Tiny, Cheap 3D Printer Working!

My ultra-inexpensive 101Hero 3D printer arrived about a month ago with a bad motor.  Fortunately, another owner had started a group-buy for better replacement motors, which I joined, and which had arrived just before the printer.  I replaced the bad motor, though I had to swap the pink and orange wires in the connector to get it to rotate in the right direction.  I probably should replace them all, but I want to see how long the other two original motors will last.

I covered the build plate with the horrible yellow masking tape that came with the printer, because the blue tape I had was dried out and I didn't want to wait to get more.

I set up Cura using the 101Hero config file provided by the manufacturer.

Next, I followed the abundant setup advice on the 101Hero User Forum (the site is independent of the 101Hero manufacturer).

I added rubber bands to the arms to reduce the looseness/shakiness of the print carriage.  The arms are so flexible that putting the rubber bands in the middle caused bending (which would throw off the geometry), so I put them up near the top of each arm pair.  The rubber band tension was as low as I could get it and still have them stay in place.

I did a few 1-3 layer prints to calibrate the printer (and use up some of the questionable white filament that came with it).

Despite the print bed being level and at the right height, I still had adhesion issues, so I made the first layer 50% thicker (rather than do a brim or raft).

I then switched to this inexpensive PLA filament from Amazon because I could get it delivered the same day for free (via Amazon Prime).  It came well packaged, including a zip-lock storage bag.

Then I tried my first "real" print, a tiny phone stand.  The print is completely functional, but is far from perfect.

I saved the GCode, primed the extruder until the new color came out, then started the print.  I waited four long hours, hovering over the machine like a husband during a delivery.

The resulting print was strong (good layer adhesion), but does have issues.  Here's what it looks like:

  

   


Here's what I observed, and what I think it means.

• Not in photo: The skirt (the outline printed around the part to prime the extruder) was almost completely missing, and the little bit that was there was thread-thin.  This happened despite priming the extruder moments before starting the print.  Extrusion rate too low?  Blocked extruder nozzle?
• Print is fuzzy. I removed most of the fuzz prior to taking the photos, but some is still visible in the interior.  Too little retraction?  Temperature too high?
• Bottom has a combination of adhesion failure and Elephant's Foot.  Easy: I screwed up the calibration.  And I really should get some blue tape.  Any other factors?
• Fill isn't tightly joined to outer wall.  Under-extrusion?  Need to increase fill overlap?
• One layer about 1/4" from the start is totally squished.  Easy: I bumped the printer, hard.
• About halfway up the whole print steps over a bit.  I didn't have a spool stand and the filament was getting pulled tighter and tighter.  This is when I moved the spool onto a stick.  Any other possible factors?
• There are small "waves" crossing multiple layers in the later half of the print.  My guess is I still have filament tension problems that will be fixed by getting a real spool holder.  Are there other causes?

Those are all the defects I see (as a 3D printing newbie).  Are there more?  Are the photos good enough to tell?

I then put Blue Tape on the print bed and rigged an emergency spool holder using a paint roller (which works awesomely):

Print quality immediately improved to an amazing degree.  I then printed the other stand included in the above link (visible above), and then printed a Star Trek TNG communicator badge (which was printing when I took the above photo).  Here's a close-up of it:

The upper surface is a bit rough, but that's no surprise given the 0.18 mm layer thickness.  I may try it again at 0.10.

My next plan is to do some prints for dimensional (geometry) calibration and for temperature calibration (should be done for each filament spool).