Aggressive Vibration on second hand v core 3.1
Hey guys, I just received a v core 3.1 from a friend as a gift fully assembled (i assume by someone else as he isnt the most technically minded) as he didnt want it anymore due to him being unable to figure out how to operate it. After conversing with some nice people in the general chat i was able to get it up and running.
Though after auto homing there is an aggressive vibration when trying to pass a specific point. I will record a video shortly. I have been rapidly thrusted into the world of advanced 3d printing, i am normaly used to modding ender 3´s. I am excited to join your guys exciting community!
164 Replies
1. try turning off the printer, disconnect motor plugs and gently/manually push the gantry and toolhead around the build area. if you cannot push it smoothly by hand there is no way a stepper motor will move it smoothly
2. if it does move smoothly when manually pushed then maybe the toothed pulleys on the stepper shafts are slipping.
check the toothed pulley on the steppers there should be one or two set screws
Thank you for your reply ant :) here, there is one spot with a lot of resistance.
so the gantry could be misaligned or more likely, the y linear rails are not parallel to each other
your ratrig is probably assembled by plates in the corners so loosening bolts can help you reposition the extrusions to change the skew. you want to make sure the top part of the printer is square, that is, x gantry is perpendicular to the y rails. y rails are parallel
and in the same plane
you can start by getting a square and check the inside corners for squareness in the top area
also review
https://docs.ratrig.com/v-core-3-1/v-core-mechanical
frame assembly
linear rails
x-axis alignment*
Thank you for all this info
sorry i am a bit confused here haha. is it the bolts on the inside of the frame that i need to loosen?
the bolts on the green printed parts at the corner, and the bolts on the triangular plate (outside I guess).
maybe finger tight. but you relally only want to do this if you've determined a part out of alignment already
finger tight so it's adjustable but not too much slop. then when the gantry is moving smoothly tighten more
Hello sorry I went to bed. I just measured both sides and they appear to be the same distance apart on both ends. What else could be a solution to this?
I’ve noticed when I pull on other belts when the tool head moves through the afflicted area there appears to be no issue.
I realize Ant's been helping you so you may want to proceed on that path or decide to take a detour. I can only tell you what I would do and I rarely take half measures 😉 ). Troubleshooting is a process that cant be done taking shortcuts and its important you understand the parts involved and how they interact. Take off the belts entirely. Inspect the belts, see if theres a spot that has dirt clogged up between its teeth. Check for rubbing on the edges.
inspect the pulleys and toothed idlers (all of them), rotate them manually slowly and use a torchlight. They all got bearings so they should all be smooth to rotate. make sure they are clean and show no wear and no dirt.
move the gantry slowly back and forth over Y. Basically, this should be so smooth, no nudges, no grainy geeling. Basically if you tilt the printer about 30 degrees, the gantry should roll by itself. If it gets stuck its wrong. If it moves jittery, its wrong. If you feel resistance moving it manually its wrong. You need to fix that before moving on. Important to notice here is whether it suddenly gets stuck, or whether the resistance builds up gradually. This could have to do with the rails and how its assembled.
Move the printhead over X. Same story as Y but easier as its 1 rail not 2. I dont expect an issue here.
Its difficult to tell you how to proceed at this stage, it depends on your findings. I suspect Y rails because its the most logical in my mind and its the most difficult part to assemble and tune properly, and hardest part to explain ;).
Thank you so much for your reply, it means a lot to have received so much information. I am really looking forward to getting this machine running as it seems like an amazing piece of equipment. I will now try and remove the belts and see if there is fluid motion. If that is the case, then I assume it must be something wrong with the rollers or the belts I assume? I will get back to once I have more information, but first now I need to try to figure out how to remove these belts 😂
Bookmark it 😉
I have removed the belts and like you say the gantry slides effortlessly very little resistance. What do you think would be the next course of action here?
did you inspect the belt teeth for dirt and wear?
They don’t appear to be that damaged, however, I noticed I am able to skew with a gantry quite easily by applying opposite directions. Should it be able to move in such away?
no thats very wrong.
