Haven't seen this before? Only half of the print bed prints bad?

Bambu Lab X1 Series
1

Having pretty good luck on prints with my new X1. But came across this issue today.

I was printing a U shaped piece of trim using Bambu Labs grey PLA tough. One side of the plate looks good, the other bad. This is my first print that covered the whole plate so not sure if it has always been an issue or if this is new. The entire piece was still stuck to the plate. Left side didn’t seem to be floating about the plate.

I dried the filament for 8 hours at 55 c. I used the bambu slicer, default settings with the AMS. I always use the auto level, and calibrate daily.

It appears the issue goes through all the layers just for one side. I did have the lid on, will try again with it off, but seems that would cause an issue for the whole print. Maybe one side is the printer is hotter? I have the printer on a heavy table with nothing on either side.

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Anyone else seen this and got an idea how to fix?

2

It looks, like your Cold Plad was not fit excatly on the Hotbed, therfore you have Z differences

1 Like
3

It seems that the problem is on the side which is close to the auxiliary fan. Maybe try to reduce it or disable with this print.

4

I agree that the difference is probably caused by a cooling issue. Bambu recommends that the top be off and the door be open when printing PLA. If that does not help, try rotating the print so the open side of the U is on the left.

5

Thanks for suggestions. I reran the print again this morning with lid off and the auxiliary fan set to 0. Its is still happening. I set the retraction to .8 at 40 mm/s.

I got a level and found the printer was ever so slightly not level. Put thin piece of plastic under both legs to make it perfect level.

I noticed the issue goes away when I slow the printer down via silent mode. When I speed the print back up, the nozzles zips from the plate left to right causing the stringing and bumps, but not when moving from right to left across the plate. I am swapping cold plates and running a model spread across the plate to see if stays.

I post when complete.

6

Try running a bed level test, essentially a thin sheet across the entire print bed.

You might have an uneven printbed for which in the extremities, the bed levelling doesn’t adjust for.

7

Thanks all. Pretty sure it’s the cooling. Running anything close to the edge, near the fan cause stringing. So turning it off or low when I have to print something close to the left edge of the plate. I probably need to work more with other types of filament. PLA/PLA tough just normally work so well.

8

I had trouble with a print where I could not get the fan to stay off or at least at a low speed. At every color change, it would revert back to what ever the printer wanted it to be. I added a strip of blue painters tape along the fan’s outlet duct to direct the air away from the build plate. I don’t remember if I directed it up or down but it seemed to help with that print.