Threading

More
02 Sep 2013 18:34 #38424 by BigJohnT
Threading was created by BigJohnT
This is my G76 threading subroutine. Place the attached image in the same directory.
(info: G76 Threading)
o<g76> sub
#<tool>         = #1 (= 7 Tool)
#<rpm>          = #2 (= 250 RPM)
#<diameter>     = #3 (Diameter)
#<tpi>          = #4 (TPI)
#<inital_depth> = #5 (= 0.010 Inital Depth)
#<thread_depth> = #6 (= 0.045 Thread Depth)
#<spring_pass>  = #7 (Spring Passes)
#<z_start>      = #8 (= 0.100 Z Start)
#<z_end>        = #9 (Z End)
#<x_offset>     = #10 (= 0.025 X Offset)
#<q_angle>      = #11 (= 29.5 Combine Angle)
#<taper>        = #12 (= 0 Taper 0=none 2=exit)
#<coolant>      = #13 (= 8 Coolant 8 On 9 Off)

#<pitch> = [1/#<tpi>]
#<radius> = [#<diameter> / 2]

G8 G18 G20 G40 G49 G97
T#<tool> M6 G43
M#<coolant>
S#<rpm> M3
G0 Z#<z_start> X[#<radius> + #<x_offset>]
G76 P#<pitch> Z#<z_end> I-#<x_offset> J#<inital_depth> K#<thread_depth> Q#<q_angle> L#<taper> E#<thread_depth> H#<spring_pass>
M5 M9
G53 G0 X0 Z0
o<g76> endsub

JT
Attachments:
The following user(s) said Thank You: DinukaShehan

Please Log in or Create an account to join the conversation.

More
14 Jul 2017 02:38 #95784 by 10K
Replied by 10K on topic Threading
Here's another version of a threading subroutine. I designed it so that you have to input the minimum amount of information - the nominal diameter, the TPI, and the length of thread. It's in imperial units, but could be converted fairly easily if desired.

My lathe has manually controlled speed, so that is not set by the subroutine.
Attachments:
The following user(s) said Thank You: DinukaShehan

Please Log in or Create an account to join the conversation.

More
17 Aug 2019 15:45 - 17 Aug 2019 19:34 #142393 by DinukaShehan
Replied by DinukaShehan on topic Threading
Can threading with manually controlled speed(without vfd) lathe with this command lines?
I can measure spindle rpm with handheld tachometer!

don'tyouhavemetricthreadsub
Last edit: 17 Aug 2019 19:34 by DinukaShehan.

Please Log in or Create an account to join the conversation.

More
23 Aug 2019 14:31 #142958 by 10K
Replied by 10K on topic Threading
I don't have a VFD. Speed control of my lathe is outside of LinuxCNC. I do have two detectors on my lathe spindle. One is an index that gives one pulse per revolution. The other is a proximity probe that counts gear teeth to give several pulses per revolution. If I recall correctly, you can also have a second detector on the gear teeth to give direction, but it's not absolutely necessary for threading.

The one pulse per revolution is needed, as it assures you're starting the thread at the same location each pass. This is absolutely necessary.

Multiple pulses per revolution allow you to change the rpms on the lathe during threading.

I don't think it would be possible to have only the reading from a handheld tachometer to thread.

If you need the metric version of the threading subroutine, I think that I wrote one. I'm away from my system at the moment, and can't check. Just let me know.
The following user(s) said Thank You: DinukaShehan

Please Log in or Create an account to join the conversation.

More
23 Aug 2019 20:50 #143010 by DinukaShehan
Replied by DinukaShehan on topic Threading
Yeah or jah
Thank you 10k.
Good explanation there.
Can you please add a metric sub when you could.

Please Log in or Create an account to join the conversation.

Time to create page: 0.087 seconds
Powered by Kunena Forum