Hey all you Fanuc 5-axis guys...

[Jeremy Herron@DBS Solutions™]

It has been a while since I have run a Fanuc 5-axis machine, and I am not up on all the new controller features. I have 2 configurations, one head-head, and one table-table. I have been runing Mazaks mainly for the last 5 years, and they use G54.4 and or G43.4, for workpiece error comp (distance from program zero to center of rotation) and TCP respectively. How do the new Fanuc controllers handle the situations?

 

TIA.

[Guest SAIPEM]

G54.2: Dynamic Offset

 

G43.4: TCP

[Joe788]

What kinda machines you getting Jeremy?

[Jeremy Herron@DBS Solutions™]

I have a customer with a OKK KCV 1000 and a smaller OKK VM7. I was just curious. Thanks Guys.

[Guest CNC Apps Guy 1]

G54.4 is WSEC = Work Setting Error Compensation. This is for 5-Axis Error Comp. G54.2 is RTDFO = Rotary Table Dynamic FIxture Offset this is for 3+2 ONLY.

 

G43.4 like he said is TCP = Tool Center Point Control.

 

Both functions work well.

[Jeremy Herron@DBS Solutions™]

Sweet. I knew Mazak was copying Fanuc. I just wanted to make sure. Thanks again.

[Newbeeee™]

^^^from what little I know, if mazak copy anyone they should copy Heidenhain

[JSwistak]

Hey folks...Does this group know of any information about guidelines when using Rotary Table Dynamic Fixture Offsets? We run 6th axis on large horizontal machines with the 2nd rotary sitting on top of the B Axis facing the spindle.

We sometimes get the Dynamic Offsets to work and sometimes not... If we had information about the capabilities and limitations of the G54.2 RTDFO we could plan our programs and setups accordingly. I saw a chapter in the book by Karlo Apro "Secrets of Five Axis Machining" about RTDFO but no guidelines were discussed.

[Guest CNC Apps Guy 1]

RTDFO is for 3+2 ONLY, PERIOD! That's the main guideline you need to be concerned with. If you need simultaneous handled, you must use WSEC. In WSEC, you DO NOT want large numbers either. You're limited to a single digit to the left of the decimal. It's an awesome function, just ask anyone that machines castings but needs to make 5-Axis cuts on them and every part is different. It;s a real time saver. With a probe you can cut setup time from hours to minutes.

 

RTDFO, TCP and WSEC are a functions of the control not really of CAD/CAM or Kinematics. Karlo IIRC devotes most of the book to CAD/CAM and Kinematics. Both are SERIOUSLY important concepts to have a good grasp on before you start looking into and talking about control options. IMHO of course. But, all the functions behave differently under different kinematic condtions, ie. Nutating Head, vs, Tilting Head + Rotary, vs, ROtary On Rotary.Just some more to gnaw on.

[JSwistak]

^{Thanks for your post. I'm not sure what 3+2 is. Three axis plus B and C? Our horizontal machines have a full indexing B axis with the 6th axis as on option- Tsudakoma's that we sit on top of the B. I understand the G54.2 is a function of the control but if we can keep our datum close or on the center of the C axis our chances are better that the Dynamic function will be successful.}

^{The last job we setup had the datum quite far away from the center of the rotary and we could not get the part to machine correctly. I have setup parts where all we had to adjust for in the Fixture offset page was a Z value and the parts ran quite well, indexing the B and C axis'.}

 

^{Thanks again}

[Guest CNC Apps Guy 1]

_{...I'm not sure what 3+2 is.}

_{3+2 is positioning only, meaning you are not cutting X, Y, X, A and B simultaneously or in simpler terrms, none of your rotary axes are involved in the cutting motion, they are just being used for positioning purposes. Another example, you have a Cube with a hole on each of the 5 acessable faces. To cut the holes, you will use positioning or 3+2, NOT 5-Axis. Now lets say you have an impeller... more than likely at the very least on your finishing ops, you are going to be moving ALL axes simultaneously, this is 5-Axis. Hope that clarifies a little better.}

 

_{Our horizontal machines have a full indexing B axis with the 6th axis as on option- Tsudakoma's that we sit on top of the B.}

_{"Full indexing" is a bit of an oxy-moron. It's either full 4th/5th, or it's indexing. "Full" can index too, "indexing" cannot go full. Hope that makes sense.}

 

_{I understand the G54.2 is a function of the control but if we can keep our datum close or on the center of the C axis our chances are better that the Dynamic function will be successful. The last job we setup had the datum quite far away from the center of the rotary and we could not get the part to machine correctly. I have setup parts where all we had to adjust for in the Fixture offset page was a Z value and the parts ran quite well, indexing the B and C axis'.}

_{Yeah, you don't want to be comping for large errors when using RDTFO or WSEC. From the looks of it, you are doing positioning work. RTDFO will work fine for this. Just keep your parts "relatively" close to actual programmed position and you should be fine.}

 

_HTH