Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: JonOfArc on January 15, 2018, 11:39:09 AM

Title: Lathe toolchanger macro issues
Post by: JonOfArc on January 15, 2018, 11:39:09 AM
Hi all,

I am currently retrofitting an old Boxford 125tcl I bought off Ebay.

The seller did provide me with a macro for the "lock back to pawl type" toolchanger.
However, it seems to be totally useless.

Here are some issues:
1) Wrong tool: Say after I started Mach and my machine and I issue an M6 T101 in MDI, the active tool number changes from 0 to 1, without the turret moving.
It seems the machine does not remember the last tool it was on.
2) It only works every 2nd time: Ok, lets say I manually move the A-Axis (which is used for the stepper at the turret) ,locked it into postition, and then issue an M6 with any number (say M6 T303), the machine says: "Moving turret to save postition", but absolutely no movement is carried out.
If I then E-Stop or Reset the machine in any way and issue the same line of code again, it will move to a safe position, and might even change to the correct tool.
3) Safe position: When the machine does move to it's toolchanging position, it moves to a completely akward place: First it moves to a random Z+ position (away from the chuck), but then it moves to an X- position, below the centerline of the chuck...... and I cannot figure out how to change the position. It would be nice if the machine would just move to the home switches and do its tool change there....

I have attached the two macros to this message. Could anyone perhaps take a look at them and tell me whats wrong?

Also, are there any public toolchanger macros for this kind of turret which can easily be modified to suit my needs?

Any help would be highly appreciated!  :)

Thank you and kind regards,

Jon
Title: Re: Lathe toolchanger macro issues
Post by: JonOfArc on January 25, 2018, 02:54:01 PM
Nobody got any suggestions?
My lathe would be finished if I wiped out this problem...
I am getting pretty frustrated after spending so much money with retrofitting and then beeing held up by a simple macro...
Title: Re: Lathe toolchanger macro issues
Post by: Cartierusm on January 28, 2018, 01:19:37 AM
What kind of motion control board are you using and what is controlling the tool changer, a PLC?
Title: Re: Lathe toolchanger macro issues
Post by: JonOfArc on January 28, 2018, 04:47:27 AM
What kind of motion control board are you using and what is controlling the tool changer, a PLC?

The common chinese 5 axis BOB from ebay:
https://www.ebay.com/itm/1pcs-5-Axis-CNC-Breakout-Board-For-Stepper-Driver-Controller-mach3/201414938686?epid=1847551621&hash=item2ee544103e:g:GTkAAOxyBjBTWMPR

This is also used to control the toolchanger, using the A Axis output to control a stepper motor responsible for driving the turret.
Title: Re: Lathe toolchanger macro issues
Post by: Cartierusm on January 28, 2018, 10:58:19 AM
Ah, sorry no idea then.
Title: Re: Lathe toolchanger macro issues
Post by: TPS on January 29, 2018, 02:24:59 AM
Hello Jon,

had a look to the macros, and i am not getting clever of it.

i dont know your toolchanger.

is it something like shown here: https://www.youtube.com/watch?v=lRRlSRWfSqs ?

if you are moving a-axis in Manual mode, is it allways moving ?
where are the home positions of X and Z ?
X and Z directions are like in the Video?
how is the toolchanger satteled/locked after a Change?

excuse my bad english.
Thomas
Title: Re: Lathe toolchanger macro issues
Post by: JonOfArc on January 29, 2018, 05:27:29 AM
Hello Jon,

had a look to the macros, and i am not getting clever of it.

i dont know your toolchanger.

is it something like shown here: https://www.youtube.com/watch?v=lRRlSRWfSqs ?

if you are moving a-axis in Manual mode, is it allways moving ?
where are the home positions of X and Z ?
X and Z directions are like in the Video?
how is the toolchanger satteled/locked after a Change?

excuse my bad english.
Thomas

Hi Thomas,

Incidentally, this IS my lathe.
The video was made by the previous owner.
The axis move normal, both in manual (jog) mode and during a program.
In theory, the machine should behave like this:

1. Issue e.g M06 T101
2. Move home
3. Index the turret to the requested station.
Indexing is done using the A axis in the PLUS direction.
After having moved to the requested station, an A MINUS move is carried out. This forces the turret against a spring loaded pawl, and therefore locking it in the correct position.

In the video, the home switches were removed.
In reality, they are placed shortly before the "hard" limits
In the positive direction, to avoid crashes.
I will add a picture when i get home tonight.

Since I created this topic, I have adapted a script I found on the internet, which is far more easier to understand and formated in a better way.
But because I don't know anything about Virtual Basic, and the last time I wrote a tiny CMD script was when I still went to school, the script also won't work, but it at least does a few correct moves.
I will continue working on it tonight, then I will post it, maybe someone with more experience in programming can tell me what I am doing wrong.

Thanks and best wishes,

Jon


P.s.: Bin aus Österreich, d.h wir können auch gerne auf Deutsch schreiben :)