grNadpa

What worked: Cura 4.6.1 and hairspray on a Monoprice Select Mini 3D printer. Extruder temp 200C, initial bed temp 65C. I did check with Monoprice (my printer's manufacturer) before applying hairspray to the bed. Their response was that hairspray is okay and that printer tape is also an option. I applied the hairspray by first spraying it on a paper towel, then wiping the bed. I'm not really sure whether I need to wipe down the bed with water after each print, but that's what I've done. On a "simple random sample" of 2 prints (grin) -- one an 80 mm long wedge that tapers from 11 mm down to 2mm and the second a 40mm wide 10 mm high hexagonal object, replacing Cura 4.7.1 with Cura 4.6.1 took care of the filament clumping and the hairspray kept the base filament coating adhered to the bed.

Yeah. I am about ready to give up. I have a narrow wedge that refuses to lay down the base layer that will stick to the bed. Even when resorting to a multi-wedge object. Suspect my project will have to be crafted some other way.

@Arnookie I wouldn't have thought to install 4.6.1 without your post. Thank you. I had the same move-to-4.7.0 experience but assumed it was that my object was too small or that I had fouled my extruder. Installing 4.6.1 gave me a much cleaner result. Thank you.

@Artjom_b Nice sleuthing. I am using a 1.75mm filament (Htchbox which gets rave reviews). But, as you can imagine, I am reluctant to "upgrade" when 4.7.0 is working. I will check the 4.7.0 settings for 1.75 there as well as I still am having to abort some of my prints. Thanks for your investigative work and findings.

@GregValiant Well, call me "Beaker". No doubt your analysis is spot on, Bunsen. But I have not the literacy to follow it. However, Github tech tersely replied that they are working on a fix. And re-installing Cura 4.7.0 seems to work most of the time. Though I have not yet mastered printing a long narrow tetrahedron. P.S. Yes, I did re-slice the model. And tried other objects as well that had printed properly before the upgrade to 4.7.1. Had to abort the print on all of them.

So what is the resolution? Try to find Cura 4.6 and re-install? I, too, recently upgraded from Cura 4.6 to 4.7.1 and get the same "glop" results as @gallen99 and @Arnookie . Being absolutely new to 3D printing, I thought it was the Monoprice mini 3D printer or the Hatchbox PLA filament or the dimensions of the objects I tried to print. Never occurred to me that it could be the Cura upgrade ... ... So I tried re-printing an object that printed properly before and, sure enough, it "glopped". I had to abort the print. So is reinstall of Cura 4.6 the proper resolution (assuming I can find it) ?

@geert_2 Thanks for your detailed response. Honey and rubber bands. Don't recall working in those mediums (grin). Very helpful visuals. Thanks.

@GregValiant Truly enjoyed your comment. GM Fisher Body ... was that the branch on Willow Springs Road in Countryside, Illinois? Fortran was never my forte, but after programming an IBM 1401 and wire-boarding unit record equipment, I moved up to COBOL on a Control Data 3300 octal mainframe. Suspect you are correct on expectations for a fine model. My adventure presumes to make attachments for household appliances. I'm disappointed that the measurements don't transfer accurately, but encouraged that the inaccuracies are consistent from print to print. At least so far. So I end up wasting filament and a great deal of time fiddling the dimensions. But ultimately the objects I've printed do the job.

Terrific response. Just wanted to make sure that my skill deficiency was not the issue in this case. Thank you. Will look for "Shell". Yes, Tinkercad does provide a way to add additional "sides" to circle / cone / etc. objects. I just take the defaults, for now, as I endure the learning curve of this "new-fangled" software [being a retired Mainframe Computer applications guy that made my living in COBOL and CICS].

The object printed on my Monoprice select mini V2 printer has different diameters than my design specs. For example, when I specify an outside diameter of 21.0 mm in Tinkercad and run through Cura, the printed object diameter is 20.1 mm. When I specify 22.0 mm the objects prints as 21.3 mm as shown in the following images. I create a circular Tinkercad object of 22.00 mm (01Tinkercad.png) that I export to "vacuum connection.stl" Using an online viewer, (02GeneratedSTL.png) that shows the dimensions as I specified them. Loading into Cura 4.7.1 Prepare window (03Cura.png) shows the proper dimensions in the lower left AND (red arrow) shows that it is expecting to print using PLA filament. Upon "Save to file" in Cura, an online gcode reader also shows the proper dimensions (04GeneratedGcode.png) BUT (red arrow) shows that it is expecting to print using ABS filament. Could the PLA versus ABS be why my dimensions differ from design to printed object? If so, I gather I must change the settings that Cura uses to generate the gcode (that already shows PLA despite generating ABS). Or are my precision expectations too unrealistic? Regards, grNadpa