Haas G76 Threading problem....very puzzling.

[wrustle]

Guys, thanks to each and every one of you who commented, it was a great help!


I have seen where my mistake was made and cannot believe since July of last year this is the first time my incorrect template has caused an issue.

In the Haas programming manual the G76 "K" value is defined as "Thread height, defines thread depth, radius measure" That's exactly how it's written.

My mistake in my template (which I set up on the very first threading job) was, I was subtracting the "PITCH" diameter from the Major diameter and dividing by two when I should have been subtracting the Minor diameter from the Major diameter and dividing by two. With all the small parts we make it was never an issue.

My threading code was G76 X1.543 Z-6.43 I-.0035 K.051 F.1667 With the Major Dia. mean = 1.738 and the Minor Dia. = 1.543 my K value should have been .0975" NOT .051"

With a 6 pitch thread, that's a big ass chunk of material going from the pitch diameter to the minor diameter.

No wonder I have been threading so quickly these past several months!!

Best Regards,
Russ

 

[Ox]

Print it out and put it in your programming manual.
I did:

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Think Snow Eh!
Ox

 

[jdowd]

Forget about pitch diameter at this point. K X 2+plus x(minor thread diameter)= major thread diameter. Then play the d in as deep a cut as you can for first pass(d is only for first pass). It will cut down on extra passes. Settings 86,99 control depth per pass and finish pass depth.