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zorpiedoman
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Below was my ranting post from two days ago. After cooling down for a day, I just did another print run. I cleaned the bed with rubbing alcohol and made sure the nozzle was clean as well. I decided to use a cube as a test print.

It printed PERFECTLY.

"Well," I thought, "It must be the rubbing alcohol. So simple!"

Then I went back to printing my other design after cleaning the bed and the nozzle.. guess what? It could not even draw the first circle of the skirt!  I even tried again with the print speed reduced to 20%. It still got about half way around the circle then got loose from the bed.

ARRRRGH!  Help!

----

Before I start ranting, let me be clear: I was well aware of the patience and time that might be needed to set up a 3D printer before I finally pulled the trigger and bought this one. This one had the very best reviews, but I had no expectations that I would just open the box and it would print.

But it's been FOUR DAYS...

I watched two different videos for how to assemble the printer. I took my time and checked and re-checked every step. I made sure it was perfectly level and the vertical frame is square within 1mm. All the rollers move smooth and the belts are properly adjusted. Everything looked perfect.

I spent over 30 minutes making sure the bed was perfectly flat and adjusted. All four corners had a very slight bit of resistance when a piece of paper was placed between the nozzle and the bed. Perfect.

The next three days have been spent trying to get it to print. No matter what I have tried, the material will not stick to the base. Again I have watched countless videos and red many articles on how to make this work. I have cleaned the bed, I have sprayed the bed with hairspray. I have adjusted the tempature of the nozzle and the bed dozens of times trying to find a setting that will work. I have adjusted the z-offset. I have cleaned and even changed the nozzle. NOTHING WORKS!

It seems this thing always leaves tiny blobs of material. When it start's its print run and makes those lines up the left side, there is always a blob at the start. It often goes a couple inches before it appears to finally 'stick' to the base. when it lifts up to move to the middle, there is a hair of material it leaves behind. Then it starts to draw the skirt... again starting with a tiny blob, which at times I feel gets caught on the head as it tries to pass by. But more often than not, it cannot even complete one circle without the material picking up off the base and getting dragged across. On many test runs it also looked as if the material on one side was thinner than the other side indicating an inconsistant flow of material. 

A couple times it somehow got past this point and even started printing my model. A simple round object. I'd watch closely as it made it past the first layer or two... exicted that maybe this time it worked. But inevitably something would go wrong, material would get dragged across the model without sticking or something would catch the print head and the whole thing would get dragged around.

Dozens and dozens and dozens of times I have tried to get this to work. Checking and re-adjusting over and over again... Can you see why I'm at wits end? 

I don't even know what to ask for in regards to help. I just think I need to pack it back up and return it.

Sadly and with great frustration,

John

 

PS I'm still using the sample filament that came with the printer.

This topic was modified 9 months ago 3 times by zorpiedoman
This topic was modified 8 months ago by zorpiedoman

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bigheph
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@zorpiedoman

 

Dont give up. Its a learning curve but once you get used to it you will find it a very fun hobby and will learn alot along the way.

 

Firstly, I assume you are using Cura to do your slicing. The line down the left and the blob at the beginning is completely normal. The blob is usually caused while heating up the nozzle to temperature, PLA is a very drippy material. It will leak out of the nozzle slowly when getting up to temperature and not moving. The line it prints down the left is like a nozzle purge. This gets all the filament up to printing pressures and cleans off the leaky blobs you saw when getting up to temperature. It is similar to the skirt you are also printing, just add an extra prep step before printing. This is a good thing as when it moves to the middle to start the print you will have less issues than if you just started the whole process from the middle.

 

Bed leveling is a MAJOR first step to ensure your prints are sticking to the build plate. I use the bed level Gcode from here ( https://www.thingiverse.com/thing:4559687/files ), it will move the nozzle to all 4 corners then the middle in a step by step process so you can adjust it at each point. Works like a charm.

 

I had a warped bed on mine that dipped significantly in the middle of the build plate. To compensate for it i was leveling my corners extremely close so the middle would be at a workable height. It really sounds like you may have a similar issue or you just arent getting close enough on your leveling. If you are using a sheet of paper to set your nozzle height (80gsm paper = 0.1mm thickness) try using the backing film from a label or sticker or even baking paper to adjust your nozzle height (all usually about 0.05mm thickness).

 

Also make sure your bed temperature is set correctly. PLA will stick nicely at 60-65 degrees on the glass build plate of a V2 without any glue or hairspray.

