Need help on toolpath decision, surface

[Jeremy Grigsby Excelsior Marking]

I have a part that is a retangular block and it has a pill shaped surface cut out of it. Imagine two spheres connected togetherwith the same radius as the spheres. a mold for a long tylenol capsule. I hope im coming through clear. Whats the best toolpath to finish this with? I'm using a ball endmill.

[Jim at Gentex]

I like Toolpaths>Surface>Finish>Parallel for most simple applications, but there are a number of ways you can go about it. A tight step increment and proper speed and feed will give you a decent surface finish.

 

HTH

[Jimmy Wakeford from Barefoot CNC]

Maybe:

surf-rough pock

then flowline or scallop

[Jeremy Grigsby Excelsior Marking]

I uploaded the file to the mc9 folder of the ftp. its called 8x6 block. It seems so simple i just dont have any surfacing experience

[Storkman]

surface-finish-project-blend-spiral-along-3d would do a nice job as well.

[Leon-ZA]

If this is a casule cut along it's length I'd start with a surface rough pocket then finish it with a surface finish contour.

 

On second thought, the product would probably look better with a surface finish parallel cut.

 

Just remeber to keep the chips out of that cavity! If your cutter starts rechewing them your finish is really gonna suck. And climb climb climb!

[Jeremy Grigsby Excelsior Marking]

im trying to use a filter on the thing cause its just arcs at different z levels but it doesnt work right, keeps putting random lines it the middle of arcs

[archer]

I agree with all the parallel finishing posts.

 

I'd use the surface finish parallel for finishing after you rough. Depending on your finish you would like to achieve, i would also run another parallel finish pass with a stock allowance of .003 before the finish.

With the finish, i would use tolerance of .0003, step over of .003, zigzag, and angle of 45.

 

Gap size set to .15, following surfaces, and check gap motion for gouge the only box checked under gap setttings.

 

Under advance settings, I would pick the only between surfaces for roll tool. These options gave me one rapid move to start, and one at finish. The tool stayed down through the entire part.

 

This may work for you???

[cblythe3d]

Climb cutting flowing from the bottom up for finishing produces great results. After all the surface speed at the bottom of a ball mill in theory is zero. By Stepping your cuts from the bottom up you cut more on the periphery without dragging.

 

You might find the speed and feed for the insert tool a little agro but that small DOC it is in line with catalog values.

 

 

The closer the cutter R is to your part R the smaller the scallop and the larger your step.

 

if you change the cutter direction as in any zig zag program the tool alternatly shears then tears the material. Really efficient machining though with no monkey motion.

 

I posted a sample that should make aluminum shine but keep the tools real short.

 

You guys are cool

Thanks Charlie

[Leon-ZA]

Jeremy. That sounds like broken surfaces. Try increasing your gap% to keep the tool down.