Fanuc OM tapping prolem

[glovebox20]

Hello

The shop that I work at has a Komo V144 mill with a Fanuc OM controller. Long story short, a board went bad and we they replaced it, and we lost the parameters. We have everything pretty much back to normal except the tap cycle. Originally, we needed to specify M84 to activate the rigid tap cycle but now it dose not work. Could it be that the parameter the specify rigid tap (No. 256?) is not set right, or is there something else we need to look in to. Right now the parameter is set to 0. If I recall right, M29 on this machine lowers the tool pocket for the tool changer (M28 brings it up). Just wondering what you guys think.

I also would like to know where I can find the info for the Variable # and what they do (ex #5043 = Z axis absolute position). I would like to find out where the current tool in spindle is stored so I can relate to it in my macro program for the tool changer.

Thanks

gloveox20

[sinha_nsit]

G84 can be used in standard mode or rigid mode, depending on a parameter. I do not know parameters for your control. The other method for rigid mode is to cammand an M-code (M29 on 0i).
Look into Operator's Manual (Custom Macro B section) for information about system variables.

[glovebox20]

Thanks for the reply. I would like to keep the tap cycle the same as before so we don't have to change the the post on the cam system, but that might be easier.

I'll look into it when I get a chance.

[gbowne1]

For My 0M-C, I do a lot of 3/8"-16 and 1/4"-20 tapping in aluminum (2024, 7075, 6061, 6013, etc) and some steels (4130, 4140, 4340, 1018, etc). I do other sizes too but.. would like to have macro programs for some that I do because some I do so much of.

I have the Macro Cassette C A02B-0091-C115 with the board A20B-1002-0330/02A inside it. I wanted a bigger size but couldnt find a bigger cassette on ebay with the right part number.

I use a Bilz CAT40 tap holder and a few collets.

Anyone want to help me write a few macros? or have a macro programmer?

Greg

[The Engine Guy]

For what it`s worth here is a sample of tapping code as used on my Fanuc 0M-Mate (F) control.
Machine is a 1989 BP 412 not rigged for rigid tapping
Tool holder is standard BT40 using Bilz type tap holders that is "tension" only, did around 300 holes of different sizes yesterday alone!!!

2 tapped holes 8mm x 1.25mm pitch 17mm deep

(8MM SPIRAL FLUTE TAP)
G90X34.343Y-0.7S300M3
G43Z5.0H8M8
Z2.0
G98G84R2.0Z-19.188F375.
G80
Z5.0
X-34.357
Z2.0
G98G84R2.0Z-19.188F375.
G80
Z5.0

[gbowne1]

Are you happy with the Bilz holders? I have been.

I see you used G90, G98 and G84.. and then feed rate after the line.
You also used G80 and G43.

What type taps do you use? Mine are G3/H3. I don't do metric tapping yet, but have done some for screw sizes.

Greg

[sinha_nsit]

Unless rigid tapping is being done, floating tap holders would have to be used.
With G94, F is in feed per minute (rpm x pitch).
Wth G95, it is in feed per revolution (i.e., equal to thread pitch)

[fanuc-support.c]

Parameter 256 needs to be 84. The default M code from Fanuc is M29. But you will have problems with this as the machine tool builder has set M29 for something else in the PMC. This will take presidence.

To use G84 for Rigid tapping set param 76#3.

[gbowne1]

I've normally been tapping aluminum at about 70 to 80 sfm on G3 / H3 class taps. It's not blind hole tapping. they are through holes.. most of it is for recessed 1/4-20 SHCS. I still try and get accurate 75% threads at the minimum. I've run some basic experiments on this.

RPM I'm not sure.. about 60 to 80rpm I would guess.

Greg

[glovebox20]

Originally Posted by fanuc-support.c Parameter 256 needs to be 84. The default M code from Fanuc is M29. But you will have problems with this as the machine tool builder has set M29 for something else in the PMC. This will take presidence. To use G84 for Rigid tapping set param 76#3.

Thanks for your help guys. Unfortunately the problem is deeper than this. When I use a M29 (No. 256=29), the machine give me a #205 alarm (Rigid Mode DI signal off. Check PMC Ladder Diagram to find the reason the DI singal (DGNG061.1) is not turned on). When I use the original M84 (No. 256=84) it give me a #403 servo alarm: VRDY OFF followed by a #437 alarm: Z axis DGTL Param witch I can't clear unless I turn the machine off. When i was in MDI mode, I used M28/M29 (tool pot up/down according to MTB manual) nothing happen. I know this worked before we replaced the boards. So I'm guessing the PMC ladder is not set to original spec.

Dose any know where I can find Information on how to read the PMC ladders?

Thanks again

[stevo1]

You need to know what model Om control you have. The earlier model A and B you can not display the ladder at the control. Model C and D you will be able to view the ladder.

If the MTB set the ladder to use M29 for something other then "rigid tap" mode then you will not be able to set this specifc code for rigid tap.

What was #256 set to before (originally)? Was anything else changed? Did you have to re-enter your option parameters? It could have been that you deactivated rigid tapping. I am not sure it is that because you will typically get a “improper code” alarm.

Can you post your code that you are using to try and tap?

Stevo

[glovebox20]

I believe its a Fanuc OM-A from the early 90's (1994?) It has "A" type tool offsets. It dose have macros list on the offset menu, But I believe it's macro A, not "B"

Here is the G-codes we used before the boards went bad

G30 G91 G0 Z0 M19
T3 M6 (1/4-20 tap)
G17 G40 G80
M8
G90 G54 G0 X1. Y1. S500 M3
G43 Z1. H3 T4
S500 M84
G84 X1.Y1. Z-.75 R.1 F25.
G80
M9
G30 G91 G0 Z0 M19
M30

The machine runs the program just fine without the S500 M84 Line but the spindle is not timed to the Z axis. If you had a compression Tap holder, you could problem get it to work. Right now, the machine alarms out with a #403 alarm followed by a #437 alarm using the M84 code and a #205 alarm with the M29 code.