 

If you are still struggling, try putting a layer of blue 3m painters masking tape on the build plate. This will also give you another 0.07mm of height to help compensate if you are still calibrating your nozzle too far away. And PLA sticks like a mofo to this stuff, i had a couple prints i had to knock off with a hammer. LOL!


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3nderUser
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The best clean bed to start with, is simple to clean it with dishwasher soap and rinse it under hot water and let it dry natural or blow dry when having an air compressor.
A tissue with rubbing alcohol can dissolve the grease from your fingers and you unnoticeable will spread a layer of grease al over your bed instead of cleaning it.

As said above, use a high bed temperature, even 75 degrees is fine to go with. After the first layer sticks well you can lower the temperature in the next layers. Also start with higher nozzle temperature like 210 degrees for PLA and lower that a bit in the next layers.

Observe the printer doing the first layer. It really has to squeeze the first layer onto the bed and not just lay down a trace of plastic.


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zorpiedoman
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Thank you for your replies and suggestions.  They really helped. 

 

First, in regards to a possible 'warped' bed, I could not see any warping when I held a straight edge on it, but when I did the calibration I set the corners to have a bit more than slight resistance on the paper and when I put the print head in the center the paper could move freely. So perhaps the warping is so slight you cannot see it?

To get a successful print, I set the z-azis adjustment at -.03, and run the first layer at 10mm speed, and the temperatures set at 210 and 75. After the first layer they go back to 200 and 60 and the speed goes back to 50mm.

I will be fine tuning some of the other settings in Cura as I learn more about them. We'll see how it goes.

Thanks again,

 

John

 


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Demon85
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I just figured out the same on my 1 week old v2.

When leveling I set the corners very tight, the paper can barely move, but still on the middle it moves freely... Is this normal? Like every bed works the same, or should I return it?

Second, is that normal that after every print I have to readjust the leveling? When the print is finished I often check the leveling on the home position out of curiosity, and the paper either moves freely or can't even push it under.. I heard that others don't even touch leveling for months, so it's a bit frustrating.

(Also having a layer shift problem on the y axis like many others, just posted on the other topic)

 

This post was modified 8 months ago by Demon85

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zorpiedoman
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All prints since my one successful print have failed. I can't take it any more. I gotta find a better printer.


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3nderUser
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Posted by: @demon85

Second, is that normal that after every print I have to readjust the leveling? When the print is finished I often check the leveling on the home position out of curiosity, and the paper either moves freely or can't even push it under.. I heard that others don't even touch leveling for months, so it's a bit frustrating.

The adjusting knobs under the bed seems to have the tendency to loosen themselves. Some people use the stiffer yellow upgrade springs under the bed so the knobs don't come loose so easy.
You could print these parts: Ender 3/Pro Bed Level Locks wich locks the knobs so they hold their position.

But best solution is to order a BLTouch (or cheaper 3DTouch wich works also fine)
Then you can hit the "print" button and walk away without any worries about leveling. The printer checks the bed by itself and adjusts for the right printing hight.
Only have to set the z-offset once, depending on the mounting hight of your BLTouch.


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Eli liu
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@zorpiedoman I will not repeat what others said above. Those are great tips. From the pics, I find the extruded lines are thin and "weak". The nozzle/tube may be jammed and couldn't squeeze 0.4mm strings, which is the main reason for no stickiness. Watch the nozzle cleaning tutorials and replace a new nozzle, Make sure the come-out PLA is thick. Use Raft in Cura for more bed stickiness


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3nderUser
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Thin lines can also be the result of under extrusion.. Did you callibrate your extruder? Thus when asking 10cm the printer really extrudes 10cm. 

Ender 3 V2 Estep Calibration [Step-by-step guide]

And make sure your printer settings in the slicer are correct for the size of your nozzle. If in slicer nozzle is 0.3mm but on your printer is 0.4mm then also get under extrusion.

 


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bigheph
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what is your initial layer height and normal layer height?

 

You may have more success with thicker layers while you are still getting the hang of things.


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bigheph
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might also be worth going back and checking your build. frame check, screw check, etc,

 

https://teachingtechyt.github.io/calibration.html#firstlayer

https://all3dp.com/2/ender-3-calibration-how-to-calibrate-your-ender-3/

all links good for reference

 

This post was modified 8 months ago by bigheph

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zorpiedoman
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Wow, the outpouring of support really helps. Thank you. Today I will painstakingly document everything I do and log the results with descriptions and pictures. Here we go...

