Bukobot 3D Printer Forum
Bukobot Assembly Discussion => Hardware & Mechanics => Topic started by: Hippo on February 03, 2014, 06:37:13 AM
On my duo, the height of the two nozzles doesn't match. Extruder 2 is about .2mm lower than extruder 1, and will sometimes bump or scrape the active layer when passing over material printed by the other extruder.
How do I adjust the heights so they match?
I had the same problem with mine. I fixed it by simply loosening the black screw that holds the extruder assemble down and sliding some paper shims underneath the low one. This assumes you already have your bed setup.
That's great. I was so obsessed with the idea of moving the threaded part that I didn't even consider moving the entire assembly.
They should all be within a tolerance of .02mm. The only time we've seen a variance that big was on a machine built with one bad bearing (the bearing worked fine, but the grooves were out of position so that the carriage plate didn't sit properly on it, and we've since redesigned that piece to be more tolerant of these issues). We discovered that the carriage was not sitting flat by removing the extruders, standing a machinist's square on the Y beam (with the platform all the way back), and watching how the height of the square compared to the top of the carriage plate as it moved back and forth.
Regardless, our recommended fix for this type of issue is, as midoco did, to loosen the mounting screw of the extruder that sits lower and shim it to match the height of the other.
Wish I'd found this earlier..musta missed it. I adjusted the threaded bit...but knowing the paper thing will help me to get them correct.
2nd Extruder is RUINING my prints!
No matter how closely I have the two extruders aligned vertically, the 2nd still scrapes across the existing material either creating "ghosts" of the nearby geometry in the currently printing area, or just piain pulling the print up off the bed.
The 2nd head either ruins the part finish, or ruins the entire print.
Is anyone getting dual extruders to prints smoothly????
I sometimes get the ghosting, but it usually goes away after a few layers.
Have you measured the filament diameter along several points with good calipers and entered that in to slicer? You might me putting out too much material.
Try dropping your bed just a bit to give the first layer more room.
Hope this helps,