Figure out where that movement is coming from. My guess its the 4 bolts that hold the plates to the carriage. Either that or the 2 bolts running through the green gantry blocks (and holds the idlers). Check both.
I’ve tightened all the bolts, but it does appear to still be wiggling. Is this not from the metal flexing from opposing forces or should it be extremely rigid?
did you check the 4 small bolts that hold the gantry to the rail carriage as well?
it should be stiff and rigid enough that when you move it by hand on one side, it directly follows your movement on the opposite side. when you hold both sides and move in opposite direction, it should feel somewhat flexy but go back to its original position
I’m not sure it’s meant to be making this noise either 🙈 ignore the donkey in the background
These ones yes
It sounds good, be it a bit dry
Or are you referring to the small positive screws on the side?
do you see those 2 holes on your picture?
peek in there, do you see hex bolts?
Yes I tightened the near one
On both of the sides
and the 2 big ones going through the entire assembly?
that hold the idlers and pulleys?
I will do them now
Can I just say thank you so much for your dedication
to be short: its impossible everything is tight and secure or it wouldnt flex like that. Something has to move for it to be able to do that. Go at slowly and watch closely.
I also see the rail isnt secured with all bolts. Check those as well and make sure the rail cant move sideways on the extrusion
Oh yes, whoever must have built this did not put all of the bolts the rail
oke that makes sense. The rigidity looks good to me, its a 500? it looks big but it might be wide angle on the camera. Either way, the fact that it has a little more resistance means you did something right tighening things up. What happens is that the carriages get pulled in an angle on the rail and it increases resistance. It looks like youre well within tolerances though. When you give it a push, does it stop immediately moving, or does it continue to move on its own for a bit?
Yes it is a 500 🙈 the guy who gave it to me as a gift told me it was broken and he couldn’t figure out how to use it
It does glide a little bit after pushing I will make a video now
I think thats too much resistance
Ok
we can try and fix it though. What you need to do is loosen the bolts on the rails, both sides.
Check if it moves freely, it should move without any resistance
Moving it fully back and forth slowly will settle the rail angle to match the carriage
I just did the bolt on the top and the two bolt pass through on the bottom
Sorry I dont get it
did you loosen them?
Yes
dont do that, they need to be secure.
loosening them also reduces rigidity
sorry 😞 I think I got a bit confused
no worries! Its not easy
fasten them again. The issue we need to solve is when you fasten everything, the carriage on the rail tilts a little bit. That angle causes it to bind to the raill. We need to losen the rail and allow it to settle in the same angle as the carriage
Oh! So I need to adjust the many bolts on the rail which holds the carriage?
It appears these are also missing bolts
yes all the tiny hex bolts that hold the rail to the extrusion (not the ones on the carriage itself)
not really an issue as long as they are spread out its fine
if its only 2 or 3, Id be worried 😉
loosen them all, and see how it moves. Do it slowly then see if it will move by itself with a gentle push
when you grab the rail at an end, you should be able to wiggle it sideways
These are all done up very tight
😭
i hope your allen key wont ruin the heads
be careful
cool. all four ends are loose like that?
I’m about to do the other side 🙈 trying to be careful along the way
It’s almost like someone used a screw gun on it
oke take your time
Sorry my Allen snapped 😅 had to go find another one
omg
They are really tight in there.
Maybe this is the cause of all the problems
thats crazy. No stripped bolts ?
Not that I can see, maybe mine was just weaker steel then his
haha yeh
if you have those bolts spare, you may want to replace them while youre at it. When they have been this tight, they weaken. You might risk stripping them next time you need to loosen or fasten them
I would replace them prematurely
Yeah I will order some new ones to replace it, I only received the machine 2 days ago so I’m still new to the world of this advanced 3d printer stuff haha. Normally only mess around with ender 3s 😂
Ok they are both loose
The gantry slides easily now
Careful with nuts and bolts. They are addictive and you never seem to have enough. I started with 1 case.
😯
Cool. So heres what to do next. Move the gantry all the way to one side and then move it back just enough to clear the first hole. Fasten both sides while keeping the gantry there. Then move the gantry to the next hole, and fasten both sides. COntinue until you reach the end. In between, feel the movement and stop if it starts to bind again
if it starts binding, it means we have another issue (this can get complicated very quickly Im afraid)
Hopefully it will continue to move freely 😄
How tight should I fasten the bolts?
