hello mr Wizard :) good to see you :)
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Pretty much all of the Okumas now have high G servos so they can usually hit full rapid within about 12mm as a rule of thumb. That is usually only 1 rev of the ballscrew in most cases
that's definetly mr Wizards experience :)
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I believe that the deceleration occurs quicker than the accel since it is being dynamically braked by the motor. I've heard 3 times faster but have not confirmed other than by actual trials where thread decel needed to be short and a good thread was still produced inside of the accel value that was calculated.
yup, the hiG diagram is not symetric, and i really don't like when i have shocks durings turning, but in the end it delivers a good thread with low front/back clearances :)
like how the "k = cnc constant" varies with machine type, also "acceleration" times varies with machine type : somehow is the same thing, a heavy turret will be slower than a light one, but still, the numbers are good, and i guess that anyone who delivered a thread with low clearances has saw that :)
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With a little creative thinking, you can calculate the needed value from your formula. I typically use 2mm clearance unless working with castings
i use 5 and dynamic indexing :) after finding this chart, i will calculate those distances for my specs, and maybe i will also reduce this clearance :)
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On another note, the Load monitor immune time is set to .4 second which is plenty in nearly all cases. You may need to shorten it in order to monitor such things as peck drilling or threading since the feed motion may not be longer than .4 second in some cases
now i don't monitor threads, since the operator is near the lathe :)
and drilling with circa 0.4 + LM is not common :)
... if tool is little, it can not be sensed
... if tool is big, and cutting is for 0.4 seconds, than is a rare situation
... if tool is normal, than is the case when you try to cut deeper, chips dont go out, etc ...
about particular cases, i would like to tell you that i monitor cutting inserts ( generally width=3 ) with caution :)
the cnc can not feel this insert, but it can feel if the insert is broken and the holder is making contact with the part :)
thus a good limit may save your holder when the operator is not paying atention : well, is a bit hard to react, especially if material has a tough crust :)
so far i saved the holder many times :) .... and i trashed many holders before :)
so during a setup i always have a warning on the cnc scrren, because of the limits :) but it works :)
all the best :)