CNC milling with open source software • Hacker News Board

Re: CNC milling with open source software

#131

Post by onmai-xyz » Mon, Jan 21, 2019, 7:17 AM UTC

lvh wrote: post #129

onmai-xyz wrote: post #48

Earlier quoted context omitted.

A good G-Code variant would roll up the un-rolled loops and separate the geometry data from the tool config data. This is what the view of a CAM IDE presents, G-Code source can be structured the same. If you change the semantics on some of the syntax you get lexically scoped blocks, macro-b subsystem which has existed for decades needs to be fully utilized for this to happen. A fully implemented system would provide…

Eventually, something actuates a servo, and servos don’t understand iteration. Do you agree eventually something with g-codes level of detail must exist (even if it’s just unspecified internal commands)? If so, do you agree you’re just advocating for that layer to be part of the machine?

Speaking from user space that has G65 macro-b option, not machine tool builder (sudo) space.

>I think of G-code as ASM.

>Eventually, something actuates a servo, and servos don’t understand iteration.

I think of it more as an intermediate language. Interpreted on the CNC control and JIT compiled to whatever the RT system needs for servo control.

>Do you agree eventually something with g-codes level of detail must exist (even if it’s just unspecified internal commands)?

It does exist and a strict subset with enough primitives to bootstrap an application VM should continue to exist.

>If so, do you agree you’re just advocating for that layer to be part of the machine?

I am advocating for a DSL one layer up to be part of the CNC machine with support offline in say the JVM.

I want to answer this question, “how do we deploy MBE?” https://www.nist.gov/news-events/events/2019/04/model-based-...

The answer needs to be a single digital file that can render real parts and virtual parts. Why not?

Re: CNC milling with open source software

#132

Post by grawprog » Tue, Jan 22, 2019, 11:24 PM UTC

onmai-xyz wrote: post #126

grawprog wrote: post #34

Earlier quoted context omitted.

The g-code variant my machines use contains most of the control structures of modern programming languages. It has variables, comparisons, loops, subroutines, the codes are all fairly straight forward and honestly a lot of g-code is produced automatically with CAM software rather than being written manually these days. It's a simple language, you don't have to memorize the codes and you end up memorizing the few you…

Have you been able to arrive at any clear repeatable structure in your macro programming, or is it just ad-hoc make it fit for this job and this machine? Asking, because I am trying to level up cnc programming to "normal" programming.

Not so much no. About the closest i come is reusing the same program for pieces that are identical. This rarely happens.

The cam software i use does come with a few handy baked in things. Stuff like automatically lowering the feedrate for corners under a certain radius or for setting up z-level ramps.

There's a couple i can think of being handy. Functions for automatically decreasing feedrates at certain axis loads or horsepowers would be nice.

I think it would come down to something more like a handy library of functions for little things like that rather than anything really repeatable. Even that would likely be specific to whatever machine you use though.

Re: CNC milling with open source software

#133

Post by nadavami » Mon, Jan 28, 2019, 6:13 PM UTC

gangstead wrote: post #21

nadavami wrote: post #8

Earlier quoted context omitted.

I've been using a 3018 CNC with pretty good results. They're fairly inexpensive machines (about $300 I believe) and are decently accurate. I still order boards from China, but for a quick breakout board it's incredibly handy! I also decided to get a 5W laser which is also pretty fun to engrave with. I'm planning on writing a series of blog posts about it if you're interested! As a last note, if you like tinkering, th…

I'm definitely interested. I got into 3D printers and CNC machines at about the same time last year. I figured out the 3D printer right away and quickly went from printing out things on thingiverse to doing my own designs and outgrowing my printer and getting a fancier one. While I've done about 250 print jobs in just under a year on my 3D printers after 8 months with the CNC I've cut two things. I got an entry level…

I've started adding some posts about the CNC upgrades here: https://nadav.ca/2019/01/18/list-of-3018-cnc-upgrades/

It's still a little bare, but I'm hoping to add more detail as I can. Feedback is also very much appreciated!