I’m assuming not as tight as before 😂
I guess just enough to be secure
when you loosen it and you give the allen key a fast twitch to fasten it, you will hear the t-nut lock in place. Then just finger tight, and give it one press of the thumb
you shouldnt need to use the long end of the allen key as leverage. Keep it upright in the bolt and tighten it with the short end with just your finger and thumb. THen you squeeze as tight as you can you'll never really overtighten them
hope that makes sense haha
Tighter than when it was loose, obviously. But I think it just needs a little bit of lubrication.
I think its good enough, much better than it was
Thank you so much so far my friend ❤️
youre welcome
I think there is something wrong with the stepper motor cage
possibly, but for that we need to return to when we started (you didnt fully answer the question on the belt when we started the gantry 😉 )
Oh yeah
I think I need to open this up because it is not sitting correctly on the motor
ah your belts are still in there
Yeah
oke
well open them up
lets see how that looks
be careful there are tiny shims in there you dont want to loose
you might want to check the manual first to see how its assembled, so you know what to expect
Ok
I removed the motor but now I will try find out how to open the box
PS. If you removed the steppers you removed the pulley with it. You need to place them back before you can route the belts correctly.
The belt looks great on this side
do you see that dirt?>
bottom left corner where the axle is coming up?
Hmmm the other side not so much for the belt…
Yes
that dirt there most likely belt rubbing an edge of a pulley
exactly
There is also dirt on the opposing idlers
yeh that printer has got issues haha
I mean, I guess he wasn’t wrong when he gave it to me as a gift saying it doesn’t work 😂🙈
what do you think would’ve caused this? Do you think maybe it was too tight?
hmm no just overtight belts wont cause rubbing. the toothed pulley on the stepper is adjustable in height, thats one reason
another reason is more complex; when the printer frame is not square and the the belt is running at an angle from front to back, it will run up and down the pulleys as the print head moves around.
lets say you got your work cut out for you 😉
🤯
I guess for now, I can try just reassembling it? And adjusting the height of the stepper motor teeth?
yes!
And if that fails, I guess I need to do a full rebuild
Which is probably for the better anyway seeing as how it was put together
Im not going to walk you through the steps of full 
I don’t expect you to don’t worry
😂
I am already overly grateful for the assistance you have given me so far
put the steppers in place see if you can route the belts
ive received some I give some. I guess thats how it works? 😄
Too route the belts don’t I have to close the enclosure?
no dont close em, you wont be able to run the belt through
check the manual and make sure you understand how it should be done
take the other one apart as well
check the order of shims etc, make sure its done right
no way of knowing what the other guy has done with it and this is your chance of doing it right
hang on let me check real quick. Ive replaced mine with aftermarket so maybe youre right. Give me a minute
No problem :)
yeh oke. it puts the idlers in place, then the belt with a generous loop, closes it and puts the stepper with pulley in (through that loop)
again: mind the order of the shims
Yes one was installed incorrectly
With a shim in the middle of the three bearing stack
haha ok
makes you wonder what else is wrong ... 🙄
😬🫏
OK, just of me holding the stepper motor in place. This is what it looks like.
yeah, dont forget the lower belt, it needs to run around at the bottom there as well
👍
Ffs one of the shims fell on the floor. It’s time for hunt for red October 😰
. . .
re-route that wire as well. You dont want that belt rubbing against it. route it the other way and fix it somewhere with a tiewrap or something
Still trying to find the washer…
expand your search area 😉
these things can roll haha
Yeah…
I feel like such an idiot
Is there anywhere I can buy them from?
