Difficult to remove prints

After researching the problem I learned that Snapmaker’s calibration instructions SUCK!

You have us set the z axis with your calibration sheet, and it ends up being way too tight to the print bed.

After hours of searching and reading, I raised the z axis so there is BARELY (not enough to cause it to bend when you push it) any drag on the plastic test strip they provide when you pull it. After that I finally got my 6th print attempt to be mostly successful. There was a lot of stringing. It had a solid square base, so it was easy to remove.

So I then made the following changes after reading more:
Lowered nozzle temp to 195
Decreased flow to 95%

Then I printed a glider. And just like before, I have to practically destroy the print sheet trying to remove parts of the print.

I don’t need better adhesion to the bed, yet adhesion within the prints themselves is weak.

Coming from an IT, tinkering and electrical background, I am thus far not impressed.

Why is the provided filament sticking like glue to the print bed?

image

Thanks for the picture, that’s crazy stuck. I haven’t had anything like that happen. All my prints have come off with little effort.

Only thing that comes to mind at the moment is make sure it’s cooled down to room temp before removing, as it cools the plastic will contract, which should make it easier to detach. You could also put it in the fridge.

I prefer to work a small tool around the entire perimeter and working towards the center.

All of the other ‘standard’ tips are things you’ve already tried - z height, temp, flow. The bed looks clean and undamaged. Assuming there’s not a filament issue, but that can happen.

The way I set z-height is similar to what it says in the manual - calibration card (or paper) can be removed and slid back under the nozzle, but pushing with a fold (or ‘wave’ in the card) will not straighten. If it’s too low you can’t slide the card back under the nozzle, and if it’s too high you can’t keep a fold while pushing - it will always straighten.

The one good print I had was put in the freezer for ten minutes. It was an item to fix a different issue; the filament dragging on the tower. Based on its shape, it would have been easy to remove without the freezer.

The glider cooled overnight in my living room. It’s so thin at the wings, I figured the PLA would be too brittle to scrape off without damaging it.

I have the z-height adjusted so high that if I raise it .05 it not longer has resistance at all.

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Well I’m afraid I don’t have much other experience with this - although I think several other people on this forum have had similar issues. Maybe they’ll reply, or you might be able to track down some of their other threads on this topic.

Have you tried printing with a raft? My “limited” experience with printing relatively fragile D&D miniatures is that going into the build plate adhesion setting and choosing raft gave me a nice surface that I could peel off the build plate without doing damage to the model and the raft was easy enough to remove from the print.

I tried a grasshopper with a raft. It was a disaster, but I’ve also changed other settings since that attempt.

I will definitely try the raft for other models, but I’m pretty sure printing the thin wings of the glider on a raft would be impossible to remove from the raft. Wouldn’t it just result in the wings being as thick as the raft+wings?

Just got some non-Snap Maker filaments delivered today. Will try some ABS, polycarbonate CF, and CF infused PLA and compare results.

Can’t say for certain, but my experience has been that removing models from the raft is much easier on the model that using the scraper to remove the model from the bed, if for not other reason than you can more selectively apply pressure to peel the raft off once you have everything removed from the printer.

Have you read this thread:
3D prints stick WAY too well!

Thanks for the link, Atom. I read through it. Before reading it, I had already made some additional tweaks AND changed my filament to Proto Pasta carbon fiber infused PLA. Night and day difference! So I would say the filament is a big part of the issue. The black PLA that came with my Snap Maker wasn’t that great, but I printed with it first and got semi-ok results. The white PLA from Snapmaker was far worse and sticks like glue.

The Proto Pasta produces a perfect and beautiful print. I was actually amazed at how smooth and perfect it came out. I’ll add a picture when I get home.

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If your still having issues with adhesion let us know… maybe posting your slicing settings and a good pick of your first layer… those would help us determine possible issues. I look forward to seeing an intact glider :wink:

Happy making
-Atom

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Someone explain to me why a raft sticks to the print bed just fine, but an actual part without a raft will not stick. I’ve tried hairspray and countless settings changes. Even f it starts to stick, it lets go repeatedly soon after. Sloooooowwwww print speed, hot bed+hairspray, fat and tall first layer.

About to throw this out the window. Makes zero sense a raft sticks no problem but not the desired part. I don’t want a raft, it degrades print quality on the bottom.

What filament are you using and what is your nozzel/bed temps?

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In addition to what Atom asked, double check your Z heights. Those first layer extrusions aren’t fused together, Z looks too high to me.

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The z height is set that high because removal was impossible with it set lower.

I still don’t se why a raft stays in place, but a part with no raft gets smeared all over the print head and drags everything around. The raft has to stick to stay in place.

Nozzle temps ranged from 195-220 in increments of 5. Bed temp from 40-70, same increments. Using Proto Pasta CF. Will try a lower z height, the major sticking problem was with the Snapmaker provided PLA.

Could have to do with print speeds - at least my slicer prints rafts twice as fast as out perimeters. Maybe there’s more or less drag / heat on the filament for one motion vs another.

I also have this problem. I used a raft and it can be removed easily but the first few layers looks terrible.

Previously with Makerbots I’ve used blue painters tape on the build plate.

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A recalibration of z height, while print bed is hot to account for expansion, resulted in a nice gouged trail. Other side is already destroyed from the white PLA adhesion issue.

image

:frowning:

If it helps you get some more life out of that bed, just know that I have a few scratches and gouges in the bed - I take a file to the bottom of prints at the end and it’s never been a functional issue.

That sucks though, sorry to see that.

you can probably still use the other side as well… this is the bed i use with my ender 3 and i have no issues:

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You are correct, all of the calibration instructions are severely lacking, and some are incorrect as you noted. I am planning on creating a real calibration guide, but I don’t have much time outside of work, so it may be a while before I can make one available. To help you out now, here are some things that you need to do:

  1. Only run calibration while the heat bed and the nozzle are up to temp. This can only be done if you have your computer connected to the Snapmaker. Both WiFi and USB will work, but USB is easier to setup and there are issues with WiFi. If you disconnect from WiFi while printing, the print will abort.
  2. The correct Z offset after calibration is just as you noted, where you can feel the nozzle touching the card, but it moves freely. Any kind of binding is too close.
  3. You need to calibrate the extruder. The default settings will severely under extrude, if you don’t calibrate it. I don’t have a link available, but there are instructions from other users on how to do this. Make sure you test with a 100mm (10cm) length. Don’t forget to save the settings after calibration, or they will be lost after a power down or reset.
  4. This is the most important, if you want good layer adhesion. DON’T USE LUBAN. Luban is fine for talking to the printer, and it might work well for CNC and Laser, but as a slicer it is really bad. I’m using [Ultimaker] Cura (which can be downloaded for free from Ultimaker), and have not had a single failed print since. You will need to do a lot of setup, especially configuring it for the Snapmaker, but it will pay off in the end.

I hope this helps steer you in the right direction. Best of luck!

P.S. I have an A350, so I changed the calibration grid to 5x5. The larger, the better, and the less chance you run into leveling issues.

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