Snapmaker A250 - 3D Printing: Issues with Print Quality

Hi community,
I am new to 3D printing. Using an A250 Snapmaker with Cura. I found that my printed parts have a very rough texture. I have seen prints from the same printer with much finer quality. I have attached some pics. I would love if someone could guide what settings to change.

As of now, I have tried changing layer length, print speed, nozzle temperature, bed temperature. Of all these, only print speed produced a noticeable quality difference. Quality was much improved when i ran the printer at maximum speed i.e. 500%. But I am afraid of damaging the motors with continuous use at high speeds.

Also, when the printed is printing the skirt, or brim, it doesnā€™t extrude the filament continuously. As can be seen in the pics, it only extrudes for like half the time.
Any help is appreciated.



Used temperature, used filament, used extruder (dual, mono?), calibration, auto or manual? Used thickness per layer, ā€¦ Bed temperature? Enclosure or not? Temperature enclosure or room. There are many parameters that must be correct.

Extruder E-steps controlled?

Thank you.
Filament: I am using Hatchbox PLA. Box says temp range is 180-210. I am using 190 degrees.

Bed temperature: the parts in picture were printed at 60 degrees. But I have tried different bed temperatures (even 0) to no noticeable effect.

Extruder is mono. Calibration is already done since someone else was using the printer before me, but I did perform the paper calibration as written in the Snapmaker manual.

Layer thickness: These parts were printed at 0.24mm (rough quality for Cura). But I have tried all the variations (0.24,0.16,0.08, 0.04) to no noticeable effect.

Enclosure: Do you mean the filament enclosure? I have wrapped it in the plastic bag it came in and poked a hole for the filament to pass through. There is a desipak inside. But I doubt this setup works since some inches of length of the filament is in the open.
The printer is located in a big room (~800 sqft).

Extruder E-steps: I donā€™t know about this, but I doubt it is a problem since the parts are printing correctly, with correct dimensions. Only the surface finish is very rough compared to the earlier prints by someone else.

I have uploaded pictures. There is a pic of a cube I printed. You will notice it has a rough finish and a fine finish. It was printed at 190 degrees nozzle temperature, 20 degrees (basically zero) bed temperature. The rough finish is when it was printing at 100% speed. The fine finish is when I changed the speed midprint to 500%.
I hope this helps in diagnosis.



This is what I mean with enclosure. Room temperatures below 20Ā°C isnā€™t the best. I take my enclosure temperature between 22Ā°C and 30Ā°C.

Filament temperature, I use filament from 123-3D.nl @ 210Ā°C some colours @215Ā°C. Try to print with 5Ā°C difference.

Bed temperature 60Ā°C. After a few layers I set down to 40Ā°C or less.

X axis 200mm/s. Y axis 150mm/s.

First layer 0,3mm all the other 0,15mm.

4 closed layers on bottom and top.

Wall thickness 3 prints.

E-steps read this.

For the ā€˜paperā€™ calibration, with 70Ā°C heated bed, I take a value 0,05mm lower then the SM card is given.

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Thank you. Iā€™ll try out these changes.

Typical printspot is the center of the bed.
Your nozzle on the first layer is too near to the bed. The squeeze on the first layer causes squeeze on the next layers, like overextrusion.

Try a higher z-offset or center of the bed and check again.

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Yes. The nozzle starts from that corner before going to the print coordinates. It leaves a trail of liquid filament, dirtying the bed. So thatā€™s why i just moved the coordinates to that corner so the bed doesnā€™t get dirty. Otherwise i have to cover the whole bed with tape.

Iā€™ll try some higher offsets.

Which calibration? And do you mean they finished their print and then you did yours?? Or was it moved between jobs?

You could be dealing with more than one problem, there is clearly a levelling problem when itā€™s printed in the corner, I would put it back in the middle and deal with one problem at a time. The print looks too shiney and therefore possibly too hot, especially if itā€™s leaving ā€œa trail of liquid filamentā€.
I see no benefit in putting the spool in a bag for the relatively short time of its use. Are you really sure it is feeding smoothly? Are you sure it doesnā€™t get caught for a moment when you are not there? Also, you should feed the filament off the top of the spool, not the bottom, it will enter the head at a better angle then.

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I just put it because i read that moisture affects the filament. And saw a video in which they had placed their filaments in a plastic box. So tried to emulate that.

