step over controll

[sml2011]

Hi to all

 

 

Can some one tell me :

 

Does the step over control (Distance - scallop high) effect on final result (quality of surface finish)?

 

 

witch one is better ?

 

 

 

Thank you

[kh012]

For roughing i use the stepover. For finishing i use the scallop to control the max. cusp size on the surface. the smaller cusp means less manual finishing of the surface.

Ken,

[chip]

For roughing i use the stepover. For finishing i use the scallop to control the max. cusp size on the surface. the smaller cusp means less manual finishing of the surface.

Ken,

 

+1 I think, (if you search scallop height in help), step over is amount (or percentage) the tool is in material, 'scallop height' is the amount of material leftover by the tool after the toolpath.

 

I talked with the 'surfcam boys' and something they've been working on is step ever in pocket(s) roughing.... he was claiming it was cool. I didn't see it though. Ive never really seen surfcam either.

[Colin Gilchrist]

sml,

 

Both settings (Distance or Scallop) will give you the same result. Scallop Height is a setting that lets Mastercam calculate the stepover distance, based on the desired scallop (cusp) height, and tool size. 'Distance' lets you (the programmer) set a physical distance that you want the tool to step over.

 

The difference between the two is really just your personal preference. Do you want Mastercam to calculate the stepover automatically, based on the approximate cusp height, or do you want to set a physical step over amount yourself?

 

You can find online calculators that will help you equate Scallop Height with Surface Finish values.

 

You will need to cut some parts with different step over values (or look in Verify with tight tolerance settings) to get an idea of what kind of surface finish your tool will leave.

 

The same step over value will leave different cusp heights with bigger or smaller tools. Take a step over of .025 inch. If you are using a .125 Ball endmill, this would leave a fairly rough surface finish. If you used the same .025 step over value, with a 1" Diameter Ball endmill, the surface finish would be much smoother, due to the increased radius of the tool.

 

Hope that helps,

[Festus]

unless it's a critical part I always use stepover. Scallop on an outside radius can take forever and for me the faster I can get the part off the machine the more money I make!!

[LaszloK]

I prefer scallop since you can use the same values reguardless of cutter size and MC will do the math. You need different stepover values when using different size cutters to achieve the same surface finish.