Help, my J1 is making horrible hitting noises.
I can’t locate the hitting noises properly, but it’s not the filament rolls. (in case anyone thinks of it)
I’ve uploaded videos but it’s not easy to identify as an associated sound. In the video it sounds like someone is kicking it.
It is also not the nozzle that shoots over printed parts.
There are also no traces or clues as to where the noise is coming from.
Linear bearing, or motor I would guess…
I think it might have something to do with the temperature. after I opened the doors and the temperature dropped below 32 degrees, I can only feel it by touching the case. now that the print has finished and the case is cool and manually moving the axes, I can’t find anything.
Just to be sure: did you try to lubricate the linear rails? This reminds me of the clanking noises a damaged rail made quite some time ago in a … kind of fixture I made for our production when they did not grease it. I assumed the balls in there got stuck for a brief moment due to friction. This might be increased by thermal expansion causing increased friction in the system - I would suspect one of the rails on the sides where the print heads are not directly connected to (Y direction, I think? Still waiting for my own printer, so I cannot check)
hi, that was exactly my assumption, if only because the rails are actually very dry. Now I have lubricated all rails. Now I have to see what happens. but there is a possibility that the bearing balls are damaged, right? It was a real hit.
Okay, this tells me it is still advisable not to trust manufacturer prelubrication - good greases are expensive, so the manufacturers use as little as possible - in your case obviously not enough.
@Riskey: the J1 manual does not cover where and how to lubricate the linear rails exactly apart from a generic “apply grease on the axis rail” which is usually not the best way to grease a linear axis with runner blocks - all ball runner blocks I know usually have holes on the side to insert grease according to the manufacturer specification. If I take a look at e.g. Bosch Rexroth linear rails, the type and amount of grease and which holes to use greatly varies depending on the type of linear rail and the use case.
Could you tell us the greasing specifications (edit: and the suggested grease or at least its NLGI class) of the linear rail manufacturer you use?
Edit - Recommended greases for Bosch linear rails are:
Dynalub 510 (NLGI class 2, alternatives mentioned by Bosch are Castrol Tribol GR 100-2 PD or Elkalub GLS 135/N2) for the majority of ball rail, roller rail and cam roller rail systems
Dynalub 520 (NLGI class 00), Alternatives mentioned by Bosch are Castrol Tribol GR 100-00 PD or Elkalub GLS 135/N00 for Dynalub 520) for miniature ball rail systems.
In opposite to the expensive Dynalub, the alternatives are mentioned as suitable for temperatures up to 140°C (Tribol) or 120°C (Elkalub), which should be by far enough for the printer. I would suspect one of these should be suitable for any linear rail.
Yes, unfortunately the fat was clearly too little here.
Now we have to fix it again later and cumbersomely.
But that shouldn’t happen in this price range!
I had relied on the statement from MpoxDE, there it was said that plenty of fat was applied.
Maybe with him.
Yes, this is why my experience is it is advisable to always doublecheck how things are greased on a new machine.
I also dug a little further: while most linear rail manufacturers suggest NLGI class 2 for greasing, I did find several remarks at other places where people who built 3D printers themselves did complain that the grease is too stiff for use in a 3D printer where you get a lot of small movements and have rather low loads.
So, in case anyone is interested, here is a complete list of the Elkalub and Castrol Tribol greases of the viscosity classes that might be of interest:
NLGI class 00 (used by Bosch for their miniature ball rail guides):
NLGI class 2 (used by Bosch for their standard ball rail, roller rail and cam roller rail guides):
Castrol Tribol GR 100-2 PD
Elkalub GLS 135/N2
Rules of thumb I found:
the lower internal pretension of the linear guide is (either by intent or by lack of manufacturing quality), the lower the grease viscosity should be to avoid sliding of the balls whch would destroy the linear guide
the lower the grease viscosity, the higher the required service frequency
higher grease viscosity means longer times for grease distribution within the runner block.
higher grease viscosity also means more stable lubrication under load
after greasing, 3d-druck-community suggests to run in the printer by letting it move in e.g. large rectangles without printing anything for an extended time (mentioned are 3+ hours).
It would be interesting to see if the layer shift errors shown in other threads here can be explained by such a lack of grease or a lack of grease distribution as well…?
Do you have any idea what linear guide slides are?
The X axis has a 14mm rail, today I took it off and of course I lost a ball as well.
When blowing out the side pieces, one fell out.
1.5 mm has a ball in diameter.
slide width 31.3mm
Ouch, there are numerous different variants of those. If you want to replace the slide block alone, you will need to contact Snapmaker support - virtually every manufacturer of those has a different rail geometry.
Thanks for your feedback! The current lubricating instruction in the manual is an outdated version, and we’ll update it this week. I’ll pass your feedback directly to my colleague (who is responsible for the J1 manual). This kind of manual feedback is very much appreciated and welcomed! Thanks again!
Of course, I don’t want any new rails and Sleds for the time being, so I ordered new 1.5 mm balls. If anything, I’d rather contact support. I’ve been in contact with support and I’m waiting to see what Snapmaker says now. I hope it will continue soon. but first of all thank you for your support. I will report how it goes.
Hi, the x-axis is actually bolded in the video, but they both need to run the same, which it doesn’t. Today I will record the x-axis again without bold so that the comparison can be seen better. But it is noticeable that one camp is clearly blocked. If you have cleaned the bearings and pushed the balls through the channel with the tweezers, you can clearly feel it. I’ve done the whole thing four times now, so clean and grease, with high-quality oil for linear bearings and grease, no improvements.
One of the two sliders seems to move more easily over the length of the rail, so the root cause will have to be inside the slider (as opposite to a bent rail).
Things that came to my mind:
residuals of grease or dust in the ball cage
deformed or tilted slider
How did you remove the grease? Just by wiping it or with alcohol or acetone? The latter would be the most effective, but could be dangerous to the sliders’ plastic parts, though!
If the grease is silicone based, you are at a loss with organic detergents obviously…
Everything cleaned up nicely with isopropanol, the plastic can handle that.
There are no obvious defects.
Even with new balls, the slider doesn’t get any better.
I checked everything.
I even checked the channels in which the balls run with the magnifying glass, nothing to see.
Ja, den Support habe ich natürlich kontaktiert, läuft.
Ich denke die Jungs und Mädels haben eine kurze Woche, daher muss ich mich jetzt etwas gedulden.
Hoffe nur das ich den J1 wieder korrekt zusammenbringe.
Das Problem ist die Zeit, je mehr Zeit vergeht bis ich Ersatz bekomme, desto weniger Erinnerungen wohin welche schraube.
Ich denke, wir könnten (sollten) einen Deutschen Fred aufmachen, ist einfacher. Oder?