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Fadal tapping speed .1 or .2 ?

camhead420

Cast Iron
Joined
Nov 22, 2019
Hello to all,

I had the subject come up of why I use S200.2 for tapping instead of S200.1.
It has been so long I actually could not remember, getting old I guess.:codger:
What is everyone doing out there?

Thanks!
 
S200m3 will auto shift into low gear so there really is no need to use .1, S200.2 will keep the spindle drive in high gear, I usually use it for tapping small holes in hard materials were torque consideration is not an issue.

I feel ya on the old part..
 
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I have no idea of the actual reason they recommend that. In practice it doesn't seem to matter.

Though I have a theory.. Say you are running a big tap. 5\8" or something. If that tap stops cutting due to any number of reasons, in high gear, it'll probably stall out.

In low gear there is enough torque to break the tap, and enough torque to break a bigger tap can potentially cause other issues, like moving your vise or ripping the part out of your fixture.

There is a lot of torque there in low gear, its not chicken feed. 15hp at 100% duty cycle, geared down 2:1. Do the math.
 
Bob,
What method of tapping on a fadal is your preference rigid or tapping head?
We had trouble recently with 1/4-28 threads being oversized.
Rigid seemed to be causing it.
 
I know you asked Bob but I used to tap tens of thousands of holes in aluminum with a Fadal. Tapping heads are worlds better, and faster when doing production. They are way easier on the spindle drive since it isn't reversing all the time and soooooooooooo much faster. A Fadal with a small Tapmatic running at 3k will tap pretty damn well.
 
On my VMC 15, I use .1, and rigid tapping. It doesn't have a gearbox, and for whatever reason, it isn't happy rigid tapping in .2. Also, someone had changed the spindle gains before I got the machine, and it wouldn't rigid tap at all. I set them back to the values on the sticker in the control pendant, and it taps just fine now. Though I don't tap very fast with it. On the work it does, tapping cycle time isn't critical.
 
I think that if you are using a tapping cycle where you need to reverse the spindle, keeping it in high range with the .2, the spindle will reverse quicker.

If you have a lot of smaller holes to tap, I am all in with using a tapping head. Very fast and less wear on everything. Almost a fast as drill the hole.

I don't have rigid tap on my machine so not many choices.

Rick
 
Thanks for the input. I typed tapping head when I meant tension/compression holder. My bad.
I do remember using those on an old boss 8, really fast. This 3016 Fadal may need looked at if doing rigid tapping is
making bad threads. 1/4-28 always has been a problem though.
 
Thanks for the input. I typed tapping head when I meant tension/compression holder. My bad.
I do remember using those on an old boss 8, really fast. This 3016 Fadal may need looked at if doing rigid tapping is
making bad threads. 1/4-28 always has been a problem though.

Try tweaking the Q value in the rigid tap line, might help.
 
We use format 2, so I could try tweaking the feed I suppose.
Want I ended up doing to fix it was run G84 S300 F10.7,
made nice threads.
 
I have a 15xt and usually use MO3 S500 and never had a problem. I have another question about our 6030 gearbox. What is the max speed in low range?
Is there a minimum RPM in high range?
 
On my VMC 15, I use .1, and rigid tapping. It doesn't have a gearbox, and for whatever reason, it isn't happy rigid tapping in .2. Also, someone had changed the spindle gains before I got the machine, and it wouldn't rigid tap at all. I set them back to the values on the sticker in the control pendant, and it taps just fine now. Though I don't tap very fast with it. On the work it does, tapping cycle time isn't critical.
Fadal VMC15 does not have a 2 speed gearbox,
 
The spindle encoder is on the motor, not the spindle itself. In theory you should get 4x better resolution in low gear vs high gear. In my mind that should make it easier for the spindle and z feed to stay in sync. I think. Maybe.
 
I tap using xxx.2

The machine (20/30hp VHT motor) hasn't had a low speed belt in years. So by default it's gong to be xxx.2
 
I have a 15xt and usually use MO3 S500 and never had a problem. I have another question about our 6030 gearbox. What is the max speed in low range?
Is there a minimum RPM in high range?

In low range 2500rpm is max speed (not necessarily what the spindle is actually doing if you don't have an encoder)

Lower rpm in high gear?
That would take you 2 minutes to find out. Manually input lower and lower speeds until it either faults out, or you realise there's no practical point in a very low speed in high gear.
I'd venture a guess, less then 8rpm. I know mine will run at 8rpm in high gear. Started a program where the programmed speed was 8rpm. And that's what it did. I really wanted 800, finger error.
 
The high/low Fadal drive ratio is 2-1 in low range and 1-2 in high range.
Tapping at 1000 rpm in low range means the motor is turning at 2000 rpm, high range the motor only turns 500 rpm to output 1000 rpm at the spindle.
The machine auto range shifts differently in the tapping cycle, 750 rpm and below is automatically set to low range, 751-3000 is high range.
The forced range code of .1 or .2 is not needed unless you want to override.

The machine should be smoother and more efficient in high range, much less inertia to reverse in high range.
 








 
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