Y-axis movement makes the whole machine vibrate

the whole bed plate hums/vibrates while moving along the Y-axis. I’ve lossened and retightened the modules a couple of time to no avail. Anyone else have this issue?
This is an A-250.

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Please remove everything from the Y-axis modules, listen to ascertain if the noise persists, and report back here. Poor quality control in the pitch of the lead screws, widely reported here, might be causing the noise; removing mechanical linkage between the lead screws will provide information.

So there’s this thread where staff said it’s a problem and they ended up replacing modules Is this buzz sound normal for 3d printing?

And there’s this thread where they explain it’s normal Excessive Noise

So I don’t know anymore. I guess contact support?

Hello

I am the “Is this buzz sound normal for 3d printing?” post.

As it turns out, Snapmaker ended up saying that it was normal, despite saying in the post it wasnt.

However, I have found that the reason for the vibration is loose linear modules.

The looser it is, the more pronounced the vibration becomes. At least in my case.

I have a 2nd loose module now. The whole bed rocks up and down and it actualy makes grinding sounds occasionally now.

My box of replacement modules that I purchased (2 spares plus 1 replacement) arrived today and I will be eager to change them out to formally report my 2nd bad module for warranty replacement.

From the time they told me they would give me one to the time I received it was about 2 weeks, but the time it took to get to the point where they said they would give me one was probably more like 4.

Make life easy, video document evidence and post on the forum, refer to link to post in your email to support.

I think Snapmaker will probably say there is an acceptable level of looseness of the module, what the threshold is I can’t say, but mine is particularly bad and has gotten significantly worse.

I would hope that the module design has been addressed in some fashion, there was some speculation about it not meeting the specifications, but I don’t know if its more that or the design is flawed.

I also know they are working on “new silent linear modules” so I would expect that to be a point to argue about with Snapmaker if they are denying replacement.

I cannot say for sure if the vibration is enough for a problem, but if you were to for example swap the module around causing the noise with the print head and showed evidence that it was printing like garbage, I don’t think they would have any choice but to work with you on it.

It might sound shady but if you are particularly upset about it thats one potential way you could at least test the theory.

One other thing: I’d hesitate to disassemble the module itself without snapmaker’s blessing. There is talk that they have denied warranty for doing so, despite providing instructions for doing it. Unfortunately, you are going to be at 1-2 weeks before a repsonse, so the more information you send them at once the better, otherwise you are playing email tag.

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I got clarification on that from Rainie via a support ticket.

I’m interpreting that as they’ve had trouble with people breaking something, and they won’t warranty something you break if you try to disassemble it. So if you’re mechanically inclined and carefully disassemble, minding the internal cables and interference fit microswitches, it’s pretty straightforward. Check out the internal pictures from @sdj544 Excessive play in x-axis linear module bracket - #8 by sdj544

Thanks for your input gentlemen. Support wants me to run some measurement tests of the Y-axis movement; so I’ll do that first. I’ll also check for play in the linear rollers as well. and make sure the blue pads are in place. I probably won’t open module if there is excessive play until I hear back from support.
My serial # is 8, so I think there were several mods done on the production line since it was built.
I’ve bookmarked your post Moosejuice and will be referencing it during my inspection. I have a piece of glass coming tomorrow and a piece of steel plate later in the week so I can sort out the bed level issue. The little stickers I’ve placed have mad a significant difference though.

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I have what may be a dumb question. people talk about the y-axis the x-axis and the z-axis modules. But the modules are not positioned specific, are they? There was no indication on any of the modules that stated what axis they belong to.

That’s correct. They can all be used as any type and are all identical.
It’s their movement direction in the mounted position that determines if we refer to them with X, Y or Z axis.

Just to add to that comment.

Disclaimer: I’m not a staff member, I’m still waiting for my SM A350 to arrive, this information is based on me being active in this forum since July.

There is some evidence that not all linear modules are as identical as would be ideal. The impact of this is that if you were to pair two modules that were not evenly matched, you risk getting issues with what’s been described as a “bump”, which is really one module running faster/further than the other on the same axis and then forcefully being dragged, causing the bump.

There are plenty of descriptions of this behaviour on this forum.

Whilst not ideal, it doesn’t have to be a showstopper.

If you test the modules before bolting them down, you can likely find pairs that travel at the same speed/distance.

There’s posts in this forum describing how to do this.

Note that we’re talking about millimetres, not centimetres of difference.

