ball mill path..

"Tom L" wrote in news:- snipped-for-privacy@dls.net:

I don't know if this is the easiest way or not, but this is the first thing that comes to mind.

Make an offset plane .15" above your surface (R.25-.10 depth = .15). Make a sketch here with a centerline, two 90° tangent arcs, and a line to close them.

___________ (___________)

Use Cut-Revolve 360° to make your first cut.

Start a new sketch on the same plane and due the same thing, perpindicular to the first. Use midpoint contraints to the first sketch if that is desired behavior.

MHill

Depends on what you mean by "do". If it's a flat surface, G-codes are almost as easy as modeling the cut. Insert, Cut, Sweep a flat bottomed, U-shaped path piercing the center of a 1/4" dia profile. If the surface isn't flat, you'll just have to draw the path to match an offset of the surface. G-codes for that will be a bit more involved.

Create a sketch of the cross. (.500 wide 'arms') extrude .100" into the body, 1" out of the body uncheck 'merge result' --> ok add .25" radius to edges/faces of cross combine --> subract

This will leave you with a .100" deep pocket that will be created by a .500" diameter ball end mill.

HTH

Thanks for the help, I have learned a couple things.. However, I'm still having the problem..

For clearity, saay I want to machine a simple K in some plastic, and do it with 3 machined lines, using a .25r ball mill, going .100" into the service. For CNC stuff, that's basically 3 G01 statements to cut the lines, and plenty easy.

So, the question is, how do I do this operation in solidworks? If I have a simple circle or something, I can cut-sweep all day, but when I get a sharp bend or intersecting curve, it bombs out.

cschultz way was pretty cool, but if I wanted to ball mill "SOLIDWORKS RULES" I would be there for a long long time.

I imagine having a sphere, a solid object, and then sweeping that along the path, and subtract what it hits?

now why would you want to engrave that in anything?! Just kidding, I really like SW. It's usually the drivers of the system that have issues......

I taught myself that method after banging my head against my desk trying to get a pocket created with a BEM to look right. The sweep thing wigs out if it doubles back on itself. You will probably have to do each leg of the 'k' as separate bodies, fillet, subtract....if you want it to look right.

just model it as a slot, set the CNC code up like you were cutting a slot, and then swap the tool for a BEM and call it a day, Don't spend all day getting the model to look like what you want, spend part of the day making the model that will yeild you the part you want. Or just place a sketch on the top, and on the machine minus the depth value to the z tooloffset(if in a normal 3 axis mill).

If you're engraving with a ball end mill and it's just cosmetic I wouldn't bother to create 3D geometry for it. I used Pro/E before solidworks and when we had to engrave we'd generate cosmetic sketches using single line text (essentially the path of the ball end mill). A note on the drawing would call out the desired depth and width of the lettering.

Then in Pro/NC the programmer would choose to run an engraving sequence using the sketched text and choose a ball end mill as his tool.

This has the benefit of keeping the part simple, being fast, and providing lines and arcs for the tool path.

So I'd suggest just sketching your text on your surface and programming to that.

shaun and - thanks for the great tip.. I guess my thinking has been "accuracy in, accuracy out" - but I guess I need to think a little more on my own :-)

Thanks!

I was actually trying to create a macro for this basically the output would be a sweep that can have intersecting geometry or a "solid sweep" anyway I got it to work with a tool path that was in the ZX plane but abandoned it because my wife was complaining that I didn't have a promise to pay. I would finish it if I had a PO. If you use it much e-mail me @ corey scheich at this doesn't belong hotmail dot com