thread milling

[elraiis]

hi all

if its no much trouble i was wondering if someone could help me out with thread milling. i have a part to make in inches but there is a metric tap in it. M42 .75pitch and i need to do it using thread milling. never used that function before and the fact its metric is not making it any sweeter either cause last time i touched metric was few years back its all lost. I opened up the thread milling function.. looks pretty simply except for the fact i don't have the thread mill tool in the library of mastercam. But i don't assume that would be a problem i'll just put a 1" Flat Endmill or so. so now in the thread mill window what do i do? ok my tool is a 1 insert so that ok. and my thread depth is -1.4. now on thread pitch i simply convert .75mm to inches and i put that there? meaning 0.0295? is that correct? and my last and most important question is the feed and rpm?!!?!? is there a method to calculate that? is it the same way i do for using a tap? i would doubt that.. am not sure and so am asking. sorry guys but never did i use this feature before and i dont wanna make an earthquake at work caused by a dumb mistake. thanks.

[Guest]

elraiis,

 

There are a couple of threads right on the front page about others that a threadmilling for the forst time. Might want to check them out.

[DavidB]

John,

 

Forst orient

[Jaz]

Figure feeds and speed just like you would an end mill. Keep in mind that for an internal thread the cutting edge will feed much faster than the center of the tool. Your pitch calculation appears to be correct.

[Jack Neelands™]

"forst and firmost"...run the tool well oversize so that you can check the pitch and get a good visual of what you are cutting

[elraiis]

thx guys

[GeoGirl]

Got another question for ya guys,

 

how come when you post a thread mill, its all linear moves, not using arcs?? Is this normal?

I haven't tried to thread mill yet. Have some to try... soon :-)

 

Thanks again, eh

GeoGirl

[DavidB]

Turn filter on, create arcs.

[Guest]

There is a switch on the thread mill parameters page that says linerize helixes, uncheck that.

[Martin Oline]

GeoGirl:

I have a Hurco VMX42 and it always posts linear moves for thread milling. You can select the Linearize Helixes and set for fine graduations but it posts lines regardless

 

MartyMan

[GeoGirl]

the linerize helixes is already unchecked. Where do I find the "Turn filter on, create arcs"

 

Thanks again

GeoGirl

[Guest]

Geogirl

 

What version of MC are you running and what post processsor.

 

I am thinking your post is not set up for helical arcing.

 

If the linearize didn't work that probably means your post isn't outputting them.

 

 

BTW, the threadmilling toolpath does not offer filtering.

[Guest]

Check your control def if your using X

 

Control Def >> arc >> make sure you are set for helix support.

 

If your using V9 check your post for this

 

code:

---

helix_arc   : 1     #Support helix arc output, 0=no, 1=all planes, 2=XY plane only

---

Make sure it is not set to 0

[GeoGirl]

Hi John, I am using 9.1 and the MPFAN, we have a fanuc 18oimb controller. I will check my post processor - yes your right, it was set at 0 and now I changed it to 1, thats fabulous.

 

Thanks a bunch.

 

GeoGirl