If your SM is manufactured more recent than about September, this should be fixed, but it’s unclear exactly which orders had any issues - it doesn’t appear to be universal.

That was much more than I planned on saying on the subject, but thought it might help you and others.

Onno

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It’s actually one of the first ones off the line so there may be some issues.

I performed the Y-axis inspection and there does not seem to be an issue with the modules. I’m starting to think that the noise might be originating from the head. I think I still have a vibration analyzer that I used to use at work. Here’s a clip of it. Let me know what you think.

In this one I’m holding the head in my hand. The machine still has the noise/vibration.

So I removed the X-axis. Noise and vibration still present. Next I will remove all the rails and put them on a rubber pad. It seems to be the dust rails vibrating inside the rail; setting up a harmonic vibration throughout the machine. I’ll know more in a little while.

Yes, there is a degree of resonation that is been confirmed from snapmaker

In my personal experience, i had a LOT of it, because the bracket that comes out of a linear module was loose.

This was leading to my parts not being round (it was on the print head itself) and i ended up swapping rails with one that the bed rides on, which helped alot but it became noisier.

That was a short term solution to replacement, which i have since done

Not that this is necessarily your issue exactly, it certainly was mine - and snapmaker is designing “quiet linear modules” so with that said i think there is just going to be some level of noise from the rails without that “upgrade”

Edit i guess i already made these comments on this thread, sorry.

I can handle the noise. The real issue is the harmonic vibration that is transmitted through the machine and adversely affecting the print. I’m beginning to think it is the thin dust cover that is vibrating like a reed. Like the mouth piece of a saxophone. I think I’ve identified the worst one. I will finish disassembling the machine and test all the modules. I am certainly not going to pay for an “upgrade” for a non functional machine. While a dust cover is a good idea; this one should have been a non-starter.

Yeah the dust covers do tend to move a little bit, I’m not sure but maybe its possible to get it under the “stretching” bracket better to pull it tighter or something.

Perhaps a little component can be designed to assist with that

Regarding issues you are seeing in your prints, are you seeing wiggles in your lines?

I think they call it artifacts or ghosting

I was clued in on some tips on some “enhanced procedures” for further calibrating the machine, and i’ll tell you that there is one that had a night and day difference in how my prints were coming out in that regard…

If you havent done it yet, you may find that the vibration isn’t causing as many problems as you think

Check out this linear advance adjustment procedure

Hopefully you make some progress in getting the machine running to your satisfaction. I know so many people on the forums here have a hard time and we are all just trying to work together to make it better ya know?

It’s a small design deficiency, but the piece of metal that holds down the metal strip dust cover is the same one that tensions it. When tightening that little piece down, it tends to rotate. The A350 comes with a little spring clamp that applies tension but down almost nothing to resist rotation. As a result, it’s pretty easy to get a dust cover strip that is either not very tight or not very straight or both. Either of those deviations from ideal will lead to a strip that will be noisier under vibration.

yes i have seen about that, thats why i was wondering if perhaps we could come up with a mod to to pull it taughter or something

just a thought!

The most conservative way of doing it is to make a new tensioning device. It needs four elements, as I see it. The tensioner that ships with the device has only the first two.

  • A way of applying tension between the inner edge of the hold-down washer (it’s a rectangular washer) and the end of the linear module.
  • Access holes for the hold-down screws. This required because the obvious way of applying tension occludes the screws.
  • A pair of flats that meet the sides of the washer and prevent rotation. In simpler terms, a built in wrench.
  • A contact surface for the top of the washer so that it can be tensioned without the screw in place at all. This is for ease of use, because if the tensioner doesn’t hold it in place, you’re now juggling three small parts to make it work.

This could pretty easily made with a metal “shoe” that has a recess the same shape as the washer. The depth of the recess is just shy of the thickness of the washer so that the washer stands proud of the bottom surface of the shoe and so that the shoe does not have sliding contact with anything. Add to that (1) a fixed depth clamp to the opposite side of the module that holds the shoe down, and (2) a screw clamp to the end to apply tension.

You can’t apply more tension to the strip as it is woven through 2 plastic slides under the carriage. The strip already creates a decent amount of back pressure on the carriage; which is were I think most of the vibration is coming from. I disconnected the strips from either end of the Y-axis module and allowed then to move with the carriage. The difference was significant. Next I am going to lube the Y-axis strips with some 3 weight oil to see how it compares. Both the top and bottom sides of the strip would have to be lubed. So you would have to remove the screw from one end of the module and wipe the strip with an oiled lint free cloth for it to work.