Had my first birdsnest today

I was printing a simple piece, basically a tube 2.250" OD and 1.75" ID x 1" tall
with a brim, 100% infill… Simple enough but 20 min. or so into the print it peeled off the bed and a family of birds could have nested in the mess. Rinse and repeat and again the same thing happened. I examined the print and it was obvious that the part had curled up off the bed on the OD. I usually print on glass and glue and this has been very successful for me. Is it the part shape or the 100% infill or ???

I may repeat this with a raft or lower infill but that is not optimal since this part needs resistance to being crushed in a lathe chuck.

Try a larger brim. Also, in Cura, at least, there is an optional “Draft Shield” setting (search for “shield” in the options settings dialogue). I found that that helps.

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What material are you using? I’ll assume it is ABS.
My personal recipe.
I use an enclosure, no extra heat, i.e. just the bed. I get around 35 degree in the enclosure.
I have good success with Magigoo on glass which provide better adhesion than glue stick.
Bed at 100 degree. Hot end at 250 (Sakata ABS).
8mm brim. Slower speed will help to minimize the warp. I use 40 mm/s normally. For some pieces I go down to 30 mm/s to help with bed adhesion. I know: it’s super slow. I print PLA close to 100 mm/s. For a cylinder like yours I print PLA at 130 mm/s with no issue. Geetech A10 with E3D V6, Extruder Voron M4.

Iwould suggest going back to basics first before all kinds of different things.

Clean off the bed of old glue or dust oils. If you use glue stick or similar clean it fully with wet cloths and then finally once clean use some IPA. If you don’t just be certain to clean the bed thoroughly.

Run a bed level calibration target to be certain the bed is good still sometimes they move. Confirm Z height.

Move the modle to a different part of the bed. try again, brim? or raft depends on the model.

You can try a draft shield but personally it wastes a lot of filament you can use lots of things to guard the printer from drafts. I’d always recommend an enclosure.

If you were not using a glue stick perhaps try some. Most will work but uhu is what I use.

Slowing the first few layers and adding a bit of bed temps also can help too.

It is PLA. I tried a raft which printed perfectly an stuck to the bed but the “part” didn’t print right again. I checked the Z offset and it was a bit high so I reset it and I’m trying another print to see if it helps. I do use glue and it usually works great.

In my experience, 100% infill seems to exert more stress on the piece, especially if the nozzle drags along the surface of each layer which can cause the piece to break away from the bed. To remedy this, I try bumping the nozzle temp up a couple degrees so the filament is more liquid as it is laid down. You could try that as well.

Although you did say there was warping at the edges which tells me the part cooled down which could indicate it was subjected to a draugh or bed temp dropped. I sometimes will bump the bed temp up 5 degrees on the second and above layers. Try that as well of your Z offset didn’t work.

I tried printing it again and got about 25% done, it printed quit nice too, when it popped off but wasn’t warped this time. After that I went back and levelled the bed and set the z offset. I also cleaned the bed and put a fresh layer of glue on it. I don’t know what else to do other then change the temp setting as suggested. I beginning to think this machine is infected with a poltergeist. I’ll try another print tomorrow.

I have a CR touch on this printer and Jyers UI version of the firmware which has a manual probe levelling option. For those that don’t have a BL kit/Jyers It moves to each of the four corners and then instead of using paper the probe tales a measurement and tells you how far of of level you are. You make an adjustment and then go to the next corner and repeat. You have to do this 2 or 3 times around the bed just like paper levelling but if you believe the measurements I have it with in 0.02mm across the bed, more in the middle, warped bed. I could have tried for less but it seemed a bit much considering how finicky the adjustments would be.

Can damp filament be a problem like this, I have heard the occasional pop???

P.S. one of the You Tube printing gurus said that instead of printing with 100% infill to limit it to 98% since 100% can cause over extrusion. Can anyone verify this???

It just occurs to me: does your printer have an Eco mode? This mode turns of the bed heat after X number of layers, but many build surfaces will let go of the print when the bed cools. If you have Eco mode, turn it OFF.

As far as I know there isn’t an Eco mode, the bed stays hot.

Yes 100% infill can cause issues on occasions. I usually use 90% maxed. With extra perimeters.

How old is the bed? The creality type surface does give up after a while. Popping off mid print sounds like something hitting it.

It could be the nozzle dragging on the infill but a few other thoughts.

Is there a cable or something hitting at the 25% height that could be snagging?

Is the print clean with no blobs or zits? Could it be over extruding and catching a blob?

Is the model flat on the bottom? Sometimes you can cut 1mm from the bottom layer (or less) and get a flat surface. Small variations can cause mayhem.

Damp filament could be but imo unlikely it usually effects print quality. You could try a different filament.

Bye-Jove I think I’ve got it!

At some point things become clear and I remembered having a similar problem once before. It is the “Z Hop” that is causing the trouble. Recently I was watching a YouTube talking head and he said to turn it off so I did and I’m am now printing the part, almost done and it has printed perfectly. It must be when the head moves up and down at some point the extruder goes a bit to low and snag’s the part and tears it off the bed. Everything else is set the same way as it was when the prints failed and the only thing different is the Z Hop being turned off.

Once again I am amazed at how good my cheap Ender3v2 prints when compared to the much more expensive “real” machines. Even using the Low Quality settings the finish is beautiful with near invisible layer lines, using 3D Printing Canada Value PLA filament, nice stuff.

Anyway problem solved, thanks for the help.

Print completed successfully, I’m back in business.

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