Bed Mesh Just Keeps Getting Worse
After remounting and straightening everything I can think of, it seems like I'm only making things worse. I started out with a 0.4-ish range, and now I'm looking at over 0.9. What am I doing wrong?
Here's what I currently have, unheated and heated (60°C), respectively.
96 Replies
genetic-orange•2y ago
enclosed or open and have you used this guide?
genetic-orange•2y ago
3D Printers & a Whiteboard
YouTube
RatRig V-Core 3: How to Get a Square Frame
This video is for those who struggle getting bed meshed with their RatRig V-Core 3.
Please feel free to jump to the chapter you are interested in.
0:00 Intro
1:05 about the v-core 3 frame and bed leveling
8:26 what to take care of in the building phase
9:17 the right square
10:09 build tips
16:50 adjusting the frame according to your bed mesh
...
I thought I had, which is why I went through everything and made it straight.
He said the problems may lie in the gantry being too tight. He suggested using only 7 screws, so I removed every other one, starting from the middle.
This is what I got.
genetic-orange•2y ago
gantry def looks like it has some bowing but i dont think thats the issue.
genetic-orange•2y ago
genetic-orange•2y ago
step 16, does yours measure out 220mm at the rear on both sides?
It looks like it's... 220 on the front and... 221 on the back.
genetic-orange•2y ago
id start by getting the rear where it should be then adjust the fronts based off what the bed mesh tells you. you are doing a ztilt between adjustments right?
I just did. Now I'm running the heightmap again.
Okay, we've had... A change.
genetic-orange•2y ago
Based off the video the front left if your looking at the machine needs to come up.
So where the red is isn't the front?
genetic-orange•2y ago
Red should be front, i know it seems counter productive but he explains how moving one side up or down will effect the other corner
When adjusting mine I used a block i was able to screw into the 3030 to know where i started and adjusted from there inserting different thickness items in then pushing or pulling the 3030 tight to the spacer.
I lifted the front left by a hair. Did the z-tilt and got this.
genetic-orange•2y ago
min went from .945 to .860 so its going the right direction, id do it again and give it 2 hairs.
What do I do about the back?
How much should I care about the measurement staying at 220mm?
genetic-orange•2y ago
In a perfect world if there all 220mm it should be perfectly square, mine by no means are 220 all the way around i just gave the machine what it wanted by adjusting the front after getting the back even. I hover ~0.260mm deviation and thats good enough for me.
Alright. I'll see what happens.
The results.
Are we sure the red hump is the front?
The 0 point of the Y axis starts there, but that doesn't make sense for where the X's 0 is.
genetic-orange•2y ago
Im about 99% sure it is and your getting closer to flat off the changes
The z-tilt calibration suddenly started grinding.
X-axis is now grinding.
genetic-orange•2y ago
and yes your x gantry is hella bowed
what do you mean by grinding?
Stuttering, making a grinding noise, not moving enough. I think the tilting is causing this.
genetic-orange•2y ago
With the machine off see if the x and y axis move freely
Alright, something changed.
In the back right motor, the belts are moving up and down, slipping off the bearings and getting pinched on the edges.
genetic-orange•2y ago
Moving the idler pulley location slightly probably moved where the belt wants to ride, get it back to riding in the middle.
I'm opening the motor mount.
genetic-orange•2y ago
you should have enough room to loosen the grub screws and move it a lil without pulling it all apart.
Should.
I didn't pull the whole thing apart. I tried moving the gear, and it seems to have done nothing. The lower belt still wants to go up and down as it moves. I can't imagine what's doing that... Unless the belt is bad.
genetic-orange•2y ago
mine goes up and down slightly but it stays within the toothed pulley face, if yours has so much variation it can't stay on track might be time for a new belt.
Great... It's all but brand new.
genetic-orange•2y ago
Belt's still properly tensioned? and can you get a video showing how much movement it has?
It was. Gimme a minute.
This thing is jammed right up.
genetic-orange•2y ago
In that one spot it goes from the top down to the bottom in like 1 revolution of the motor, how do all the rest of the pullies look?
Alright. Don't really change.
genetic-orange•2y ago
hmm id start pulling the motor plate apart and see if you find anything funky, hopefully we can get some other input in here but i dont wanna start tagging people all willy nilly.