Uh Im sure you can ... you can ask in the v-core channel. I think they 1mm precision shims
dont run the rpinter without it though. It sucks but you should really wait until you have a replacement (or find the one you dropped 😉 )
Ik
That’s why I’m so annoyed at my self
shit happens ... ive learned the hard way too 😉 haha
gravity's a bitch 🤣
Well thank you for the help. You have been amazing. I will just have to wait for a new shim to arrive
my pleasure
Do you mind if I add you as a friend?
actually I do 😉 I dont keep a friends list and deny friend requests. DOnt take it personally though
No problem
I do have washers of a similar thickness. But I assume this is not the correct way to go
same inner and outer diameter?
they dont need to be similar, they need to be exact
use decent calipers to measure
Google Docs
Public V-Core 3.1 BOM
Public BOM
SKU,HW3008MK,Rat Rig V-Core 3.1 - 200mm Long Parts
Rev.,12/09/2022
QTY,SKU,Item name
6.32,HW3272RC,T-SLOT 3030 - Black Anodized - By the meter
0.322,HW3262RC,V-SLOT 2020 - Black Anodized - By the meter
4,HW2911GC,Linear Rail - MGN12 300mm + MGN12C carriage
2,HW2352GC,Linear Rail - MG...
row 74
Ah it’s unfortunate. It will cost me €25 in shipping
seriously? from where?
thats rediculous ...
where are you at?
I live in the middle of rural Spain
Put my post code in and that’s the calc from the ratrig website
ah yeh ok
portugal is a few hours drive 😉
Ah I’m guessing that’s where you are haha
but seriously, check spanish websites or perhaps a car or bike shop nearby?
Im in extramadura
hardware store
Yeah maybe. But they tend not to have a lot of stuff here
Will try though
when you order somethign extra, is it still 25 shipping?
Most likely
I will have to go to the computer to check
weird its so much
The problem is, I was trying to fix it in the same area as my donkey food storage. So it is literally a needle in a haystack.
if you have a magnetic strip from something sweep it over the floor
Will have a look later 👍
@nebulator it appears that shipping cost doesn’t change, should I also buy new belts?
maybe there are some other perishable items i should stock up on also
Morning! Well that thought has led me to 10 cases of nuts, bolts, shims, heat inserts ...
Well having a spare belt will serve you well one day. Those flurry fibers on the edge didn't look like it would matter much. I'd cut that off (the flurry fibers) and reuse that belt. When its worn or snaps, replace it. Or use the new belt and keep the old one spare. its up to you.
Having an assortment of m3 hex bolts will be handy. some nuts and shims to go with it. Personally I shimmed everything that would fit a shim. Loctite 222 is handy too when you have some bolts or nuts coming loose.
Guess it depends on how much of a tinkerer you are 😉
Thank you 🙂 Will do
I take it you didnt find that shim?
unfortunately no :l will look again later today
crap ...
did you actually see it fall on the floor? Perhaps it got stuck between elecrtronics parts, behind a pcb or in the groove of the extrusion?
i didnt see it but i heard it bounce a few times
is this the name of the belt? Timing Belt - 2GT 9mm (By the meter)
i have ordered it all 👍 hopefully it arrives soon
yeh thats correct. If I had seen it sooner (sorry) I would have advised to get an original Gates belt
"ignore the donkey in the background". Hahahaha, that was the most funniest thing on this discord ever.
Thinking about it now I can see how it would be a bit strange for a normal person 😂😂🙈🫏
@nebulator I found the shim!
I guess there isn’t a way to cancel the order now though huh
if they havent sent it yet, why not?
i cant seem to find the option on there website to cancel the order, maybe i have to email them?
I just submitied a request, hopefully they get back to me 👍 now to rebuild the printer! I have noticed some of the plastic has been damaged on the toolhead so i will print some replacements now while i rebuild the 3.1
@nebulator Almost finished reassembly. About to have dinner. I think the remaining wobble in the xy gantry is due to xy joiners being slightly warped. I will maybe try to reprint them if it becomes an issue
@ant @nebulator thank you guys so much for your constant support. Of the following your guys advice is is working again!
Ignore the broken plastic
Nice job!
It will be fixed later :)
I am sort of glad that this happens as it is taught me a lot on how this machine works. It wouldn’t have been possible without you guys assisting me and I thank you all very much. ❤️ I can’t wait to be more involved in this community as I learn more.
🥳
Glad you got back together. Enjoy!