> I just took the glass bed off and washed it with soap and water. Rinced well, and set it in the dish rack to dry.
> I came back to the printer and (1) mad sure it was square to the table and sitting flat and (b) measured the x-axis beam to verify it is within 1mm of square. It is.
> I checked the tension on the belt for the bed motor (y-axis?) at the mid point I can pull it up about half a centemeter withouth much efford. Seems about right.
> I checked the tension on the beld for the print head (x-axis?) It is the same as the bed belt. Seems good.
> The bed and the print head both move smoothly along their tracks with little effort.
> I did not want to disassemble the tower to check the wheels because it took me so long to the this thing square, but on my last tune-up they ran were smooth and rolling easy without any wiggling.
* The x-axis bar is very easy to push in the downward direction but takes considerable effort to push it in the upward direction, but this is how it has always been. The printer is turned off.
> I turned the printer on to heat up the nozzle. As usual the fan whines loudly for about 30 seconds. It shouldn't do this, but I guess it is a common issue and it quiets down once it has be on for a bit.
> After the nozzle was heated up, I pulled out the filament and cleaned it out with the needle. I also did a visual check to make sure there was no material stuck to the exterior of the nozzle.
> I re-inserted the filament and ran a bunch through to insure smooth flow.

I believe this verifies the printer itself is set up properly. I'm going to go watch a video now then come back and report on my bed leveling process. Stay tuned.

-John


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zorpiedoman
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Ok, I'm back. I had some breakfast and watched a video on how to calibrate the extruder.

> I measured 100mm and 110mm on my filiment and marked both spots.

> I heated the nozzle to 200 degrees, then set my extruder to 100 and let her rip. 

> First round it under extruded by 9mm. Second round it under extruded by 7mm. I took the average of 8mm and did my math. 93x100=9300. 9300/92 = 101.1. I set the Transmission ration E to 101.1 and saved my settings to the SD card.

So now I have to remember to alwas boot the printer with this SD card inserted or the settings are lost. (Or I leave a stick note with all the custom settings and set them manually, I guess.)

Now on to bed leveling:

> I heated the nozzle to 200 and the bed to 70. I found that these both expand when heated from earlier leveling procedures. SHOULD I BE DOING THIS COLD OR HOT?

> When I first started to slide my paper under the nozzle, I noticed there was some material left over on the nozzle from the calibration. This time i cleaned it and also backed the filament up a notch so no more would ooze out on its own. 

> I did the "paper" calibration for the height. All four corners tested three times for just a slight bit of resistance. Went to the center of the bed and it felt the same. Feels good.

TIME TO PRINT...

> I am first going to print a simple cube. This was one of the objects that I had one successful print with a couple days ago. I will video the process.

> The test line looked better than ever. No blob at the start, nice consistant flow and when it lifted up to go to the center there was not a thin fiber of material getting dragged to the middle which had been happening before. All my settings are standard for this. Temp is 200/60, 0.2mm layer size and no adjustements for first layer.

PRINTING RESULTS:

> There were no issues with bed adhesion this time. Both the test line and the cube stuck just fine. This is a huge step forward.

> The cube itself was not perfect on the first layer. The edges were not sharp and crisp, rather rounded and extruded a bit. This MAY be due to an over-extrusion setting on the first layer. I'm not sure. I'm not 100% sure of what all the settings were when I saved the .stl file in cura.

So this is good. On to print test #2...

>This object is way more complex with more highly configured with first layer settings. The first layer is thicker (.28) and printed very slowly (10mm) with 120% extrusion. This is because of what I'm printing. I have a gap I need filled ever so slightly.

> This was a disaster. The was a long fiber that was dragged all the way from the test line to the center. There was a blob (still attached to this fiber.) Some of the base was sticking, some if it pulled up. I stopped the print immediately. See attached picture.

To be continued...

 


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zorpiedoman
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UG....

So after my mostly successful print of the cube, I have made three attempts at printing something else... all have failed as before. blobs, dragging fibers of filiment, no bed adheasion.

WTF????

Do I have to spend 2 hours recleaning and recalibrating my printer EVERY SINGLE TIME I PRINT?????

I even just tried to print the cube again... you know, the one that printed fine an hour ago after I went through and re-checked everything?

The material just gooped up on the end of the nozzle with nothing sticking to the bed at all.

ARRRRRRRGGGGGHHHHH!!!!!!


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zorpiedoman
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The blob... (ATTACHED)


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