Random crashes on Y axis?
So I started having lots of crashes detected on the Y axis for no apparent reason, most of them in the same rough spot. Looking at the print, there is nothing to really catch on, it's the first layer and all. I stop the print, check the Y axis by disabling the steppers and moving it back and forth with my hand... Seems smooth? I do a quick search and find two camps, one larger camp that just disables crash detection and one slightly smaller camp that insists that something is wrong with the printer if it keeps doing that and you should never disable it because it's there for a reason.
But it's late and I try my luck with disabling it and start printing. I wake up this morning and see it printing nicely with neither layer shifts nor PETG strings caused by rehoming. It really doesn't seem to me that there's anything wrong mechanicallly with my printer. So which way is it? 🙂
RE: Random crashes on Y axis?
Take a video. Contact support via chat. They will ask for the video during the chat. Mine was due to belt tension.
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Chuck H
3D Printer Review Blog
RE: Random crashes on Y axis?
@charles-h13
Too high or too low?
RE: Random crashes on Y axis?
The goal was 200-280. The middle is the sweet spot. I was too high but I have seen it happen with both.
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Chuck H
3D Printer Review Blog
RE: Random crashes on Y axis?
@charles-h13
Meaning "too tight" or meaning "too high number"?
RE: Random crashes on Y axis?
Two low of a number and too tight.
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Chuck H
3D Printer Review Blog
RE: Random crashes on Y axis?
There is a known bug in the firmware. It seems related to filament sensor. Try disabling the filament sensor, see if it has any effect.
Second is U-bolts can be overtightened very easily because a quarter turn of the nylock nuts can mean the difference between too loose and too tight. Loosen the nylock nuts until the bearing wiggles, then tighten until the bearing just stops wiggling; that is plenty of tension. Any more tension and the bearing case deforms (bearings are designed that way).
A crash is simply when the motor controllers detect an overcurrent. This means friction is too high. This friction induced current is what the LCD reports for belt tension. Belt tension - unless waaay too high doesn't affect friction, so never shows up in the numbers. Belt tension must be measured if you want to set it accurately.
ps: my belt tension is set to 6lbf, and my belt numbers are around 295. 240 is a pipedream and represents a lot of friction, and a lot of crashes.