanks if advance!~

[xeno 108]

To get e better idea what is going wrong, please post some images of the failures.

it might be totally unrelated to the frame

[chrisw 70]

The frame is only made of flat panels. It can be perfectly square but the rods/pulleys/belts/bearings can be misadjusted or damaged and can cause problems like you're describing. I wouldn't apply force trying to straighten anything out, because usually you only need tools to make adjustments to these machines.

And like @xeno suggested, post some pics of print failures!

[gr5 2,172]

You can print larger. You aren't supplying any photos or strong evidence of non-planar glass or non-planar rods/gantry so first I'm going to assume that the problem is your parts aren't sticking well and by the time you get to the 30th layer the part is peeling off the bed. Not sticking. This is easily fixed. But you have to ask how to fix that issue.

Alternatively you are correct and your gantry is warped enough to cause problems. Please print just the skirt of a large print and photograph the skirt. If you are right there should be areas of the skirt that are overly squished (transparent) and other areas that aren't squished enough (ropy) and areas that are perfect (pancake). One fix is of course to increase your bottom layer thickness. This is one of the reasons bottom layer is typically .3mm (much thicker than the others). But there are other solutions.

Both of these problems (large parts warping off bed and inconsistent bottom level) are fixable and can be dealt with. Lets confirm which problem you have first (maybe you have both but I want to see the bottom layer skirt only first).

Edited June 27, 2016 by Guest

[Tim_bc 2]

Hey Guys,

Sorry guys, I was in a rush and frustrated when I wrote the question....

I'll take some pictures tomorrow after my exam, and go from there.

I have verified my rods are square to each other with alignment tools, and the bed is leveled perfectly according to a 3d level.

gr5, how your explaining the birm is exactly what is happening. Currently, I have the initial layer set to .3 to try and help with initial layers. I've tried manually adjusting the bed on the fly, but can never seem to get the correct balance on these larger prints. Once again, I'll print off the brim tomorrow after my exams and take a few pictures to post.

I've also talked to the shop manager at school and he has confirmed I can bring the printer in there to square the frame, as he has several locations where there are 100% level surfaces to use.

Thanks for the responses, and I will print off the brim tomorrow to post some pics.

Thanks again,

Tim

[gr5 2,172]

Well I recommend you start with the official leveling procedure but do it such that the nozzle touches the glass just barely at all 3 points.  Knock the glass up and/or down a bit so you can hear where it just barely touches and doesn't touch the glass.  Particularly the front two points.

That gets you level.  Then you want the correct distance to the glass.  From that position you can probably print as-is.  For large prints which warp off the glass very easily you want to squish the hell out of the plastic.  Here is a visual guide:

You want it squished almost as much as the transparent yellow skirt above but not that much! You want it somewhere between there and the blue one. if some areas on the plate look like the red or even black bottom layers above and others are like the blue/red/yellow above then you will have a problem where the filament isn't squished as much. Also going to .4mm bottom layer may help you out. Also use the BRIM feature in Cura - this is critical to keep corners from lifting on large parts. 5 outlines of brim is usually enough.

Also use glue and clean the glass. The glass needs to be cleaned every month - get oils and dust off the glass which reduce the ability of the plastic to stick. And put a little glue stick ont he glass and spread it around with wet napkin and wait for it to dry (hot bed dries faster).

Take a photo of the bottom layer brim - especially zoom in on problem areas wher brim is too thin or thick so I can see if your glass is "saddle" shaped or just tilted or if it's good enough.

Edited June 28, 2016 by Guest

[Tim_bc 2]

Thanks a lot for the tips!

Great info!

I have been using extra strength hairspray and glue sticks, and this has never been an issue before. I can only assume due to the large footprint it is showing the slight leveling imperfections....

I was going to pick up some elmers wood glue later today to give that a try based on reading a different thread where you mentioned it was your favorite.

Overall, I love my printer and it performs very well on small to medium sized footprints, but these larger footprints have just been a nightmare for me.

I'll get some pictures later today and post,

Thanks again!

[Tim_bc 2]

Ok,

So I finally had time to print off the brim today and get a few pictures.

I apologize if the quality of the pictures is not very good, unfortunately, I only have my phone, but if you need better quality pictures I'll try and borrow one from a friend.

https://drive.google.com/folderview?id=0ByQ6OKsy-cVCT0VZVjdVX245T1E&usp=sharing

I shared the pictures from my google drive, unfortunately, I wasn't sure how to add them here :/

The top left and top right are pretty big differences in layer height, well at least it appears so. top right is squished nicely, but the top left is a bit ropey so to say.;...

If these pics help identify what anyone may think is going on I would greatly appreciate hearing your thoughts... I have myself pretty convinced at this point, but I'm nowhere nearly experienced as most of you guys

Thanks!

