[OlfCNC]

"and on the arduino grbl.. no. just no. i know its fun to slam mach3, but short of the cv bug which makes it unreliable, it has some of the best high speed contouring ive seen... better than what ive seen from the lower end vmc's"

You mean the bug which overrides your decceleration settings is the best high speed contouring algorithm, it is fast because it is broken and for the same reason it is unreliable.
I have to tell you that for example the UCCNC does that type of job far better and I know what tolerances I allow for my jobs unlike with M3 where I could only guess.

[Jon.N.CNC]

i change my velocity and acceleration alot, at least in the early days of the machine. (not sure why youd want to change it per job)

for error checking, it should just be able to find the first or last entry and just use that. although that could cause some of your changes to not be recognised if you get it in the wrong order. using both at random in one session is quite bad (creating them is quite bad to begin with of course)

tuning acceleration for material is important for tool life and finish I find.

Indeed, I got the feel it was constantly refering to xml during all given moves for perameters, only reason I can think why it would use flip between duplicated settings.

[ihavenofish]

the cv bug doesnt show up in every program.. only the ones that matter :P

when it doesnt stall, it is great.

100ipm, 0.1G, starts with g64 off, then gets turned on.
has finish youd swear was already sanded to 320 grit:

[ihavenofish]

tuning acceleration for material is important for tool life and finish I find.

Indeed, I got the feel it was constantly refering to xml during all given moves for perameters, only reason I can think why it would use flip between duplicated settings.

mach3 does not check the xml after startup that im aware (unless you change a setting to write to it). i wonder if this just coincides with some other velocity/acceleration bug (which we know it has).

[Jon.N.CNC]

you know if you tune the acc and val in Mach3 to a big 3D file you only have to do it one time, do you do a restart after changing settings.

Mach4 does not have a .xml and changing settings in Mach 4 is fine it builds a new .ini backup on every restart, so if it's out you just go back one back up and I have never had to do that even when I was tuning it what was changing the acc and vel a lot. and if you change major settings in Mach 4 you can just delete the built files and on restart it rebuilds them to what you changed to, every new ESS plug I do this and I don't have and problem with files going bad at all.

the GRBL trajectory planer is a lot different to the one Mach use's it's bananas to tomatoes. snap, crackle and pop.

.ini .xml little difrence really. It should still error check. And why does it build a new ini backup on restart if nothing altered.

[RCaffin]

Hi Jon

> manually opening xml in notepad each time and correcting duplications which were frequent
But notepad displays all the contents as one long text string. To the best of my knowledge, it does not sort the XML lines out. So HOW do you make any good sense out of it in finite time?

How do you find duplications in that long text string? Notepad is not renown for having any extensive facilities. Don't get me wrong: I use Notepad a lot, every day.

Pete's XML Editor at least makes a tolerable display, but I don't think it can find duplicates.

Cheers
Roger

[ihavenofish]

Hi Jon

> manually opening xml in notepad each time and correcting duplications which were frequent
But notepad displays all the contents as one long text string. To the best of my knowledge, it does not sort the XML lines out. So HOW do you make any good sense out of it in finite time?

How do you find duplications in that long text string? Notepad is not renown for having any extensive facilities. Don't get me wrong: I use Notepad a lot, every day.

Pete's XML Editor at least makes a tolerable display, but I don't think it can find duplicates.

Cheers
Roger

step 1... word wrap.

if that fails go to step 2

step 2... who uses notepad? seriously, is this 1986? :P

[Jon.N.CNC]

mach3 does not check the xml after startup that im aware (unless you change a setting to write to it). i wonder if this just coincides with some other velocity/acceleration bug (which we know it has).

Nope, it made duplicate entries frequently in xml plain to see. And would use one in one direction and another in opposite and not consistently. Not an accel bug

[ihavenofish]

Nope, it made duplicate entries frequently in xml plain to see. And would use one in one direction and another in opposite and not consistently. Not an accel bug

peculiar. my last mach3 machine caught fire and melted the hd, so i cant even go look to check whats in there. my new one is linuxcnc

[Jon.N.CNC]

step 1... word wrap.

if that fails go to step 2

step 2... who uses notepad? seriously, is this 1986? :P

lol I used to write entire websites in notepad. Read it once and became occustom to its format I suppose, wasn't hard to spot duplicate entries.

Or you could use 'find' I suppose.

You obviously Think I'm talking bs. I welcome you to try it yourself. Enter a duplication manually and watch your machine turn schizophrenic, and believe me I didn't just do this for fun. It was a complete ball ache.

[Jon.N.CNC]

peculiar. my last mach3 machine caught fire and melted the hd, so i cant even go look to check whats in there. my new one is linuxcnc

Lol!

[ihavenofish]

Lol!

cant blame that on mach3 sadly.

[RCaffin]

To the best of my knowledge, Mach3 reads the XML file at the start and writes a new one when it exits.
It can also write a new one when you 'Save Settings', which is a very smart thing to do when you are using gang tooling on a lathe and have spent an hour creating the tool table to within 10 microns. And i can come back the next day, check the Master Tool zero, and run.

-------

Do some systems REALLY run code compressors which can skip over fine details of your design (gcode)? Does that mean that if I want to put a 0.1 degree taper between sections, the system might distort that design? The mind boggles! That is not a Computer Numerically Controlled machine; that's a very rough crude amateur hack! Appalling! But perhaps I misunderstand?

I can use Mach3 to make tapers on the lathe that match an ER collet or a Morse Taper or a drill chuck arbor to a precision that no manual machine could match without days of setting up. All I do is specify the taper in degrees. And I can mill circles to almost lathe accuracy with Mach3.

Deviation control - bah, humbug. Do or not do; there is no try.