Regarding feeding, sometimes the filament does become rather tight, but i thought that the printer would give an error if it didnā€™t get the required amount of filament. Sure, Iā€™ll put it from the top, thanks.

I also think that its too hot, but when i tried printing at 180 (minimum for this filament) it was depositing a lot of material at the end of each layer. I donā€™t know why it did that. but my cubes which i printed to check the print turned out distorted.

The reason i think it is hot is because there was this print in which after some bottom layers it had more travel time in the top layers due to the geometry, and the print was much fine (better finish) there because the nozzle was taking more time to reach each end of the print.

UPDATE: layer thickness is showing some difference now when i print some bigger dimension prints.

And the calibration question?

There is only a filament run-out sensor, it doesnā€™t know how much filament it is actually feeding, only what it thinks itā€™s feeding. Getting the two things to agree is the E-step calibration.
I donā€™t know if the filament-feed motor has some kind of overload sensor if it is struggling (current draw?). I think not as some have shown photos of the filament being worn away in one spot when the filament is jammed.

Oh yeah sorry. So I donā€™t know what he was referring to by manual or auto calibration. I just said it is already calibrated because the parts are printing fine. So like the printer was setup and assembled by someone else. I am just using it now. I did do the paper calibration though. That was at the center of bed, as you said.

But it did the bed levelling check first, all around the bed?

yes. it checked 9 or 15 points around the bed, then asked to check z offset in center by paper.

Most people would say use the 5x5 (25 points) levelling and with the bed preheated.

Sure, Iā€™ll do that.

Hi,

Iā€™m also new in 3D printing, already printed successfully objects with A350T with an enclosure (which means an enclosure like buckfast_beekeeper has shown in the first link).
As my device is in a room in my cellar which has around 15Ā°C temperature it is good to have the enclosure as it really keeps the device warm inside. That much warm that I doubted that it maybe could be too much. So I open the first part of the door a bit so that the air gets not warmer than around 24Ā°C (with closed door I would say itā€™s around 30Ā°C) - all temperature values here are only estimated, not measured.

I use Luban which provides a lot of default settings which seems to be good. So I only adjusted if I use a brim or not or if I print fast or slow and so on, so only some very basic values. The printer itself says it prints with 205Ā°C and a bed temperature of 70Ā°C and it doesnā€™t start until it reaches these values. I was printing with 40mm speed and 0.2mm lines.
I printed a dice tower model with it which printed a bit more than 3 days continously without break with the black filament shipped with the printer. A model without any support.
There was really no problem, it printed perfectly.

When I bought some additional filament (6 roles with 250g for 50ā‚¬) I had with similar settings also perfect results. Except that it also left an unwanted small filament trail when it started at the corner (but then printed anything normally in the center of the bed). In opposite to the shipped filament I saw from time to time a jerk where the whole module was vibrating a bit with a not so nice sound, where I didnā€™t find the reason when watching the device.
I found it a bit later: The filament spool had a bit of the filament looking out of the inner ring, surely for fixing it when the filament was produced. But as the filament spool only ā€œhangsā€ on the axis and not rolling over it like with a ball bearing in the middle it just disturbed the module to get the filament and whenever the filament in the middle reached the axis it ā€œjumpsā€ over the axis producing that problem.
So when I see your bag around the filament spool I would say this will probably produce similar problems, too. The spool needs to hang freely over the axis so it can move forward very easy, then the print process is smooth. When people using a dry box I think they make sure that the filament also runs smoothly out of the box.

My solution here was simple: I used the wire cutter which was also delivered with the device and cutted the end of the filament inside the inner part of the spool so it again runs smoothely and the problem was gone.

Maybe worth a look inside the spool and also removing the plastic bag.

Have fun!

Thanks for sharing. I removed the bag. And made it feed from the top. Can you share pictures of your model? I want to see the surface finish.

I donā€™t have the model anymore as it was a present for my mother, but you can find it here:
https://www.printables.com/de/model/851935-dice-tower-castle-stairs/comments/1825275

I used a bit sanding on the surface to remove the shiny gloss and let it look like bricks, but when you zoom in you can find the original surface at the lowest stair where I have not sanded it.

Thanks. I recalibrated the z-offset and found that it was indeed too close to the bed. Now I am able to remove the print smoothly and the bottom layer is also very smooth now. Came back to update regarding this.

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