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3.5" NPT G76 Cycle

Its not having a bad attitude. I am an underling Machinist that works 2 jobs, works weekends, I literally dont have time to read an entire book. Its not that im ungrateful. Some people have one job and nothing else to do. Thats fine. So as I said Im just trying to figure out what values need to go where and that im not gonna crash. Sorry if it seems like im being ungrateful. Farthest from the truth.
 
Some people have one job and nothing else to do.
If a person is sincere about his job, he may not find time for another job. And, there is a family also, as well as friends and other hobbies.

You are sailing in two boats. Can be dangerous. Better to concentrate on what you are good at.

As regards G76, Bill has already explained it in sufficient detail. If you search the forum for G76, you will get more information. If you do not have time to read, subcontract the programming part.
 
If a person is sincere about his job, he may not find time for another job. And, there is a family also, as well as friends and other hobbies.

You are sailing in two boats. Can be dangerous. Better to concentrate on what you are good at.

As regards G76, Bill has already explained it in sufficient detail. If you search the forum for G76, you will get more information. If you do not have time to read, subcontract the programming part.
Bahahahahahaahahahahaha....Subcontract. Thats funny. Ok. read this stuff tomorrow when ready to start these nipples. There is a reason were not purchasing them as our local supplier has told us 3.5" NPT nipples/pre threaded pipes are $200 minimum and 10 week lead time. Subcontract. LOL. I am a damn fine machinist and been doing this for years. Programming is not something ive done recently but back in the day I could program 5 axis and swiss turns. But when you dont do something in 10 years you forget quite a bit.
 
Bahahahahahaahahahahaha....Subcontract. Thats funny. Ok. read this stuff tomorrow when ready to start these nipples. There is a reason were not purchasing them as our local supplier has told us 3.5" NPT nipples/pre threaded pipes are $200 minimum and 10 week lead time. Subcontract. LOL. I am a damn fine machinist and been doing this for years. Programming is not something ive done recently but back in the day I could program 5 axis and swiss turns. But when you dont do something in 10 years you forget quite a bit.
Bro you do what you gotta do. I had the same problem a few months back and this group helped me out a ton. Yes some are very direct and to the point. Youll get it done. And I completely agree with you about not remembering how to do some things on the control. It can take a few days to get back into the groove.
 
So this is what I came up with with guidance and all the resources ive found.. Think this is going to work. I am going to try it in a few minutes here.

X5. Z1.
G01 X3.8216 Z.2 F.05 M08
G76 P040055 Q0100 R0005
G76 X3.8572 Z-1.0039 P1000 Q0030 R-.0438 F.125
G00 Z.5
M09
G00 X10. Z10.
T0200
M30
 
Negative is correct.
But, R = L/32 where L is the total Z travel, including the initial axial clearance (i.e., L = thread length + axial clearance).
 
Changed


G01 X3.7286 Z.2 F.05 M08
G76 P040055 Q0100 R0005
G76 X3.8036 Z-1.0039 P1000 Q0030 R-.0376 F.125
Your X Values are still incorrect. For a Male Thread, the X coordinate from where the Threading Cycle is executed, must be greater than the Major Diameter of the Thread at the large end of the Tapered Thread. The Major Diameter is calculated by the following algorithm:
MD = X + P x 2
Where:
MD = Major Diameter
X = Minor Diameter specified in the 2nd G76 Block
P = Thread Height specified in the 2nd G76 Block

Within practical reason, the X Coordinate from where the G76 Cycle is launched can be as large as you like, right up to the X Reference Return Position of the machine. In practical terms, one wouldn't do that, but the Threading Cycle would work, albeit with a lot of Fresh Air movement in X between each Threading Pass.

Your Q values are also still incorrect. The Q value in the 1st G76 Block specifies the minimum DOC, while the Q value in the 2nd G76 Block specifies the First Pass DOC. With your arrangement of the Q values, all of the Thread Passes, except for finishing passes, will be made at 0.01"

Rule of Thumb, the First Pass DOC should be as much as the Threading Insert and the Workpiece setup can constantly tolerate. Typically, my initial First Pass DOC is 0.02" (0.5mm) then adjust from there.



Regards,
Bill
 
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