[mike^3]

Hello, I am trying to get the z axis to cold start properly and its acting weird.

I jog the Z axis to the tab, then I enter CS in (Enter Next Command). Once I do this, the Z axis will literally jump 1/4" inch up or down, its random when it does it. If I jog the Z axis anywhere but the tab position and enter CS, it will not move at all.

I can't get the z axis to stay at the tab when referencing home! Therefore I can't use the toolchanger because it won't line up!

Any help would be much appreciated!

Thank you,

[ShovelheadMark]

Hi, I am afraid I will not be much help , trying to muddle my way through a Fadal myself . But I did have a similar problem actually ran the tool changer into a collet. I ended up moving all axis to the coldstart position did the CS command when it was done ,I did not hit start but pulled the power to the machine. Waited a minute or so then reapplied power. After the screen was up I hit start to let it do its boot-up routine then start again and everything was fine. It did it a few weeks later ( this machine does only run a couple days a week ) again , followed same procedure and has not done it ever since. I hope this helps somewhat.

[mflux_gamblej]

very possible that your encoder shook loose and trashed itself. this happened on my vh-65 rotary table, had to replace the encoder. I wrote up a thread on this here on cnczone, which shows how to wire up an inexpensive, modern, usdigital brand encoder.

http://www.cnczone.com/forums/fadal/...it-switch.html

Scroll down a ways and look at the picture of my trashed encoder wheel; if you pay attention you will see that the markings (maroon color) are rubbed off of the wheel.

you need an encoder with the same number of lines, and it has to have an index mark on it. the index mark is what the fadal is looking for when you give the CS command. That's also why you need to align the machine before you CS it, since if you put the axis more than 1 ballscrew rev away from the CS alignment marks, the machine will find the encoder's index marker and the machine will put the CS there exactly 1 or more integer ballscrew revolutions off from the intended (normal) CS position.

Also, be careful about jogging around too much prior to CS'ing the machine, since there ARE NO LIMIT SWITCHES and you will crash the ball nut into the casting on any axis that you overtravel prior to CSing the machine.

its either that - a trashed encoder, or your axis drive board is f*cked up with a bad gain setting, or it's just broken in a different way that needs to be looked at. could also be you z-axis amplifier.

one way to test the boards is to swap them - you can swap 1010 controller boards between x, y, z - just Put them back in the right place when u r done!! and read all the manuals and other info u can find first.

I don't know how to trouble shoot a bad axis amp card. swapping seems like a good first pass there too.


I'd go looking at that z-axis encoder and see if when you pull the cap off of it, that you can see that the encoder wheel is damaged. The wheel will have an annulus with thousands of tiny radial lines which may appear to be almost a solid bar of black or maroon color, the index mark will be a clear annulus but with one bar or 'x' or plus mark at one point on the annulus. If the wheel is damaged at all it must be replaced. A fadal encoder is about $400, a usdigital is about $100 - but isn't a 1:1 swap and you'll have to spend time figuring it out. Might be worth the $400 to just get a direct swap

[mike^3]

Thanks guys, well the z axis has a resolver not an encoder.... I tried the SetZ and that seems to work for now, I tried your version shovel head and it still jumped when I hit ENTER after I put in CS command...

[ShovelheadMark]

Well as I said I am trying to come to terms with this Fadal myself and I just pass on what worked for me on the trial and error basis

[Joe S.]

Try jog to tab, type "setcs" and "seth" then cs.

[ShovelheadMark]

Good that this thread popped up again, as I stated earlier ,I am having similar issues and week before last it got really bad. Called Fadal and they suggested to pull all boards clean connections and reassemble ( careful with static). Which I ended up doing and since everything is working pretty well ( hope I didn't jinx myself here) , just thought I mention that.

[motionman]

You can eliminate this by "clocking" your resolver. Take the cover off the back of the servo motor, loosen the three cam lock fasteners that hold the resolver can down servo motor. Without moving the resolver shaft " it is still connected to the motor via the coupling" rotate the resolver can a few degrees. It takes a bit of playing to get this right. This can also be helpful when after CS the flags don't line up, its a better way of fixing it than just moving the flag.