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Re: homing my rotational axis
« Reply #10 on: June 20, 2008, 09:27:08 PM »
I'm a little confused...Isn't homing, or referencing the A axis just like any other axis ? That is, you only home the machine upon start-up or after a jam or e-stop where Mach has no idea where the axis might be ? If you turn the machine off, then power it up, Mach has no clue where A is in relation to the home switch, above 180 or below.
After the initial homing, couldn't you just return to A0 instead of re homing/referencing ?
What am I missing ?
RC
 
« Last Edit: June 21, 2008, 11:23:48 AM by Overloaded »

Offline poppabear

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Re: homing my rotational axis
« Reply #11 on: June 20, 2008, 09:31:38 PM »
I will let him discribe the issue that he is concerned with, I suspect it has to do with back lash, and he want to reset each time for accuracy.

scott
Commercial Mach3 & Mach 4, Design/Build/Retrofit CNC and Industrial machines.
http://www.ss-systems-llc.com/
Re: homing my rotational axis
« Reply #12 on: June 20, 2008, 09:34:46 PM »
that makes sense.....

You DO see where I'm coming from ?   This script for homing only works if the axis is homed already.........
Maybe it should be called "Return to Zeros" instead.
« Last Edit: June 20, 2008, 11:18:07 PM by Overloaded »

Offline poppabear

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Re: homing my rotational axis
« Reply #13 on: June 21, 2008, 09:55:22 AM »
no, It works EVERY TIME you push the homing button!!

It doesnt matter to Mach if it is homed already or not, ANY time you hit the Home/Home all button, Mach will go to the home switches again in the order that is described in your home button, and RE-Home the machine again, meaning that if you have it set to "Auto Zero", it will reset Machine Coor. to "0" for that axis.

Mach is doesnt assume anything like your already homed, it just does what the VB Dobutton call tells it to.

scott
Commercial Mach3 & Mach 4, Design/Build/Retrofit CNC and Industrial machines.
http://www.ss-systems-llc.com/

Offline Hood

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Re: homing my rotational axis
« Reply #14 on: June 21, 2008, 10:25:06 AM »
Quote
NOTE2: You can use this code to also do the SAME with your X, Y, and Z axis as well, so when you hit "Home All" each Axis will Haul-Ass to some predifined point (in machine coordinates), that is just short of your Home switches, it will then switch to "Homing Mode" and sneek the rest of the way in.

First thing I must say is I am a rank learner when it comes to VB so I am probably wrong. However would that not be a bit dangerous to put that in a Ref All button?
If you switch on Mach and press the Ref All button its going to zoom off on the Z to a predetermined point, only problem is Mach doesnt know where that point is because its not been homed. I can see it being fine for a A Axis as if it overshoots no damage is done but X Y and Z could wreck the ballscrews etc.
 Might be an idea to do an "if" looking at the Referenced LEDs and if lit then do it that way if not then do a normal reference.

Hood
Re: homing my rotational axis
« Reply #15 on: June 21, 2008, 12:03:24 PM »
Hey wait a minute...I"M the rank amateur here ! :D :D Thanks Hood, that's part of what I'm talking about.
I put the script in for simulation and can't get it to work quite right. I emulated a home switch for A, the dro goes to 5 then instantly goes to 0. Like it homes and resets the dro to 0 at that point. I set the home speed to 5% just to see it creep and it is still instantaneous..5 to 0.
Still tinkering though.....

 
« Last Edit: June 23, 2008, 02:52:07 PM by Overloaded »

Offline poppabear

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Re: homing my rotational axis
« Reply #16 on: June 21, 2008, 12:36:01 PM »
Hood:

Tick "Persistant DROs" under General config. That way (Unless you manually move the machine while the control is off), its last position will be the position it comes up in. I dont move my machine other than Mach, so it is a non-issue.

Overloaded:

You are in simulation mode, thus the jump to instant Zero, on a hooked up machine it does like it says, at least on my machine it does.......
ALSO if your A Home pin is NOT enabled will also cause it to jump to instant 0 home.

Further: If you dont like the code or the idea the code represents for a users question then don't use it. Not complaining here, I just offered a solution to a users question, and noted other options that are available, so he could appreciate the many ways in which Mach can be customized to suite a perticular users situation. The Solution my not be something you would do on your machine, or something you would even recommend. But, His machine and current question, appeared to me to warrent the solution I posted. I am sure there are other ways to do it, and by all means, please feel free to post yours. I think anyone with any other ways to answer his quesiton should post thier ideas as well. Then we can look at how others would do it, and ALL learn something in the process.

scott
Commercial Mach3 & Mach 4, Design/Build/Retrofit CNC and Industrial machines.
http://www.ss-systems-llc.com/
Re: homing my rotational axis
« Reply #17 on: June 21, 2008, 12:41:33 PM »
It doesnt matter,

the code below it uses the ABS (Absoute value function), so you can put it in what ever order makes your heart happy............

Scott
« Last Edit: June 21, 2008, 12:47:30 PM by poppabear »
Re: homing my rotational axis
« Reply #18 on: June 21, 2008, 12:48:14 PM »
OH NO Scott...don't get me wrong. I really appreciate what you do and am just trying to learn as we go along.
I was not meaning to HACK on ya at all. I am in awe of what you do.
I'll just lay low and watch, maybe just stick to what I am barely comfortable with.
Sorry if I offended you.
Regards, RC

Offline poppabear

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Re: homing my rotational axis
« Reply #19 on: June 21, 2008, 12:48:52 PM »
opps...........

sorry OVL, stepped in your post below some how, dont know how I did that............

but:

It doesnt matter,

the code below it uses the ABS (Absoute value function), so you can put it in what ever order makes your heart happy............

Scott
Commercial Mach3 & Mach 4, Design/Build/Retrofit CNC and Industrial machines.
http://www.ss-systems-llc.com/