Yup, it sucks. Should have used screws. Lesson learned. Drill all the holes with a drillmill or spade, screws, lighter finishing pass. That 0.85 left a rougher finish than the thin chattery one.
The outside ones are pretty easy with snippers, it is the small inside ones. Those will all be pockets next time for sure.
I can not get a super great edge finish with the plasma on aluminum yet…if it is even possible.
That’s crazy how it can do so good one time and then total opposite another. Makes it real damn hard to iron down some good consistent settings lol.
Time for a LR3/4 Water Jet!!!
Building a new frame.
The process is very similar for a corner bracket frame. Panels are easier to build but harder to make.
Building on a very flat and solid surface make this part easier.
I stop here to add the hardware in while it is easy to reach in. If you are building a corner bracket frame feel free to build the whole cube.
Liking the documented build approach 
1/4" HDPE panels?
I don’t understand “Cut all extrusions 2-3mm short” ? Having been blue taping together extrusion meant to be the same size, then cut on chopsaw (after first double checking blade is perpendicular to back stop).
Curious what’s the minimum tab width and height sizes folks are configuring when milling, so the Alu parts to stay in place during the cuts, but are not a PITA to remove and cleanup?
Typo? Was expecting… “Do NOT use twist in T-Nuts”
Whether it’s panels or corner brackets you are using to hold the frame together, those are what’s providing the strength and keeping it all square.
cutting the extrusion short, like this:
Allows you to square it up with the panel or brackets without extra length getting in the way.
The reality is you want all the pieces to be in the range of exact length down to a few mm short.
cutting a few mm short just ensures you aren’t accidentally slightly too long, and stopping yourself from being able to make it square because the extra length “kicks it out”, so to speak.
If that helps…
@Jonathjon and I used padded screws instead of tabs. A little more upfront planning, but less clean up work after wards
I have bunch of 9.5mm HDPE from an impulse 50% off buy.
If I make more I will do it this way for sure!
Yeah, guess that’s ok providing panels are very rigid. Adding interior panels would help if using thinner/flexible panel material if looking to over cut extrusion. e.g. I wouldn’t overcut extrusion like this if doing just exterior 1/8" polycarbonate panels.
Ideally, should cut extrusion to intended dimension in batches grouped by intended length, using calibrated perpendicular/plumb Chopsaw Miter Saw. That would avoid need to overcut.
Guess I’m not used to seeing gaps in framed assemblies. At first glance, if I was walking by a machine, looking at it for the first time, my assumption (rightly or wrongly) would be that the gaps are a fluff up.
Could always fill the cracks with Bondo
Even 1/8" Polycarbonate panels are way stronger than any of your extrusion joints. Like sheetrock on your walls. The 1/8" PC is is weak only in the plane you don’t care about.
My saw is as perfectly plumb and calibrated as I can get, but it’s very difficult from hobby grade tools to get perfect cuts. You even have things like saw blade deflection etc. Many of us are using regular miter saws, etc. to build these, and perfect is hardly attainable.
Even just 1mm short will stop you accidentally fighting against the extrusion to make it square
It’s a choice, but it’s more a tip to make the assembly as easy as possible. You can certainly cut perfect on the line, and shave it down later if you see that you are struggling to get it square
I agree with Mike here. I used 1/8” polycarbonate on my V5 and it’s super rigid in the right ways. Even with the big holes cut in top and front panels. My extrusions are only held together with the panels. I have no other corner clamps or anything. And it’s a super rigid super square printer. I was hoping to run the Calilanter skew print before I had to leave but I ran out of time. We will see just how good it is in a month when I get back home lol
I did the same thing here as well. Even went as far as cutting them all 10-20 mm long and taping all the matching pieces together. Then trimming off just a blades width on one end. Then pull my measurement and make my cut on the other end. That way all pieces that needed to match were the exact same. Well as close to exact as possible. Taking my time with the cuts to have as little blade deflection as possible
The frames are only stress in the plane of the panel, any other forces go to a different panel. Perfect joints would only help a bending moment in one direction, and do nothing in the other. When building a cube, the surfaces do all the work.
For my MP3DP v4 build, I spent a lot more time calibrating, cutting and re-cutting acceptably square panels on the LR3, than the time taken to cut batches of taped extrusion to the same length. Using a nice, but not especially fancy Dewalt DWS780R 12" Chopsaw Miter saw, ~12yrs old, but not used daily, it’s had a relatively pampered life, but more than paid for itself. Bought out of frustration with dimension/feature limits of my 10" ryobi.
This is interesting, from ease of assembly perspective.
Vibrations?
I cut my panels and they are square to under a quarter mm across 640mm diagonals. This is how my LR sits. I squared it for that video I made a while back and all my cuts are still dead on. I use it 3x a week at least. Once you set it square it stays.
This is also why I say a printer build is an advanced build. Everything has to be very accurate to build a very accurate printer without a ton of skew compensation.
Anything you might gain from a perfect non-welded or otherwise reinforced seam in this application gets carried over to the next face. Side to back is supported by the top and bottom. A perfect cut is only a good idea if you are using it to connect something on the end.
Have you seen the process Prusa goes through to verify the extrusions they use for the bed-slinger, just to mount the end plate, They could bypass all that by mounting it to the top of them
Don’t forget the corners are re-enforced with 5mm metal plates on both sides.
For crack loving folks here, maybe intentionally make the extrusion short enough to allow wiring to easily pass through and ease routing wiring?
As long as you dull the edges. I tuck my wires into the extrusion channel. I think you can see it in the pictures.
This was my process for the panels as well. When I redid my big lr3 Ryan had just put out that video shortly before about squaring it. And I did the same thing at my full table size. And I’ve built many drawers and a few cabinets since then that have all come out dead square. I also double checked square before cutting the V5 panels and it was still dead on! After that it was just drawing up what I wanted on the cad (Ryan hadn’t done his yet) and exporting the dxf. Every panel came out dead square! I spent a little extra time on the back panel trying to think of every wire that needed to come through and that really made things a lot nicer when it came time. And I still missed 1 wire and should have moved 2 others to a little different spot. But I think my wiring looks cleaner than any other build I’ve ever done. I plan to take it a step further with the V4 to v5 conversion back panel. But that’s mostly because I have the next month at work to lay everything out that much nicer and the experience gained from building the first V5
