Hi,
i recently bought a craftbot plus less than a month ago. I bought it to upgrade from my flashforge creator pro. While at the store I listened to it print and it has this high pitcher rattling sound. Of course, when I took it home, these problems persisted. I am. It so sure they affect printing, but it can't be good. Something must be loose; but why? It's a new machine?

I have read the former posts about his issue, but I simply do not want to operate and tak apart a brand new printer which was supposed to be an upgrade. Currently, when I need reliable prints I still use my creator.

Attached is a video of the sound.
https://youtu.be/_RNs5_Xsy_4

Thanks for your responses
Erik

March 30, 2017

Erik Erik
Beginner
2 posts

9 replies


Hi, I listened several times, but the noises you referring to are had to determine.

If very high pitched noises you hear, mostly at the first layer (printed slower) than it's just the stepper motor singing because of the way the stepper drivers work / microstepping / stepper frequency works. (Sandor can provide the actual adequate terminology).

If rattling at higher levels and specifics speeds it's probably the balls of the lineair bearings resonating. There are two lineair bearings in each holder / pillow block. And the line of balls of each should be lined up from the two linair bearings to prevent rattling. Lining them up and good oiling should prevent that noise. I replace that metal bearings often by plastic ones, but sometimes that's not enough:

Other possibilities: the CraftBot is basically a very good musical instrument, with thin metal plates to amplify all sounds. So with a given print speed and hard tightened belts there's always a spot that makes your CraftBot sound industrial. Best to see if all bolts are tightened well and not tension the timing belts to their limits.

March 31, 2017

Bart ter Haar Bart ter Haar
Service partner
1463 posts

Hello Bart,

I appreciate your response. The sound is constant at low speeds as well as high speeds. The sound the machine is making is probably more audible in this video: https://www.youtube.com/watch?v=z19zedHWWrw and this one: https://craftunique.com/forums/view-thread/2418

The rattling essentially sounds like vibrating metals at a relatively high pitch. Anyway, I have seen in other posts like this one: https://craftunique.com/forums/view-thread/1491 suggestions on how to fix the bearings and/or replace the linear rods and bearings.

As the machine is new, I do not really want to make these replacements. Is this my only option? Maybe I should return it. I was looking for an upgrade with less issues than my Creator Pro.

Thanks again for your response.

April 1, 2017

Erik Erik
Beginner
2 posts

Look at this post. That shows how I fixed the most annoying noise of my original CB.

April 1, 2017

psanyi psanyi
Exalted
817 posts

Hello Erik: now I recognize the sound. It's indeed hairpulling. BTW: I have tested about 80 CraftBots by now (still learning...)

A while ago I thought that was always solved by replacing the bearings by plastic ones. And it does in 90% of the cases.
But that sound can also be solved by adjusting the line of balls of the original metal bearings and with enough oiling each 50 print hours (that's very often).
In some cases that sound can be eliminated by solutions as Psanyi points too, but not always.
I have changed CraftBots with plastic bearings and some dampener as psanyi did at the X arm, bit they still made that rattling sound.

Also (with older models) it helped to get some dampeners between the cable chain and the X arm.
Sometimes it helped to fasten all screws, certainly from the transparant sheets on the sides of the CB.
Sometimes it helped to loosen the lineair belts a little. As the base of the sound is the steps (interfering) of the two stepper motors driving the XY movement.

Sometimes nothing helped. That CraftBots are sent back to CU, or now in my own printer park.


April 2, 2017

Bart ter Haar Bart ter Haar
Service partner
1463 posts

Ive placed a strip of electrical tape between the metal piece that psanyi pointed out in his post and that noise is gone.
Carefully re-tightening the screws helped (there 3mm screws in aluminum so you cant go berserker on these), but the tape was the fix.
edit: Actually the thread is on the metal plate but still wouldn't go too far with tightening 3mm screws.

I didnt take the machine apart other than the four screws that hold the "gantry piece" (the metal that goes between the bearing blocks), I used small spring clamps to hold it up while I placed the tape between the "gantry" and bearing blocks.

Couldnt the double set of bearings be replaced by the longer version (xx ?) or is spacing wrong ?

April 21, 2017

BV BV
Honored
283 posts

BV wrote:Couldnt the double set of bearings be replaced by the longer version (xx ?) or is spacing wrong ?
What do you mean by wrong? :-) The length of the Y block is 67 mm, so if you use the 45 mm long LM8LUU bearing, then you can fasten it on one side only and it will not be at the middle. Or you use two 3d printed rings to keep it in the center :-) Almost the same problem with the X block, but that is only 48 mm.

April 21, 2017

psanyi psanyi
Exalted
817 posts

@psanyi
Ah, I only modeled the X bearings since I still use my printer, 19mm is a no for the long bearing on Y.

Thought of another possibility, on Y swap the front facing bearing for a long, although I haven't tried mixing bearings short+long it would give more contact area and theres room forward for the bearing housing to hang out some.

But if your saying CU uses two short bearings on the X blocks ? I think it would be advantageous to have one long bearing in those blocks and split the 3mm on the outside.


April 21, 2017

BV BV
Honored
283 posts

I think the original X blocks fix the bearings in the middle, so you cannot fix the long bearing with the original grub screws. Those screws are meant to go into the grooves on the bearing.

April 22, 2017

psanyi psanyi
Exalted
817 posts

I looked over the bearings, both bearings have a 1.1mm groove.
I guess if the grub screw was ground to a point it would lock in the groove.

Still like the long and short on 67mm and the long on the 48mm doesn't look bad either, but that's just me I guess.
Rattling Noise issue

April 23, 2017

BV BV
Honored
283 posts
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