[marshal_]

Hello. LB3000 EX II machine with OPS300LA. When tapping, with cycle G71, it does not perform a chamfer at the exit according to M23. What parameter is responsible for this?

[Algirdas]

what I would do at the first place:
remove M23 from the line
check animation again.
Check the right top corner where yellow toolpath lines ends and orange lines go straight up making something really similar to chamfer.

next step:
start point of the shape and exit the shape. Make the start point higher on Z axis and the same with retract point.

[deadlykitten]

hy marshal why do you need to control the end chamfer ?

next infos are from the manual :

L : Chamfering distance in final thread cutting cycle. Effective when M23. However, if L is not designated when M23 is effective, L will be the amount of 1 lead when starting thread cutting.

The feed rate used for chamfering in the X-axis direction is set at Feed rate of chamfering in thread cycle of optional parameter (OTHER FUNCTION 1).

Therefore, the chamfering angle is determined by the feed in the Z-axis direction (designated in the thread cutting program) and the feed in the X-axis direction.

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in conclusion, for g71 & g33, the end chamfer can not be programed only from g-code, because it also requires a parameter set; in other words, you need to run trials on the machine, in order to discover the proper parameter value, and, if you will change programs specs, then you will need to adjust the parameter again this is time consuming

if you only wish to do this for fun, or to achieve a more aesthetic thread, then fill free to run trials and gather your own conclusions; you may reach a situation where z motion stopped, but x slowly ascends, and, after a while, x will rapid up, thus you will feel that you can't control this behaviour; however, even without messing with the parameter, most threads look ok

if you need to deliver a vansished thread, then precise control is needed, and this can be achieved with g34; in other words, with g34, what you are programing is exactly what you will get / kindly

[deadlykitten]

one more thing : pls check attached image : your specs are too high to obtain the normal end chamfer, because deceleration is too agressive in other words, the end chamfer may look better if you decrease your rpm, but it may be hard to notice such difference / depends

What parameter is responsible for this ?

i also attached para location for X feed when chamfering

ps : is that an 0.1um control ?

[Algirdas]

Make the start point higher on Z axis and the same with retract point

My mistake. Higher is X axis

[deadlykitten]

i just had an idea, in order to shorten your trials time :
... set L at higher value: it's max value should be 11+z_clearance; i would start with L8
... set that paramater at 3000rpm*1.5feed=4500, or 4500/2 or 4500*2; thus maybe you should use half, or double, considering that x axis is on dia, and having no clue how does the x axis raise up during thread chamfering ?! i could find out, but is not a must for now

theoretically, a bigger L should produce a larger vanish cone, and, if that is too large, then you can shorten it by decreasing L, or messing with the parameter

so : use a big L, and, if end chamfer is too big, then decrease L and restart; thus, within a few restarts, you should get results / kindly

ps : like algirdas said, if i got it ritght, go also for a bigger X clearance, in order to have enough room for the x chamfer motion to execute

[marshal_]

Thanks for answers. But in trial ONE touch IGF, the same program gives a completely different picture. There are most likely other parameters, but what are they?