threadmill allowance

[Thoob]

Hi Guys, when you program threadmills, how do you typically approach it? I always draw a circle of my tap drill size and threadmill the entity. For example if I'm cutting a 1/2-13 thread, I'll draw a .422 hole and program the entity. Now in my allowance, I would typically put .04. Is this normal or do you guys use a different method? I find I always have to adjust my wear to make the thread on size. The thing is, its always a different amount for each thread size.

[Metalmuncher]

I pick a point and put in the major diameter, usually very close.

[Guest]

I always draw the major for OD and Minor for ID and cut it that way

[Thoob]

I pick a point and put in the major diameter, usually very close.

Where in the parameters do you enter the Major Diameter?

 

I always draw the major for OD and Minor for ID and cut it that way

 

So do you select entity/point or automatic? Do you use the minor or the major? Seems almost like how I do it. I always use minor as mentioned in my original post. Its weird mine never get close enough.

[Mr. Wizzard]

Here's how I do it.

Point only, always.

[Thoob]

Thats weird, my option to select Major Diameter is grayed out. i can't select it. Am I missing a parameter somewhere?

[Mr. Wizzard]

That's why I always use point. If you select the arc, it will usually "inherit" the major diameter of the arc. If you select a point and it shares the center point of the arc, it will "inherit" the major diameter of the arc associated with it. You can cheat it if you create a point slightly above the arc (Z .500 above), then select that point. It won't be associated with the arc, then.

[Thoob]

Ahh. Ok, I get it now. Thanks for the info. I will try points and see how they come out. Appreciate it.

[Mr. Wizzard]

no problem. Do a search for thread milling. There's been some recent ones with pretty good info on tackling them. If you take your time, it will work out awesomely!