Walmart? Would not have guessed they sold 80/20. Here's a more typical site that thousands of engineers will use today to purchase extrusion for all kinds of industrial projects:

https://www.mcmaster.com/#structural-framing/=1dhfwat

Or, if you're a makerspace in the market for larger quantities and want to standardize, find a local vendor of extrusion (80/20, Misumi, Futura, MB Kit, etc) that will have the oddball fittings you may need on hand locally.

It's true that 80/20 will not sell you their dies, but they are happy to give away free CAD libraries of all their parts. There are subtle differences between different manufacturers, but everyone makes parts that are compatible with it and you probably shouldn't depend on the tiny features that won't match. It looks like OpenGrid saw a proliferation of too many 'standards' that were not open-source, and thought "We'll make a new standard that will be better than the others because it's open", and ended up adding a worse (less strong, less adjustable) standard product with limited adoption.

On the electrical boxes, they seem to be proud of their homemade enclosures. What they probably don't realize is that you can buy an IP67, hinged, IEC-rated enclosure with continuously welded seams from Saginaw or Hoffman with built-in grounding lugs, backplane, and latches for $80.

> Walmart? Would not have guessed they sold 80/20.

they don't, their website is a marketplace just like amazon's, these days.

Walmart is a bit more picky about what sellers they accept, from what I've heard.

"Sold & shipped by Zoro"

https://www.walmart.com/reviews/seller/1122?offerId=B80929A4...

The article mentions 80/20:

> There exist modular construction systems that operate according to the same principles, like the T-profiles made by 80/20 inc. However, in the modular construction systems that we have introduced above, everyone is allowed to design and produce parts, as long as these parts are compatible with the basic set of rules.

Which also includes a link to http://www.8020.net/ .

For projects in which 80/20 would be overkill, there are luckily smaller options available, such as 15mm (openbeam, makerbeamxl), 10mm (makerbeam), and 5mm (nanobeam). I imagine the 15mm ones are the most popular because you can use standard M3 fasteners with it easily.

the whole metal fitting (no clue how to call it correctly in english, this was my best guess) is standardized just like the article suggests.

millions of manufacturers over the world, all doing their own designs, but you can screw most cabinet door hinges with the same holes in the wood just fine.

or vesa mounts. etc. lots of industries already saw how good it is.

now, others profit from the lie that this is impossible. like sony using its monopoly on some markets to try to push silly things like minidisc, memorystick, etc. or Dyson making vacuum attachments that aren't interchangeable with even their own equivalent models. Which make them filty rich since a fool is born every minute, unfortunately.

> The one that heats a water vessel has liquids above a non-sealed box with electrical wiring.

Which seems to be a standard feature on all 4 apartments/houses heating appliances I am familiar with, sourced from three different brands.

Friends don't let friends use 80/20.

I've used exclusively https://us.misumi-ec.com/ for all my extrusion needs. They're one of the best companies I've ever worked with. Every order is a "custom order" - you tell them what you want including cutting, tapping, drilling.. You name it. Tolerances for a 20mmx20mm is 1mm cut. 15x15 tolerance is down to .5mm !

Their prices are also very reasonable, and shipping is good. I've also had a weird question about tolerance of a right-angle bracket, and their system imported the data wrong. Told that to the tier 1 support, and they went and found an engineer. Yeah, 5 minutes from calling to talking to the engineer responsible for that line. (Damn!)

The only caveat is they can't easily calculate shipping the first time a package shows up in the area. But after 1 delivery to a zip code, they can accurately estimate it.

My printer in action: https://www.youtube.com/watch?v=7EG-x7TBVng

The scale of the machine: https://imgur.com/a/GJWSf4t

Discovering T-slot was a revelation for me, lego for "grown-ups" basically. There's a good reason why the majority of decent 3D printers are built from it.

I would guess that the majority of 3D printers by shipped units are made of bent sheet metal.

'Decent'.

- ed

I should qualify this, lest it come across as mere snark - from my meanderings on the internet and a couple of visits to 3D printing shows, the machines that seemed capable/large/demi-industrial were made from extrusions and t-slots.

Certainly, where it comes to rigid forms necessary for (none- heavy industrial) CNC and such, they are heavily used.

eg. Germany's BigRep http://c93fea60bb98e121740fc38ff31162a8.s3.amazonaws.com/wp-...

Ah. I was thinking something like the Prusa, which is $1000, and it’s derivatives which are $200-500. The BigRep is apparently around $40k. I think the cheaper printers ship in higher volumes.

As far as “decent”, I do a lot with my sub $1k machines. The expensive ones seem to work better, but the price is so high I don’t consider them. And I come from a background of CNC machining where I’m familiar with $100k machines. Now I’m really happy with my $500 printer.

Actually I was thinking machines like the Creality3D ones (like the Ender 3S, I just bought one recently) which while far from perfect perform miracles at their (<$200) price point, in large part due to having a stiff frame with few resonances due to being built from commodity T-slot components. Even the Prusa i3 mk3 now uses T-slots for the base, though in their case it seems to be more of a DFM improvement. You're right though that sheet metal is very prevalent in the mid-range 3D printers and is an excellent choice for machines built in volume.