Prints keep getting knocked off of bed

Bambu Lab X1 Series
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My prints keep getting knocked off of the bed and I can’t figure out why. I’ve searched and searched, but I can’t find a solution.

I tried the cool plate without glue, the cool plate with glue, the high temp plate without glue, and the high temp plate with glue. I cleaned the plate with microfiber and rubbing alcohol, and then with warm water, dish soap, and a microfiber cloth. No change.

I’ve read multiple people say that grid infill can cause this. So, I tried gyroid like everyone suggested. Same exact result. I don’t think that’s the issue, though. It started with this print:

It’s hard to see, but but the support in the back was knocked off.

In this one, the prime tower was knocked down:

The infill has nothing to do with the prime tower or support, as far as I know. So, this leads me to believe that it’s not the infill.

Here are some test prints that just keep failing:

These two seem to have failed at the same exact place. Which may be a clue, but maybe just a coincidence.

This one failed pretty early:

Does anyone have any ideas? I am so confused!

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Wet filament will cause over-extrusion that can result in taller/thinner elements of the print getting knocked over. (more “pulled over” than “knocked”).

Your purge is stringy, which may mean your filament needs to be dried more.

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What bed temp are you using?

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@RocketSled All of my filament has been dried in my dryer and the room that everything is in has a humidity level below 30. I also keep a ■■■■ ton of silica gel in my AMS. How much dryer do I need to make it?

@silver118822 I’m using the default temps that Orca gives me. 35 for cool plate and 55 for high temp plate.

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Have you tried a diffrent pla yet?

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I know I have had a lot of issues with white PLA and bed adhesion in the past. Might be the pigment that is used.

Try a different color.

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@silver118822 No, but I’m about to.

@Chris1974 I’m using bambu filament. I would think that it should work, but I’m trying a different brand and color, now.

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I was just woundering if it might be defective or something, I have printed quite a few rolls of Bambu white without issue.

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@silver118822 Me, too. This is all part of a big multi print project. I’ve been using bambu filament the whole time. Maybe you’re right. Maybe it’s just a bad roll?

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Cool plate use glue, bed temp at 35

Textured PEI plate bump up the bed temp to 65

For supports I’ll hook you up with the most reliable supports I use

Normal auto
Snug
Threshold 45°
First layer density 90%
First layer expansion 2mm
On buildplate only :white_check_mark:
Remove small overhangs off
Raft layers 0
Support/raft base default
Support/raft interface default
Top Z distance 0.16mm
Bottom Z distance 0.2mm
Base pattern default
Base pattern spacing 2.5mm
Pattern angle 0°
Top interface layers 4
Bottom interface layers 4
Top interface spacing 0
Bottom interface spacing 0
Normal support expansion 0
Support/object XY distance 0.35mm
Don’t support bridges :white_check_mark:

These are my best support settings especially for less organic shapes (lots of straight lines with overhangs)

The same settings will work with tree (used for more organic models with lots of goofy angles and sharp long overhangs) but the threshold angle may need to be tweaked or switch from snug to every other type on the list EXCEPT tree strong (haven’t tested them on strong yet)

Good luck

Hope this helps, and Happy New Year everybody

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@Jrock Thanks, but this has nothing to do with support. Things are getting knocked off even if they don’t have support.

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My mistake

I thought this was a support issue where they were getting knocked off

Soooo, the prints are getting knocked off in general regardless of if you are using supports or not

What are your layer hights and line widths ?

