Connecting to a CNC machine, pros and cons of USB vs PP vs Ethernet etc.

[Neale]

Theory and Experience work together for advancement but experience ultimately Wins and as the final say on what works and what doesn't.!!!

I'm not sure that I agree with that (I think that testing has the ultimate say) but that statement is only based on my experience and there's no theory to back it up...

[HankMcSpank]

Would it be too presumptious that on a forum called mycncuk (which has a "mylittlepony" vibe to the name!), that most are hobbyists? In other words, not everyone wants to go to the far end of a fart over 'ethernet vs USB' (which would need a forum called IusemyCNCmachinetomillindustrialhardenedsteel.co.u k - which granted isn't as catchy)

I'm a dabbler (I use my CNC to make pcbs) & I was pleased to see the back of Mach3 ...putting on those retro stick-on Bradley Wiggen-esque sidebruns & a pair of massive Lionel Blairs just to do a CNC session was a bit much. It was therefore like a breath of fresh air to migrate to cnc-usb, which uses erhm USB ....& I've not had one bit of bother with it. For the sake of balance, that's not to say others haven't has problems, which prompted the owner of cnc-usb to illustrate what a difference the actual usb cable can make...

[Jon.]

My god i must be doing everything badly.. cheap ass 5m usb cable coiled up, wrapped around extension leads and all sorts and running off a laptop. I must be very lucky.

[JAZZCNC]

I'm not sure that I agree with that (I think that testing has the ultimate say) but that statement is only based on my experience and there's no theory to back it up...

Ok I'll amend it to what was meant and say Ultimately Experience testing wins.!!. . .

[Neale]

Ok I'll amend it to what was meant and say Ultimately Experience testing wins.!!. . .

I wasn't being very serious! My personal problem is that anytime someone talks about the value of experience, it reminds me of my father whose attitude was along the lines of, "That's the way I've always done it, so that's the way it has to be done!" Didn't leave him much room for improving anything... I cheerfully admit to stealing the results of other people's experience where they've been kind enough to publish it - which is why I have a CSMIO-IP/M waiting to be installed, complete with Ethernet connection and 24V differential signalling.

My god i must be doing everything badly.. cheap ass 5m usb cable coiled up, wrapped around extension leads and all sorts and running off a laptop. I must be very lucky.

FatFreddie said he had so many problems with USB and his 3D printer that he gave up using USB. I've been using USB with my 3D printer for more than 3 years now and I've never had a problem with it. There's nothing wrong in principle, it's just that the safety margins with respect to noise are much lower than with Ethernet. There are also issues if you rely on the 5V supplied via the USB port as this can be a bit flaky as well. My printer controller has a separate supply - maybe that's why mine is more successful? Don't know but it's a case where experience gives different answers depending on who you ask.

As for theory versus experience - I use Ethernet-over-mains to get a network connection to my garage as the layout of my house makes the wifi signal a bit flaky out there. That signal goes through two ring mains, 3 MCBs, and an RCD. I wouldn't expect anything to get through that lot (based on the principles of high-frequency signals getting through a bunch of inductors), but I tried it, it works, and it's really useful for moving Gcode files around and that kind of thing. Stops working as soon as I turn on the router control box and VFD, though!

[JAZZCNC]

I wasn't being very serious!

Yes I knew that neil, I wasn't exactly being too serious my self.! . . . And regards your Father experience then I fully it get it.!
To me it comes close or equal to "Can't teach Old Dog new tricks" in terms of irritation.! . . . .I'm so far removed from both it gets me in trouble at times But Experience applied with intelligence along with a good dose of common sense win every time over theory alone in my book.! . . . . But . . . . All my best ideas and achievements started with " In theory it should work" but it does take certain amount of experience to allow the theory to evolve.!! . . . .Chicken and Egg maybe.?

[GEOFFREY]

Yes I knew that neil, I wasn't exactly being too serious my self.! . . . And regards your Father experience then I fully it get it.!
To me it comes close or equal to "Can't teach Old Dog new tricks" in terms of irritation.! . . . .I'm so far removed from both it gets me in trouble at times But Experience applied with intelligence along with a good dose of common sense win every time over theory alone in my book.! . . . . But . . . . All my best ideas and achievements started with " In theory it should work" but it does take certain amount of experience to allow the theory to evolve.!! . . . .Chicken and Egg maybe.?

Sadly I learned long ago that "common sense" is not so common!!! G.