can or can not

[Wick]

found something really interesting here from creator of RATOS: https://os.ratrig.com/blog/no-you-dont-want-to-use-can

hmm, what do you think?

[Buurman]

I like keeping things simple, and running usb is simpler than CAN, for sure.

Too bad you still need the board on your hotend/extruder side, but I do believe simpel USB makes it easier.

Does it change what kind of board you need? since most are USB AND CAN?

[smirk]

Can't fault his logic, up to a point. I am always a little leery of the "if it ain't broke don't fix it" ideaology as I've seen how expensive and challenging that becomes [putting right] when taken to extremes. I could apply his argument to klipper vs marlin (or 3d printers full-stop) and I'd probably never have made it here (to the forum and Voron's) if I had.

However, the notion you should only do things if they bring value (however you define that) is absolutely true. I've picked CAN as I wanted a reduction in wiring, I'm certainly under no illusion it's easier. CAN is a mature technology, just not in the realms of DIY/amateur 3D-printing where it still has a way to go. No doubt it will eventually get to the stage of "why wouldn't you?", but right now with the state of things it's a valid point.

[claudermilk]

He makes sense to me. If you are just wanting to get your printer up and running and work reliably CAN is not the way to go right now. If you like tinkering and just want to play with it to get it working just because, then why not? I kind of like the concept of just running USB, but I'm not sure how that would look on a printer and if it would actually help anything.

One major reason for CAN in automotive that he missed is weight. Switching from a wire harness throughout you car (or truck or larger equipment!) similar to our standard toolhead harness to a 4-wire CAN harness both massively simplifies the overall harness and makes it significantly lighter. When auto makers are chasing every gram to reduce weight in the overall car, that's actually a significant savings. Plus the network redundancy.

WIth the engineering resources available and standardized, non-changing environment of a car CAN makes total sense. On a DIY 3D printer, not as much. At least IMHO

[Wick]

Well I think he's right, usb cables nowadays are able to handle incredible amps, it's also simply one cable and by this easy usable for umbilical, speed is much more than can (if I remember right there were lots of probs with leds because of their data usage) and if the toolboard accepts usb as well i see nothing thats against usage of usb instead of can, except one: there's a need for a splitting board for separating Power and Data to get the 24V Power up ?

[Buurman]

And the usb plug can be a bit large and stiff.. but I guess that takes some searching to find a right one..

[mvdveer]

Interesting point of view and factually correct. BUT - it is only one person's opinion and interpretation of the data.

There are benefits to using a canbus in 3d printing, just as there are downsides. The same with USB. 

There are also opinions on canbus contrary to his. It is what drives innovation and improvement. It these issues aren't debated, progress stalls.

I have most of my printers wired the traditional way, connected to the controller board, and pi connected to printer board via USB. I also have two printers running a canbus on the toolhead. Have I noticed a difference in performance - No. Was can more difficult to set up then traditional wiring - Initially yes, but the second time around - NO.  I can also argue for those that are not confident in crimping CAN may be an alternative to traditional wiring.

Do you want to push the boundaries and live on the edge - then you CAN

If not - stick to traditional wiring.

It is a choice, and that is what is great about the 3d printing community - variety, but also innovation