First Print! X-axis issue? Any ideas?
Assembled my first 3D printer and printed this little cactus form (about 80mm in height)!
It seems that on the X axis I'm getting some occasional layer shifting? It comes and goes up the form though. The bottom is bad, middle is passable, then it gets bad then passable again.
Any ideas of what I should tweak on the machine? The belt tension seems OK (by my judgement anyways).
Thanks!!
toby
Re: First Print! X-axis issue? Any ideas?
You might try printing the cactus without rafts or supports and see how that goes.
As for X-axis variance:
1) Have you looked at the belt tension numbers with the display? 240 +/-40 is the manual guideline. I find the numbers unreliable, but they are a good place to start. X and Y values should be similar. Also, when you "pluck" the belts, both axis should sound the same.
2) Does the X-Axis move freely when you slide it side to side, power off? It should move easily without "sticking" along the way. Same for the bed Y-Axis motion.
3) Belt tension is best measured with a scale. A fish scale or trigger scale work. With extruder fully left, and bed fully back, the bottom belts should deflect up about 3/8 inch with 2 pounds of vertical pull. If the bottom belts can deflect and touch the top belts with 2 pounds, the belts are a bit loose. But keep in mind the difference between too loose and damaged motors is a fine line. The other method for gauging belt tension is the frequency method. Belt tension seems to be an arcane art form - but there are a few threads on the subject.
https://shop.prusa3d.com/forum/general-discussion-announcements-and-releases-f69/how-exactly-to-increase-tension-on-x-and-y-belts--t26094.html#p121136
Re: First Print! X-axis issue? Any ideas?
is your motor pulley installed correctly, one grub screw firmly tightened against te centre of the flat on the motor spindle the other firm against the shaft?
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: First Print! X-axis issue? Any ideas?
Joan brings up a good point: a loose drive gear might explain the dither.
Set screws must be tightened in the right order or they'll come loose:
1) Loosen both set screws.
2) Set the screw on the flat, ensure it's aligned perpendicular and mid-flat, tighten.
3) Set the offset screw, tighten.
Note: Be sure the Allen wrench is fully inserted into the screw or it can strip the socket. Set screw or grub screw - the terms come from different planets, ymmv. I personally don't think they look like grubs, but some folk do.
Re: First Print! X-axis issue? Any ideas?
Joan totally called it. I thought the set screw was sufficiently tight but it turned out it wasn't and would occasionally slip on the X.
tim.m30, when I was checking my belt tensions they registered quite a bit higher at 271 and 273. It seems to be running perfectly fine though. Should I loosen the tension a bit?
Re: First Print! X-axis issue? Any ideas?
The belt numbers are fine; at best they are "in-the-ballpark" quality numbers. A tension gauge is the only way to know what the real belt tension is.
btw; I've played with belt tension from too loose (sagging) to way too tight (guitar pitched strumming) and my numbers are 280 +/- 10 over that entire range. They tell you more about the alignment of the bearings and rods than the belt, but they should be close to each other.
Re: First Print! X-axis issue? Any ideas?
Nice!
I appreciate all the help everyone.
-toby