Thanks for this! It really helps to have a plan for establishing positions working backwards from the end point. And knowing to do a helical interpolation to engage and disengage the cut.
Wouldn't using a different helical infeed radius at the same pitch mean that the initial engagement with the part will be at a very slightly incorrect pitch angle? I guess it wouldn't matter, unless the pitch angle difference is enough to mean you are cutting some material that wouldn't otherwise be removed? Would it be a slightly more rigorous treatment to make the helical infeed Z rate match the helix angle of the finished part? Imagine a half-inch diameter threadmill making a 10 inch diameter 11 tpi outside thread. The pitch angle of a half-inch radius infeed is 1.66 degrees, but the 10 inch thread on the part has an angle of 0.166 degrees, so the infeed will (perhaps) gouge the part. Would adjusting the pitch of the infeed radius to a much smaller value like 110 tpi compensate for that? In the case of a 0.5 radius infeed and 2 inch nominal thread at 11 tpi, the finished thread pitch angle is 0.829 degrees, s0 the infeed pitch needs to be 22 tpi to match the pitch angle. OK, so all of this is highly theoretical, because that difference is way below tolerance limits, and how many students would ever end up programming this by hand? I guess if they eventually become teachers! Perhaps matching the pitch angles is a step too far for this lesson, but knowing HOW the paths work is probably going to make the students into better engineers, who understand how things work rather than just clicking a mill path in CAM.
Thank you sir for your video, very clear explanation. One thing i want to ask regarding the program sir, how did you compute the I & J in the G2 or G3 in the program and how did it use?
Uhh does anyone actually do this by hand? The only hand coding I do is minor fixture mods in mdi or working on a post. I feel this is the disconnect between what businesses want and what trade schools do. I could honestly care less if a potential employee can hand code threadmilling. It's more important that he know applied feeds and speeds, and how to do it in some cam software. Hand coding is way too easy to make a typo and way to slow compared to just writing it in cam or reposting a small change.
Salvadore, if employees can’t simply type up g-code even if it’s thread milling without paying attention for a typo then the are not machinists they are button monkeys, a Walmart greater can draw up shit on mastercam. NWTC is training skilled machinists not mindless machine operators. At my shop I don’t hire anyone that cannot write g-code on control. Might I suggest that you enter NWTC’s machining program to further the skills that you do not possess.
@@austinthome317 congratulations on overpaying for machine operators. are you going to tell me that your fresh out of school machinist that can write code by hand is going to be trusted to do much more than change parts? the guys with the volume of knowledge required to run one off parts or fixes to tooling have gained enough gcode experience to make the changes they need to or write it out from scratch. and speaking of hiring, can you even find operators, let alone skilled machinists in the industry these days? if you care that much they can hand write a helical toolpath by hand i'd be surprised if you didnt make them do their math with trig tables and a slide rule. i do not need to further my skillset, im well compensated and have a great position. i prefer to do things in cam because i know there are few people that can model as fast as i can, as well as having my own posts sorted for the machines i run. i've made it a priority when a post doesnt do what i want that i fix the post, and not just a hard code fix, an actual dynamic fix.
@@salvadorebertolone you do have a point when I comes with using mastercam and posts for certain machines, but that works for bigger machine shops with fancy machines what about the smaller shops that don’t have such luxuries. If you’re so skilled start your own shop and become an entrepreneur instead of working to acquire somebody else’s dream. And if you write the G-code for a helical milling cycle it’s about 10 lines of code or less and it’s a template for future use, compared to doing it on mastercam which will give you a hundred lines of code which wouldn’t be the best for older and smaller machines
@@austinthome317 its coming. the bread winner is that i have some novel tooling designed to expedite a remanufacturing process, patent will be happening closer to starting to keep it a trade secret until im open. i have some customers for this process, i have capital, just not enough to operate while starting, just getting all the ducks sorted and lined up before i order a machine... a 5 axis twin pallet horizontal, so theres a lead time on that as well. im not sure what your mastercam post is doing, but the fusion haas post does a 1" deep 1/2-13 in about 30 lines. perfect example from today, there is 1 other guy capable of programming, and setting up machines in my shop, probably close to a decade in cnc based tool and die work, wont lie, hes definitely stronger with gcode than me, but i can run circles around him in the cam. we wound up doing nearly identical jobs today, super simple, had to face off a large bearing mounting flange on a weldment. his was a 12" circular pad, mine was a 16". he had about an hour headstart on me, both machines required tearing down prior setups. i nearly caught up to him, about 5 min behind after my final pass, but my weldment had about 1/8 parallelism error in it i had to shim out which slowed me down. he had jammed his cycle, i did mine in cam. it literally took less than 5 min from start to finish. a big speed advantage i have with cam, is i often have reasonably powerful laptop next to the control and can serial the data straight from my computer to the control, no mucking about trying to hop skip jump a program to the control with usb sticks. this discorse has been useful, though, i may starting building a table based gcode generator for certain tasks, but again, this is way beyond what nearly all machine shops are looking for for future employees, bottom line is i can do what most shop leads want. they toss me a drawing and say make it. they dont care how i get from a to b. just as long as i get there, and i can get there faster than others, often with extraordinary tool life to boot because i adaptive/dynamic nearly everything. disclaimer i've exclusively been a mill guy on cncs, turning is a whole different world in this conversation.
Wow!! This is the best explained video I have ever seen!! All your videos are excellent! You are an excellent teacher!
Better than my TAFE teacher. Very well explained.