Cheers
Roger

[OlfCNC]

Do some systems REALLY run code compressors which can skip over fine details of your design (gcode)? Does that mean that if I want to put a 0.1 degree taper between sections, the system might distort that design? The mind boggles! That is not a Computer Numerically Controlled machine; that's a very rough crude amateur hack! Appalling! But perhaps I misunderstand?

Yes, in G64 probably all systems compress codes. If path optimisation is what you mean by "code compression".
Advanced trajectory algorithms optimising for path deviation, you set what position error you allow as a maximum on the path and the tool will run on an optimised fastest path creating not larger error than what you setup, but optimising to run the fastest.

Mach3 does the same, but it does not optimise on deviation, it's just cutting off paths based on some rate numbers settings called CV control and based on your acceleration and velocity settings and the actual programmed feedrate.

This is why I say it does not have a good trajectory planner, because you can't set the max. path deviation, so you can't control the workpiece tolerances properly.

Ofcourse you can go back to G61 mode, but 3D works will be pretty slow then.

[ihavenofish]

compression is a holdover from old industrial controls. back when they could only process a few blocks a second. it wa sa way of optimising sloppy code from early cadcam systems. these days we can process hundreds if not thousands and even freebie cadcam software creates very clean code, so compression really should be OFF by default in linuxcnc.

ill also note that NOWHERE in the docs was there a reference to this being on if you dont explicitely type it. the only reason i ever found out was samco mentioning it off hand.

[109jb]

what level of computer expertise do you have? what seems simple to you, may not be for others. the typical mach3 customer is an entry level machine user, not a machine integrator or programmer. telling someone to open a hal file and edit it is far beyond most people here. the wizards are only partially workable usually and laid out in not the most intuitive manner (somethings actually busted in the most recent one forcing you to edit the text files). mach3 could certainly be called restrictive, but its pretty point and shoot to set up i find, especially when supplied with preconfigured xml files by the break out card makers.

With the setup wizard, a parallel port stepper machine can be set up without the user ever having to open a hall file. That is my point. The posts here make it sound as if a computer science degree is needed to set up any LinuxCNC machine. That just isn't true. My first experience with Linux was when i set up my machine using the live CD.i have also never had to manually edit my half file. I let the wizard take care of it

Sent from my Z958 using Tapatalk

[109jb]

OP just stay with M3 see how it goes if it's **** try something else.
Linuxcnc is easy to set up if you have one of the boards in the drop down yes I had it running in an hour with a G540, if the board is not there it is hard unless you find a non Linux a hole to help, some of the people on the Linux forum are well they need a attitude adjustment, what stop people from using it.
the other type of controllers out there are depending on what you wont to do are better than Mach 3 in some ways, are they better than Mach4 can't say it's not finished.

I use a program that has a 6th order planner built into it, is it better than the rest of the hobby controls don't know, but it's better than Mach3.

ihavenofish nail driven in on that point

I totally disagree. As I said, I set up mine with a Chinese breakout board in an hour. You just need to know the parallel port pin numbers for the breakout board. Which is something you need with Mach 3 too.

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[ihavenofish]

With the setup wizard, a parallel port stepper machine can be set up without the user ever having to open a hall file. That is my point.

in the the current build the wizard is broken and you DO need to touch the text files to reset max/min acceleration and velocities. THAT is my point. when you get it done, it works lovely (2.7 and up anyway, before the new trajectory planner is was borderline useless). but if youre green, it may or may not go smooth and can be very confusing.

usability is always in the eye of the beholder. you need to look through someone elses eyes to really see whats going on.

[daniellyall]

With the setup wizard, a parallel port stepper machine can be set up without the user ever having to open a hall file. yer that true what about everything else, not everyone has a computer with a pp anymore so how do you set up a Ethernet board that is not all ready in the system, like what the novakon guys are doing ????


Jon.N.CNC I put it wrong it wights a back up when you do changes to the config on close, what it should do M3 does it, just tested your ideas no problem found. M 4 is so different to M3 it's not funny it has a good system error logging done by the external controller and internal, you can do it when it's running. and if there is a major problem it will crash hard in software to the problem is fixed

109jb you are correct when it comes to what is there already there, there are a quite a few boards in the wizard and it is easy but only with what's there. the boys doing the conversion of novakon machine are having a lot of fun not, but there are a couple nice Linux boys helping there so it's not to bad but it is hard work for the guys who don't know linux

[RCaffin]

compression is a holdover from old industrial controls. back when they could only process a few blocks a second. it wa sa way of optimising sloppy code from early cadcam systems. these days we can process hundreds if not thousands

I thought so.
Except that the ESS (just as an example) can output pulses for an exact profile to a timing resolution better than 10 microseconds. (I forget the exact value.) This is a far cry from dinosaur systems found on older machines - no matter what fancy front panels they have.

As for the architecture of the Trajectory Planner - that is a different matter. Mach3 uses position, velocity and acceleration. That works fine for me, but I am not cutting at 400 ipm, and my machine is quite robust. So I do not hesitate to state that Mach3 works very well for me.

I know Art Fenerty has been working on a more refined TP, allowing for 'jerk' (rate of change of acceleration) and possibly even higher order term(s). He is also trying to do something like Bezier curves at the corners, which is really rather cute. I gather it is starting to work. But the maths is heavy, and of course one MUST get it right for it to be usable. I dare say he will.

Accuracy is an interesting idea. Early CNCs were built with masses of chips on big PCBs, and were a bit crude. Calculations done in a modern PC-based CNC system are often done in double-precision. That has so many more decimal places than you could ever imagine: accuracy down to the size of an electron. Gigabyte disk drives and gigabyte memories (and gigaHertz clock speeds) have replaced punched paper tape. Deviation control and code compression are now obsolete concepts.

Cheers
Roger