Clarifications about Frame Squaring Video?
I'm looking at squaring up a V-Core 3 400mm frame that is about .65mm out of square, and I'd like to double check a few things about 3d Printers & a Whiteboard's video about squaring (https://www.youtube.com/watch?v=h7ZTq2dDTkM)
It sounds like for just a tilted bed mesh, the A/B points (the X axis in the front) is generally always going to have the actual corners defining one plane (since this is where the two points of the bed triangle are?)
It sounds like corners D and C are hard to adjust, so generally you're just adjusting the Bar [AD] and Bar [BC], except we do it on the A/B ends of the bar due to D and C.
Questions:
1) Because A/B make up one edge of the triangle in the actual graph, it sounds like we're really only worried about adjusting D and C to match?
2) We adjust D and C corners in the mesh generally by moving the segments on the A/B corners?
3) Is there a way to make the printer do the bed mesh faster to test more?
4) How difficult should adjusting the corner be? I took a hammer (with a block of wood to soften it), undid the bolts indicated in the video (the 3 vertical, plus the top ones) and gave it some good strong whacks but it doesn't really seem to be moving, could it be that I over tightened the horizontal on the opposite end of the AD/BC segments and that's preventing it from twisting down a bit?
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
...
16 Replies
correct-apricotOP•2y ago
Reading the comments on the Youtube video makes me think I need to make the A corner go up to counteract for D being so low.
B corner comes down to lift D I'm in the same boat right now flatening mine
Be sure that, each time you make an adjustment, to run a ztilt before running a mesh... Otherwise you won't see the effect of small changes
any1 thought of using a jig to make a perfect square ?
you can buy 1" or so thick L squares, whci are designed to clamp on to square stuff up
example from amazon
LOL no amazon here...........i'll make my own jigs
aliexpress, any major on line tool store...was just using amazon for the pic of such a tool 🙂
yeah i know
my solution will be drawing the frame sizes on my sacrificial work bench, and make tack some wood cut straight on the lines
1st, 680 x 700 for the electronics frame
Personally I used a capentry L square clamped to the table and butted my extrusions up to it then a second square at the opposite corner. A couple of motorcycle tie-down ratchet straps to pull it all tight together then bolted the joiner plates on
your idea is just as valid
6 of one , 1/2 dozen of the other
i'll tack them in place with the nailer, check squareness mesuring diagonals, then a couple of screws to make it all solid.......
and that for all the sides
One note though. Even though may get a single 'plane' square, once you stand them up for the 'box', things change. Once on its 'feet' the box will rack (regardless of how small)
To compensate for my final table and seated location, I drilled out the bottom surface corner plates to clear the M8 sized center hole of the vertical extrusions. I threaded them and inserted large leveling feet threaded into the vertical extrusions. This allows for final squaring when you decide where it will live.
i was thinking of doing that as well, like squaring the washing machine 🙂
exactly
correct-apricotOP•2y ago
I think you need to build your rig upside down. It's really hard (even with clamping the extrusions to a square) to get it to stay square for all the corners.
By starting with the top 4 extrusions (which is the plane we're tweaking) hopefully those can end up quite square and flat with each other, and then it's less important that the rest of the frame is as square
Since if one of the Z corners isn't the same height the z-tilt will compensate (obviously they need to be pretty close to straight up/down so you don't get a skew as you print high on Z), but the Z tilt can't compensate for the top plane not being flat.
open build (open front) upside down doesn't really help ha BTDT but do understand the premise. That was how I got my original 3.0 squarded up
side note.... recently revisiting this 'frame tuning'.... I took a set of digitial calipers and attached them to a long steel ruler. I'd also made a 'foot' to simulate the other end of a caliper. so in essence I had a 600+mm long set of dial calipers. I used it, bottom tip into the side groove of the bottom horizontal extrusion, with the 'real' caliper edge touching the rail itself. Measuring all four corners I was able to measure...and with re-running the 11x11 mesh several times, come up with a relatively consistent measurement to adjust spec for my machine (everyones mileage WILL vary)
Minus the measurable bed sag (under it's own weight)
I'm currently at 0.02mm across the entire 500 sized bed. As to the bed self sag bowing.... Hopefully by the end of the week I will be posting a fix for that! (waiting on parts and CNC router table work to finish)
Tbh, pursuing perfectly square frame is a waste of time... It's not humanly possible to build perfectly square... Accept some reasonable degree of error in your build and be prepared to fine tune things once you are able to generate a bed mesh
Right angle jigs like those shown are more than enough to get you a reasonably square frame
I used them myself in fact