Thanks for this! It really helps to have a plan for establishing positions working backwards from the end point. And knowing to do a helical interpolation to engage and disengage the cut.
You’re a great Teacher ! Thank so much for all your videos.
Excellent instructing clear and concise
Wouldn't using a different helical infeed radius at the same pitch mean that the initial engagement with the part will be at a very slightly incorrect pitch angle? I guess it wouldn't matter, unless the pitch angle difference is enough to mean you are cutting some material that wouldn't otherwise be removed? Would it be a slightly more rigorous treatment to make the helical infeed Z rate match the helix angle of the finished part? Imagine a half-inch diameter threadmill making a 10 inch diameter 11 tpi outside thread. The pitch angle of a half-inch radius infeed is 1.66 degrees, but the 10 inch thread on the part has an angle of 0.166 degrees, so the infeed will (perhaps) gouge the part. Would adjusting the pitch of the infeed radius to a much smaller value like 110 tpi compensate for that? In the case of a 0.5 radius infeed and 2 inch nominal thread at 11 tpi, the finished thread pitch angle is 0.829 degrees, s0 the infeed pitch needs to be 22 tpi to match the pitch angle. OK, so all of this is highly theoretical, because that difference is way below tolerance limits, and how many students would ever end up programming this by hand? I guess if they eventually become teachers! Perhaps matching the pitch angles is a step too far for this lesson, but knowing HOW the paths work is probably going to make the students into better engineers, who understand how things work rather than just clicking a mill path in CAM.
Excellent!
Good video :)
Thank you sir for your video, very clear explanation. One thing i want to ask regarding the program sir, how did you compute the I & J in the G2 or G3 in the program and how did it use?
Thank You!
Start by going g0 z-30.
Uhh does anyone actually do this by hand? The only hand coding I do is minor fixture mods in mdi or working on a post. I feel this is the disconnect between what businesses want and what trade schools do. I could honestly care less if a potential employee can hand code threadmilling. It's more important that he know applied feeds and speeds, and how to do it in some cam software. Hand coding is way too easy to make a typo and way to slow compared to just writing it in cam or reposting a small change.
Salvadore, if employees can’t simply type up g-code even if it’s thread milling without paying attention for a typo then the are not machinists they are button monkeys, a Walmart greater can draw up shit on mastercam. NWTC is training skilled machinists not mindless machine operators. At my shop I don’t hire anyone that cannot write g-code on control. Might I suggest that you enter NWTC’s machining program to further the skills that you do not possess.
@@austinthome317 congratulations on overpaying for machine operators. are you going to tell me that your fresh out of school machinist that can write code by hand is going to be trusted to do much more than change parts? the guys with the volume of knowledge required to run one off parts or fixes to tooling have gained enough gcode experience to make the changes they need to or write it out from scratch. and speaking of hiring, can you even find operators, let alone skilled machinists in the industry these days? if you care that much they can hand write a helical toolpath by hand i'd be surprised if you didnt make them do their math with trig tables and a slide rule. i do not need to further my skillset, im well compensated and have a great position. i prefer to do things in cam because i know there are few people that can model as fast as i can, as well as having my own posts sorted for the machines i run. i've made it a priority when a post doesnt do what i want that i fix the post, and not just a hard code fix, an actual dynamic fix.
@@salvadorebertolone you do have a point when I comes with using mastercam and posts for certain machines, but that works for bigger machine shops with fancy machines what about the smaller shops that don’t have such luxuries. If you’re so skilled start your own shop and become an entrepreneur instead of working to acquire somebody else’s dream. And if you write the G-code for a helical milling cycle it’s about 10 lines of code or less and it’s a template for future use, compared to doing it on mastercam which will give you a hundred lines of code which wouldn’t be the best for older and smaller machines
@@austinthome317 its coming. the bread winner is that i have some novel tooling designed to expedite a remanufacturing process, patent will be happening closer to starting to keep it a trade secret until im open. i have some customers for this process, i have capital, just not enough to operate while starting, just getting all the ducks sorted and lined up before i order a machine... a 5 axis twin pallet horizontal, so theres a lead time on that as well. im not sure what your mastercam post is doing, but the fusion haas post does a 1" deep 1/2-13 in about 30 lines. perfect example from today, there is 1 other guy capable of programming, and setting up machines in my shop, probably close to a decade in cnc based tool and die work, wont lie, hes definitely stronger with gcode than me, but i can run circles around him in the cam. we wound up doing nearly identical jobs today, super simple, had to face off a large bearing mounting flange on a weldment. his was a 12" circular pad, mine was a 16". he had about an hour headstart on me, both machines required tearing down prior setups. i nearly caught up to him, about 5 min behind after my final pass, but my weldment had about 1/8 parallelism error in it i had to shim out which slowed me down. he had jammed his cycle, i did mine in cam. it literally took less than 5 min from start to finish. a big speed advantage i have with cam, is i often have reasonably powerful laptop next to the control and can serial the data straight from my computer to the control, no mucking about trying to hop skip jump a program to the control with usb sticks. this discorse has been useful, though, i may starting building a table based gcode generator for certain tasks, but again, this is way beyond what nearly all machine shops are looking for for future employees, bottom line is i can do what most shop leads want. they toss me a drawing and say make it. they dont care how i get from a to b. just as long as i get there, and i can get there faster than others, often with extraordinary tool life to boot because i adaptive/dynamic nearly everything. disclaimer i've exclusively been a mill guy on cncs, turning is a whole different world in this conversation.