Tim

Edited June 30, 2016 by Guest

[peggyb 170]

the thing is: when the first layer is there, even when it is a bit off, the rest will follow in paralel of the first.

As for safety you can tape the brim to the glass, especially in the sharp corners (don't push to hard on the tape or you will lower the bed a bit).

Always watch the first layer and turn the bed screws on the fly when needed, you can even manipulate the bed with you hands, just to push from underneath or on top at the difficult spots.

[Tim_bc 2]

Hi Peggyb,

That's pretty much exactly what I do now to be honest. The pictures is the best I could get the brim adjusted too. Some areas are squished nicely, and other areas are a bit ropey... It's the whole reason I think my frame is not square. The bed will be levelled 100%, and yet I still get an uneven brim/first layer.

I know there is also a slight warp in the glass due to a screw not being 100%, but the good folks at Ultimaker have sent me a replacement for that, so fingers crossed when I get the glass and re-square the frame again things will come together.

In the mean time hopefully someone who has also experienced this situation will be able to provide some insight/advice as where to go.

Thanks again for the response!

[chrisw 70]

The large brim doesn't actually look too bad to me. What type and brand of filament have you been using that exhibits this problem? And what have your bed and nozzle temps been?

[Tim_bc 2]

Hi Chris,

Keep in mind this is with a 0.3 initial layer, normally I try to do a much smaller layer to be honest. Plus, I have attempted to square the frame on several occasions, and it definitely seems to have helped.

I've been using ColorFabb almost exclusively since I've started printing. I just like the silky smooth appearance it gives when it's done correctly.

For this brim, I believe I actually raised the initial layer temp to 215C after reading what others do. I usually do my brim at 205 because I tend to print slowly, and after the initial layers, I will go 195C with 20mm/s print head speed. The heated bed is at 65C, I've pretty much stuck with the bed temp at that since I started. For some reason, I was never able to go below 65C without issues....

After some additional reading, I've made up a batch of Elmer's wood glue with water mixture that gr5 was talking about in a separate thread. I have to admit, I'm pleasantly surprised with how strong it seems for adhesion...

The part I've been having trouble with, I've decided to give another go after another attempt of straightening the frame, and armed with the glue/water mixture. It's a 36-hour print, and I only have 10 hours to go, and things are looking very promising thus far... Fingers crossed

I'll post a pic when it's done

[gr5 2,172]

If the back left corner is too low (as you describe) and you don't want to affect the top right corner then move the front right down by turning CW. This will lower front right a bit but also raise the rear left. Maybe you should just do the official leveling procedure first to get the paper feeling EXACTLY the same friction at all 3 points and only then adjust the 3 screws and always turn them the same distance.

Then try printing a brim or skirt all the way around the outside to see if it worked.

If it still is bad only in one of the 4 corners then remove the glass and check for bumps/screws protruding under the glass. Maybe you have to counter sink one of the screw holes. Or you can *add* warp to the glass by putting a thin washer under one of the 4 corners to compensate for any warp in the overhead mechanism.

[Tim_bc 2]

Thanks gr5,

Eventually was able to get the large footprint prints to stay put, but it has been a struggle.

My semester is wrapping up in 2 weeks, so I am going to spend some time fine tuning my printer big time.

I really appreciate the responses, thank you very much.

Cheers,

Tim

[brianskyze 3]

Well, I have problems with my UM3 frame aswell.

I'm a beginner and up until now, I did a few test prints on a smaller scale (let's say 5cm3). But I wanted to print some bigger models since I'm using it for architecture and I will need almost full print volume.

Starting my big volume printing with a model of a famous bird feeder that can be found over at Thingiverse. When it started printing brim plate I have found out that my first layer is not the right height. On the front side, the PLA didn't stick on the bed and in the back, there was almost no material on the bed. I have realised my bed is out of level although I did automatic levelling before printing. (Cura first layer height setting was standard .27mm)

Assuming auto levelling does not work properly I have decided that I will level it manually. Since UM is sort of foolproof it should work smoothly, but it didn't. I have struggled with screws turning for a full hour incorporating all of the ideas found on this forum (especially turning the wheel instead of the screw at the precise levelling at the back of the plate). Didn't work at all. Whenever I've started automatic levelling right after it has failed.

What I did is I have designed UM3 dial gauge holder to manually and accurately level the bed. Again small scale print of my gauge holder was more or less successful. I have levelled the bed with a gauge and proved it with the help of spirit level. It was levelled. I have also proved my glass if its straight and it was.

I fire up the auto levelling it fails again. I'm freaking out. I head over to the forums, there are users reporting that Z-axis alignment is off and that they change .gcode before every print (I don't know about this procedure, so I decide to drop it). So being a little encouraged by the forum I sincerely believed auto levelling is a complete rubbish.

