silly question

[batraul]

Hello all,

 

this is a silly question but i'm not sure so...

 

in the cam parameters, the chordal deviation and the filter tolerances are plus minus the value i put?

 

For example, if i write chordal deviation 0.01, is it +0.01 -0.01 or +0.005 -0.005? Is it the same for the filter?

 

thanks in advance.

[heeler]

I don't think that this is a silly question at all, I would like to know the answer as well.

[Wallace]

Hi Batraul,

 

No and Yes...

 

Filter -> removes collinear points from a toolpath that lie within a specified erro tolerance...

 

Not exist minus erro tolerance...

[batraul]

Hello Wallace,

 

As I understand, filter doesn't have minus value? And the cut tolerance, does it have minus value? For me this is not very clear in MC.

 

What should happen if my geometry tolerances are not +0.01 -0.01 and are for instance 0 -0.02, do I have to set this into the geometry? I could see in UG an intol outol.

 

thanks Wallace.

[Fig sign]

Batraul.

I think that the geometry tolerance is also + -.

If the size is 20-0.2 I always prefere to buid

it 19.9 .

[batraul]

Hello again,

 

Ok, now I now how to make when my part tolerances are not symetrical (+-). But nobody have explained me exactly what happens with cut and filter tolerances. Which one of this cannot be minus?

 

Thanks.

[camguy]

cut tolerance is the only thing you should be concerned with. the toolpath generated depends on the shape of the geometry. if you are cutting a radius on the outside of the arc, and your cut tolerance is set to .01", then the cutter will gouge the surface by .005" in some areas. if you are on the inside of the arc, it will leave .005" heavy in some areas. to test this, create 2 arcs in an "s" shape, create vertical surfaces, and run a surface finish tool path. offset the arcs by the radius of the cutter. backplot the toolpath and save as geometry. reset the tolerance, regen, and backplot again using a different color. zoom in on the toolpath and you will see the difference. hope this clears things up for you.

 

[ 05-02-2002, 08:59 AM: Message edited by: camguy ]

[gary dunn]

imagine cutting a circle. what is actually happening is that it is cutting a bunch of small lines. the tolerance determines how short those little lines are.

[batraul]

yes gary I know this one but what i don't know is:

 

If I put a value in the cut tolerance parameter what should happen? For example, if the cut tolerance is 0.001", the toolpath will be generated with 0.001" on each side of the original toolpath or will be 0.0005" on each side?