Took this from another person who was having belt walk issues
"the only logic for any belt to walk up/dn on a pulley is the either the angle of the pulley pivot axis is not perfectly perpendicular to the belt, or the next traverse point of the belt travel is not parallel and in the same plane as that pulley. EG: it you feed the belt off angle to the pulley it will walk in that direction."
So the belt probably isn't bad, it's all the funky angles I've introduced to this thing.
That would make sense as to why it's suddenly happening.
genetic-orange•2y ago
Yeah don't assume its bad just yet, based off your last mesh it looks like both front's need to go up. Bring both of them up some and move the machine by hand first to make sure it doesn't bind up before meshing
Why can't the Z gantries adjust for it? I thought that was the point of having a 3-point z-mount.
genetic-orange•2y ago
it can only do so much, and as long as your bed isn't bent i see no problem getting it flat enough. Also after you get it back to functioning and moving without binding, id loosen the xy joiners and retighten them since things have moved around and see if that helps flatten your x gantry.
I doubt it's bent. I used a straight edge and level, it's fine on all measures.
And the joiners? You mean the plates on the framework?
genetic-orange•2y ago
yeah those plates
but dont worry about those until you get the belts staying where they should
Alright. I'll put the old belt back.
genetic-orange•2y ago
You get it back together?
quickest-silver•2y ago
X gantry 100%, just took down my extrusionless mod on my 300 because of the shape of mesh(same as yours) and 0.7 variance
Hi, I had this same issue. I ended up putting a micro shim on the Aluminium block where the high point on your heightmap show (Yours looks roughly in the middle and then went from there. I guess I had a slightly bent runner, even though I made sure all the Alu blocks were the same height and tightened the same.
Well, here we go again.
What would you suggest I do now?
@kermit.sudoku , any suggestions?
genetic-orange•2y ago
What all have you changed?
I filed down the mounts on the X rail so they fit flush within the blocks, and realigned the Y rails. I've also tried adjusting the Y frames back and forth.
genetic-orange•2y ago
To me it still looks like your front left needs to come up but you do still have some x gantry bowing.
I know it seems counter productive but I followed the video and made those adjustments and got mine to under 0.2mm deviation
The heck did that?
genetic-orange•2y ago
What?
That random spike in the middle.
It was a fluke. Here's the latest.
genetic-orange•2y ago
Oooh okay yeah id keep repeating and bringing up the front left corner a little at a time.
I'm getting there.
genetic-orange•2y ago
What happened lol
I think I overcompensated.
genetic-orange•2y ago
Just a smidge
Getting there.
Ooh, something is happening.
@kermit.sudoku what do I do now? It's getting close.
genetic-orange•2y ago
leftside looks pretty even so id start working the right front up a little at a time
genetic-orange•2y ago
Not terrible now, if it was me id bring both fronts up an equal amount.
One thing i also did is after i got it fairly flat was loosen then tighten the back of the y rail to relieve any stress that it was under from shifting the front around
genetic-orange•2y ago
Got some pretty nasty x gantry bowing, id loosen and retighten your xy joiners where they attach to the xy joiner plates and see if that helps the curve out any
I tried removing the 4 anchor screws on the sides of the mounting blocks. That did nothing.
Then I loosened and flipped the blocks in between the rails so that they just slid in between smoothly. That did a lot.
I don't think this is trustworthy. Running it again.
I've made... a difference.
genetic-orange•2y ago
slide the scale z max back all the way to the right like it has been before
sub 400 deviation is definitely a step in the right direction and most would be happy with that, the mesh looks ugly tho
Like that?
I tried loosening the whole rail and got this.
genetic-orange•2y ago
yeah makes the mesh look less jagged and can see whats going on, looks like loosening it let the rail bow up. i would say tighten it back how it was working from one side to the other.
also how perfect are you going for? most people are happy with sub 0.4mm deviation on a 500
Tightened it back down, and seems to have done nothing. Well, nothing good.
I fixe it! I got rid of the hump!
I switched the top rail with the bottom and turned one around. That got rid of that stupid middle peak!
That is the best I have been able to get it thus far.
genetic-orange•2y ago
Hell yeah you'll never get it perfect but that is alot better than most strive for.
So in the range of .2 and generally flat is the goal.
genetic-orange•2y ago
okay also prolly wanna heatsoak it and see how much it changes as well