Hi!

My first post on this forum. But been reading for quite some time, and this forum got a lot of useful information for a n00b like me

First off. sorry for my bad english


So the story goes -> built a mach 3 cnc mill and got tierd of it.. Came across a haas 1996 vf-2 for a reasonable price, and ended up buying and restoring it.
One thing i really loved about the mach 3 setup was the probe stuff. It made it so simple to probe a bore or position the rotary table and set work offsets, so i was really missing the probe on the haas.
Since i bought the machine for like 6000$ USD including the 4th axsis rotary table, you get that the budget is not to high, as it`s more of a hobby machine for me now, then anything else.

I did look into the reneshaw probing systems and stuff, and that would kinda blow my whole "tooling budget". So i was looking for a cheaper option.

There`s not a problem finding useful information about the reneshaw stuff, but the DIY stuff is much harder to find on these machines, since they are mostly in production compared to mach3 hobby machines.


So here goes:

Fist off, i had to figure out the SKIP signal stuff. Since i did not know anything about the skip function, i had to collect the information here and there. So for you out there that`s in the same boat as me, and know nothing about the SKIP , I`ll quickly explain.
The SKIP signal is an input signal used i combination with some Gcodes, to stop the machine when the SKIP signal is broken or recived (depending on inverted signal or not)
So the Gcode: G54 G36 X10.0 F50 will move the probe to X10 or stop the probe if it touch something. It then automatically ZERO your G54 at this spot.


So what I did was to find two wires, connect them to the SKIP input pins on the I/O board and short the wires together, when watching the SKIP input

Here you can see where to connect the pins. I just stole the "connector" from an old CPU computer fan i had. It fits right on there
It`s marked 1070 P47 on the I/O board, on the backside of the connector not shown in the pic, it`s says "skip"
Attachment 334726

Watching the skip-signal change when shorting the wires together - you will find this under diagnostics -> descrete inputs
Attachment 334724

You can invert the skip signal, depending on what style probe you got.
Attachment 334728

I Just bought a cheap one off ebay called TP-1000 . I liked the design of the adjusting screws on this one, so that`s my only reason for buing it compared to anyother I found out there.
Attachment 334730

Next step was to wire up the probe. I simply did that by using some "ev1 injector connectors" i had laying around the shop. My plan was to use a minijack, but could not find one, and did not feel like going to the store
Attachment 334732
Attachment 334734

Almost eveywhere I was reading regarding probe stuff, Macros where mentioned. So I was a bit confued whether or not i needed the macro option installed to get this to work properly. I dont have the macro option installed on my machine.

So far so good, I manage to use the G-codes without any Macros, alteast to do the most common probing stuff like bore center and simple work offsets.


Here`s a small video showing the probe in action:
https://youtu.be/tLi1rmDhHI4


And I`ll end this with some code exampels:

G31 (stores the probed point to memory, used with M75)
G36 Automatic work offset measurement
G37 Automatic tool length offset measurement
G136 is verry useful. Uses the value stored with G31 M75, and the value meassured with G136, and dived`s that in two. to find the center point.

SO to find center of X in a bore and store that as G54 (I run Metric on my machine, so just a note if the speeds looks a bit off):

%
o00002
G91
G54

G31 X30. F1000. (runs in x axis and stop when probe touched something, or 30mm is reached)
G01 X-1. F200. (goes back to clear the workpice befor a slow measurement is done)
G31 X1.5 F20. M75 (does the measurement at slow speed, and stores the meassured X value in the memory to be used for later)
G01 X-1. F200. (clear workpice again)
;
;
G31 X-60. F1000. (rapids over to the other side of the bore, and stops when probe touches)
G01 X1. F200. (clear workpice)
G136 X-1.5 F20. (slowly meassure workpice and automatically set the work offset to center of the two sides meassured, using the M75 stored value from the opposite side)
G01 X1.0 F200. (Clear workpice)
G90;
G01 X0. F500. ( travel to center of what`s just meassured)
M30
%

Repeat the process for the Y axsis if you want to find the center of a bore/pocket/slot

For finding an edge or corner of the workpice, use G36, as this will set the work offset directly when the probe touch. Remeber to set the stylus offset under settings 59-62.
Attachment 334766

Hope some will find this usefull

Sorry for all the photos beeing flipped sideways allmost breaking your neck