MakerGear Forum

Hi, everyone. I'm new to this forum (Used to be on Google groups but went inactive) but have been a long time proud owner of a M2. I use S3D to drive my M2 and have had no problems with it.

The issue I'm having is that my M2 creates an uneven surface on the first layer - where if you were to look at the object in the front, you'd see multiple bumps when the M2 is creating the first layer infill. When these bumps are created and the M2 has to move across the surface to fill in other details of the object, the nozzle runs into these bumps and vibrates the machine as it's traveling. I don't think this is good at all to run the machine like that, so I stopped the project and decided to post my inquiry here. What's interesting about this situation is that smaller objects (about under 30 mm in length and width) print out nice and there's no imperfections in the first layer. I checked my bed to make sure that it's set properly to the nozzle, and it was. I dialed down the extrusion speed to see if the extruder was over-extruding and perhaps was making these bumps. However, the problem still persists. I tried speeding and slowing down the first layer, but the magic bumps appear regardless. Changing the bed temperature has no effect, either.

I then tried to dial the first layer height down to 50% to see if it would apply more pressure to the PLA being extruded onto the bed, but the bumps are persistent. I dialed the first layer height up, but adhesion problems and the bumps messed up the print. I've attempted these settings vice-versa but the problem still persists.

Any help is very much appreciated!

Could be a couple of things causing it - if the bumps are uniform across the print, it's probably that your Z-stop is set too close to the nozzle and you are overextruding. Run a calibration using Jin's description here: viewtopic.php?f=3&t=1964

You can make some minor adjustments to the G-code in S3d to take care of small variations for different filaments (what you are seeing) without having to reset your Z-stop, but you should run a calibration for each spool, because they each extrude differently. (The link in Jin's write-up.)

Or, if you're printing from the same spool and it never caused the problem before, your bed might have gotten out of level, and you might want to run through the leveling procedure.

Hi, Jules,

Thanks for your quick reply.

I printed off the calibration tester with no bumps and the final print turned out to be nice. I calibrated the bed again to make sure that it wasn't the cause of the annoying bumps. I ran the original print with the settings I used on the smaller calibration test (Minus the 0% infill and 0 perimeters) and the bumps still persist.

Greetings, everyone.

I just bumped my first layer height percentage upwards and that seems to have fixed the problem! I watched the print and saw that the nozzle was pushing filament in the direction of it's travel (As though it was pushing melted filament across) and that was what was causing the problem. Now it's printing without any trouble.

Thanks for your help!

Yeah your bed is too close to the nozzle. Adjust it on the printer not in s3d. Kepp layer height and width at 100% while ypu set that and tune it in.