You may simply be printing too fast on a big model not allowing the print to cool enough for the next layer

Yes, layer hight and line width also play a roll in that scenario

With larger layer hights it is good practice to slow it down a touch in order to let the layers cool diwn before the next layer

A good indication of the layers not cooling enough is when the nozzle drags while laying down the layer

You can adjust your speed settings individually or simply drop your max volumetric speed to 12 or 10 mm³/s

Increasing the layer time in the cooling section will also help, 7 seconds is a good place to be

Are these the fastest settings ?
No lol

But if you want fast settings that will park the nozzle due to skipped steps hit me up and I’ll show you the absolute limits of these printers lol

For now, I’m suggesting you slow down your walls

A quick fix is to leave all your other speeds where they are and go 125 outer walls and 275 inner walls with a max volumetric speed of 10mm³/s with a 7 second layer time

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0.4 nozzle. Layer height doesn’t seem to matter. It does it on 0.28 and 0.08 layer heights. The line widths are the defaults in Orca. The big model that failed was on 0.08 height.

While I’m not against adjusting the speed, I don’t understand why this is happening, now. I’ve printed taller things in the past (a bunch with the same settings right before this started happening) and didn’t have this issue.

I have seen people say this. Where is the setting? I can’t seem to find it.

So, I literally just had another test print finish. Same settings, different filament. Maybe it was a filament issue, but maybe it was just a fluke. Going to do more testing and see what happens.

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On the screen where your filament is selected you will see an edit tab (looks like a pen in a square beside it)

Click on that and you will open the filament settings

In the first section at the very bottom will be your max volumetric speed

In the cooling section you will find your layer time

Default is most likely set at 4, increasing the layer time will slow the print down at the threshold number once it has been reached

It seems backwards but is not, lowering the number will decrease the print cooling and increasing the number will tell the printer to slow down to give the printed layers more time to cool

For PLA leave the fans at 100% and make sure fans always on is selected

I’ve found with the latest firmware that I have had to adjust a few settings, no big deal but my previous settings were causing some quality issues

Likely because anything above 1.6 firmware is a but more finite in how it’s operating the printer

If you start having lidar issues I suggest a thorough cleaning of the extruder with the cover off using cotton swabs, lint free paper towel and isopropyl alcohol

Seems that this new firmware is a bit more sensitive

If you get the lidar message don’t simply hit ignore and resume, it throws the bed leveling off just enough to cause issues

With the added sensitivity comes possible issues with print speeds that were not an issue with previous firmware versions

But once dialed in it works fantastic and the surface quality is improved

Except for the VFA’s , I’ve been trying to eliminate that without printing too fast

The VFA’s line up exactly with the cogs on the belts and I do believe its when the belt cogs ride over the smooth idlers

Thats nitpicking though, the average person using an FDM printer isn’t using top down lighting and a magnifying glass lol

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I’ve been having a terrible time getting PLA to stick to the cool plate, even with the glue stick. I tried cooler and hotter plate heating, slowing everything down, but nothing worked. I triple washed and triple cleaned with IPA. I finally spent $ for Vision Miner Nano Polymer Adhesive. It’s keeping PLA on the plate. I hope to find a less expensive solution.

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I never could get anything to stick to the cool plate so I use the engineering plate for pla and it works great. Some time I might have to spray some aquanet hairspray one it.

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I agree - cool plate is def not good plate for PLA to stick onto, at least not at only 35 C. It may work for smaller models and short prints, but if the model is big, its gonna get knocked off the plate sooner or later. Even glue doesn’t help in my case.

What I use for PLA printing is high temp plate or other aftermarket high temp plates such as whambam, I also got one good from Kris3D. Additionally I set bed temp to 58 C and apply VisionMiner adhesive. This has worked 100% always for me and I haven’t had failed PLA print anymore, no matter how big the model is or how long the print lasted. It actually sticks so well, that even after its cooled down, I need to bend the plate to get the model off the plate.

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I personally have not been using glue on cool plates (with PLA) and have never had a single issue.

That being said, I print at 60mm/s and not 200mm/s.

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Take a look to this:

1 Like
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I was having terrible adhesion problems. The Vision Miner adhesive did the trick. Now I have a new and better solution, at least for the cool plate thus far.
I cleaned the plate, went over the printing area with a gray 3M scotch-brite pad several times and cleaned it again. Since then I haven’t had to use any glue. I clean the plate with isopropyl alcohol after each use.

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