I head over to my UM, fire up my print of the bird's feeder and I encounter the same problem. The base level should be .27mm in height but it was ranging from .13 - .43mm, (I should mention the brim was curved and there were no rough angles). I have also tried to fine tune the bed while printing the brim. And in 20minutes time it was unsuccessful.

Totally freaked out I'm starting thinking my table where my UM is places is completely off balance. Today I build a small support tray with adjustable legs. I fix it on my table, I spirit level it, it is perfectly aligned. Clearly feeling good about it I put my UM3 on top. And this is what I see:

https://drive.google.com/open?id=1s-4fSrCqzmemsdyknm3XTxU19BoiFVn_

My UM3 frame is bent :angry:

A closer look:

https://drive.google.com/open?id=13SzAq54JS8Lfj174qYrRGtyV-JlVHBLx

The front right corner is 5mm in the air. And one could see with his bare eye that it's off. So I went to read this thread, tried to loosen the frame screws, didn't do much. (note: I have bought UM3 assembled)

I have taken some measurements to support my theory of bent frame.

• Front frame plate_ difference in height between left and right vertical edge: 2mm (like it is cut wrong)
  
• Front frame plate_ difference in diagonals: 8mm
  
• Housing plate up to Y-axis guide hindge_ difference in distance between left and right: 3mm
  

All measurements were made with high precision tools that we use in the firm. Capilers, dial gauge, laser distance measures, ultra-sensitive spirit levels. So there is little possibility of a measurement error.

I am highly convinced my main printer frame is bent. Do you have any ideas what can I do? Have some experienced the same stuff?

I'm sorry for a long post, but this is my first time posting and since I'm just a beginner I don't know what are the focus data to provide you with a good picture of my problems. On the other hand, I'm sorry for my rough English (I'm not native).

Thanks for any kind of help!

Cheers,

Brian

[gr5 2,172]

First let me say the printer itself does not need to be level. It will print on it's side. Or upside down. or any angle just fine.

Yes it looks like your frame is bent. You could either send it back or just loosen all the screws a bit and force it into the right shape and re-tighten the screws. The problem is always shipping so sending it back and getting a new one might not help as the same shipping service will be used. Somehow these shipping services all seem to hire elephants that like to stand on the boxes.

You should at least be able to get the print very close to level near the 3 screws, right? It's the rest of the print bed that is tough.

If the bed is "saddle shaped" compared to the gantry (move the nozzle around to test) you could potentially twist the glass a bit with washers and clips into the same shape such that the nozzle prints pretty flat on the bed. Better though of course to fix the gantry (which is usually just as crooked as the box itself that the gantry sits inside of).

[brianskyze 3]

gr5 thank you for your help!

I have already tried to loosen all the screws and tried to brute force the frame down. No effect whatsoever.

The print inside the triangular area of the screws is decent but far from expectations from 3000+ euro device. I have encountered problems when I print two pieces that should interlock by screwing mechanism. The "bolt" was tilted off the Z-axis and they didn't fit. First I thought my print settings were bad and I tried a few times but didn't work out.

I am aware that frame does not have to be levelled, but I did my adaptive mount to eliminate one of the possible failures.

My main concern is that the front plate of the frame is actually machined wrong. Because the difference between left and the right vertical edge is 2mm. Meaning that the front plate corners aren't all at 90°.

I'm not sure if I understand word GANTRY correctly. Is this the metal rod the print head uses as a guide? Or is this the metal rod driven by the motors?

Thanks, Brian

[gr5 2,172]

Gantry consists of the 4 outer rods, and the two rods that go through the head, and the belts. These should all be parallel to the bed. But if your printer was positioned up on one corner and an elephant stepped on the opposite corner then your front frame indeed would no longer be all 90 degree corners and the gantry is no longer all parallel to a plane and instead saddle shaped where two opposite corners are higher than they should be and the other two opposite corners are lower than they should be.

My friend neotko calls this situation "banana". some people call it "saddle shaped".

One fix is to send it back.

another fix is to put the same saddle shape (banana shape) into the glass. Using washers (as shims under the high corners) and binder clips (to hold down the low corners). This is fine for errors < 0.5mm but much larger and you will be printing saddle shaped parts - parts with a saddle-warp all the way from the bottom layer to the top layer.

Ideally you want to fix the warp. Other people on this forum have fixed this by loosening screws and pushing really hard. That's all I know. I have no personal experience. The problem is *not* Ultimaker but the shipping service.

[tomnagel 126]

I think you should send it back. I would recommend to contact your reseller.

[brianskyze 3]

Thank you all. I have contacted my reseller. Will keep you updated.

Regards, Brian

[brianskyze 3]

Well, it has been over three months and I finally got my UM back from the reseller.

 

I was correct, the front panel was bent therefore replaced. Now it seats perfectly levelled on my desk, I just need to do some big area test prints to ensure it has resolved all my problems.

 

Regards, Brian