Printing Without Raft

[mrc93]

I am hoping you guys can help me.

I have been printing on my M2 using Simplify3D for a while now, but I have always used a raft and supports, after lifting my model up 1mm. I wanted to to try printing directly onto the heated bed without a raft and it will not print.

My hot end is not jammed, if I click add raft there is no problem with laying down the first level, but without raft no plastic is put onto the bed and just wraps around the hot end. I just printed the bracelet sample part directly from gcode that MakerGear has on the wiki and that printed fine as well.

Is there something I need to change in Simplify3D or something else I am doing wrong?

Thank you

[insta]

ABS or PLA?

The filament coming out and not sticking to the bed tells me you're slightly too high off the bed. The raft would fix that because it extrudes additional plastic which is apparently enough to close the gap.

With the hotend and bed at temp, you should have an ever so slight drag on your nozzle against a sheet of paper laid against the bed. If it moves freely, adjust the Z screw and re-home Z. Repeat this process until the paper just drags but you can still push it under the nozzle without buckling.

[mrc93]

Thanks for the quick reply. I am building with PLA.

So far I have leveled the bed, I have moved it up once printing has started using the z-axis a couple of times. I have also changed the gcode z-axis offset a little. I think it is something in Simplify3D as printing straight gcode, the bracelet, from http://makergear.wikidot.com/m2-sample-prints works fine.

[jimc]

Zip up an fff or factory file and post it

[mrc93]

I have attached the file I am currently testing.
Thanks

[jsc]

One cause of why the stock gcode might work while yours doesn't is that you are printing at 0.1mm layer heights. That requires a good deal more precision in getting the first layer height set correctly. I agree that your bed zero is probably too far away. A quick fix would be to try setting First Layer Height to 50%. (Surprisingly, that doesn't set the physical first layer height to 50%, but keeps the height at 100% while extruding at 200%). A better fix would be to bring your bed up just a touch, and maybe try glue stick.

[mrc93]

So I re-leveled the bed twice so that the nozzle was dragging on the sticky note at each corner.
Then I tried printing with the First Layer Height at 90% and 50%. It appears as if the extruder is not putting out enough filament.

Is it just not feasible to be printing directly on the bed with .1mm resolution?

Thanks

[jsc]

No, I do it all the time.

The glass isn't perfectly flat, so just testing the corners isn't sufficient. Test the center, too , which may be domed up or down.

[mrc93]

Thank you. I think that is it. I just started printing a small cube basically on the edge and it is working.

[jimc]

watch this video. its for hyrel printers but it gives a great explanation and video segment on z height and what the filament looks like when your too far, too close and just right.

https://www.youtube.com/watch?v=Fg9omXlYR-Q