thread problem

[mc_91]

hi all,

 

although not exactly a mastercam related problem any help will be appreciated.

 

need to make an inner thread with the following data: diameter of thread is 308.2 m"m.

pitch is 8 m"m.

length of thread is 158 m"m.

rpm=60,start of material is z0.

 

an absolute restriction is that start of thread at zero point must be at 7 degrees to the right of vertical (83 degrees from horizontal).

 

anybody knows some method how to calculate the toolpath for this kind of work?

 

thanks in advance.

[pip]

Have you loked at toolpath thread mill, think its under /toolpaths/next menu/circl toolpaths/threadmill

[pip]

Soory did'nt see it was a lathe subject.

[chip]

Depending on the MasterCam your running. (Metric or Standard)I COULD'NT READ YOUR PROFILE. Your question is a bit shady! I would conver the numbers to standard.

 

quote:

---

need to make an inner thread with the following data: diameter of thread is 308.2 m"m.

pitch is 8 m"m.

length of thread is 158 m"m.

rpm=60,start of material is z0.

---

308.2 mm = 12.13 in Dia

 

8. mm = .3149 in pitch

 

158 mm = 6.22 in depth

 

THREADMILL, Unless you have a tap.

[Philcott]

Gilsu,

 

quote:

---

an absolute restriction is that start of thread at zero point must be at 7 degrees to the right of vertical (83 degrees from horizontal).

---

Are you saying you need the point where the tool makes contact with the face of the part to be in a particular location so as to align up with a feature on the part? If so, I believe you will need to adjust your "Z" start position to give you the proper start. For the most part you will need to get this through trial and error. You can do some math to get you where you want to be after you cut your first part. Lets say you are off by 90 degrees, with a thread pitch of 8 m"m, you would want to change the approach "Z" location by 2m"m.

 

What does your m"m represent? micro meters?

 

Phil

 

EDIT: This seems to be a lathe question where larger threading is done using single point tooling.

 

Chip,

 

quote:

---

12.13 in Dia

---

That's one hellava tap. Wow!

[Guest CNC Apps Guy 1]

IMHO, threadmilling is the ONLY way to accomplish a specific entry/exit angle/position. If you're doing this on a lathe, then lathe needs to have rotary tooling and C-Axis.

 

JM2C

[jeff]

quote:

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I believe you will need to adjust your "Z" start position to give you the proper start.

---

+1

I have had to do this in the past when I could not put the part on a mill.

But James is correct once again,the best way to do this is on a mill.

[mc_91]

thanks everybody for the quick feedbacks.

 

to clarify myself it is a piece for lathe machining, and the lathe is a vtl standard with no rotating tools. dimensions are in metric system.

 

to PhilCott:

thanks, you understood my problem. i also thought to make it with trial and error method but wanted an alternative way to figure it out. anyway thanks again.

[Philcott]

James,

 

I thread milling can you designate where the tool will make contact or is it a bit of trial and error as well?

 

Phil

[jeff]

quote:

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I thread milling can you designate where the tool will make contact or is it a bit of trial and error as well?

---

You can start anywhere you like.

[Philcott]

Gilsu,

 

The problem is knowing where the lathe will pick up the start of the thread and you will only know that by making a part. If the other features can be put on after maybe the orientation can be set there. Also once you have made a thread, changing the RPM will alter where the machine picks up the starting place so be carefull with that as well.

 

Phil

[Philcott]

Jeff,

 

Is that done by drawing the thread breakout where you want it?

 

Phil

[chip]

quote:

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Is that done by drawing the thread breakout where you want it?

---

In mill, Absolutly you can draw the thread and cut it ....I've never tried that on our lathe (cutting a spline).

[Guest CNC Apps Guy 1]

You can't do it with repeatability unless you have C-Axis, even if you orient the spindle before starting.

 

Phil, you can start anywhere you want.

[mc_91]

thanks again PhilCott

 

making the thread is the last operation so all features are ready by then.

it's also a buttress thread so it can't be done by thread milling.

alas, thanks for all.