Ball End Mill Sweep

[ndogg1080]

Is there a way to do a clean sweep that imitates the shape a ball end mill? I'm trying to create a path that has 90 degree bends and whose end product looks like it was cut by a ball end mill. If there's a way to avoid sweeping the straight areas and then revolving the corners, I'd be happy to know.

Thanks!

[JDMather]

>Thats not a 90 deg (right angle) tool path...Thats a tool path with a radius at the corners...

And how small of a radius can you measure. For all practical purposes the radius in my path is zero.

Certified Journeyman Machinist - 8 years on the shop floor.

[Anonymous]

> 2008

Thank you. I'll have to look up a 'what's new'.

[HallStevenson]

Is it "correct" though ?

[Anonymous]

> and thats exactly how Inventor treats a right angle sweep path too.

Wrong. IV mitres the corners like Pro/E does.

[mcgyvr]

"Certified Journeyman Machinist - 8 years on the shop floor"

(Good for you but your Inventor file is incorrect)



JD, your model is incorrect, my file is correct. That's it. Go try for yourself.

Insert ball end mill into Bridgeport collet,secure material in vise, turn Z axis handle to lower tool into material, turn X axis crank to move in 1 direction for 1 inch, turn Y axis crank to move in perpendicular direction, stop, remove part from vice. Look at part and see the "Y" corner marks exactly like in my file not a "V" like you guys have.



Sorry guys inventor you cannot reproduce the proper cutout from a ball endmill with a single sweep. That's it.

[Anonymous]

> Is it "correct" though ?

It isn't correct for the application but is pretty much standard
for a sweep function when it's given a G0 trajectory. The assumption
is for a mitre rather than revolving about the 'point'.

[JDMather]

>Insert ball end mill into Bridgeport ...

The path I cut can't be done manually - it is not a simple x then y move. If you go back and read the OP original post I interpreted what I think he really meant as perhaps he doesn't have the experience to properly state the problem description. In my first response I indicated it was my interpretation of the true problem description with the phrase, "Something like this?" Then you said my geometry in Inventor and in SolidWorks is incorrect. It is not the geometry that would be created by the straight line paths you describe on the Bridgeport. It is correct geometry for the paths that I used, not for the path you used. I did not use the same paths as you. I think we are talking about two different problem descriptions.

[mcgyvr]

See attached, This is exactly what I interpreted the OP request as and this is how it will look when done in the real world.

[Anonymous]

> I interpreted the OP request as and this is how it
> will look when done in the real world.

If it's identical to your neutral it's understood.
Now it's up to the OP to clarify intent and there should be
enough info to cover all the bases.

Let's move on to something interesting.
Anyone wanna do barrel cams? ;^)

[JDMather]

>...what I interpreted the OP request

I already knew exactly how you interpreted the OP problem statement and never said your geometry was incorrect. (although in this latest attachment it is incorrect as you can't end a ball endmill slot like that).

[mcgyvr]

JD that latest attachment from me IS correct. I'm holding the part in my hand (just made on a HAAS CNC machine) as we speak and it is IDENTICAL to my file.

Why can I not end a ball end mill slot like that? I just did on the cnc machine. .250 dia ball end mill, Touched off tools to top of material, jogged Z axis down -.125" , jogged Y axis +1", jog +1" in X axis and then jogged Z back up +.125". Resulting part is IDENTICAL to the latest model from me.

[JDMather]

LOL, my mistake - when I pulled the end of part marker down I missed the last revolve cut feature.

[Anonymous]

I believe the shape of the cut will be different depending on the machine and method, a manual machine running a true square toolpath will give a result like mcgyvr says is correct. Your example can be generated on a CNC machine by programming using cutter comp with the tool radius as the offset. If a true square toolpath is programmed, then the result will be just like the bridgeport.



My point is that the shape the ball end mill leaves is the material is dependent on the machine used and the method of toolpath generation.



Inventor cannot reproduce the straight line toolpath with a single sweep, correct.

JD's example using a single sweep can be produced on a CNC machine, it is correct also.

[mcgyvr]

All good!!

I thought that might have happened. Still interesting how solidworks and its solid feature sweep didn't produce the correct geometry also in the corners.

[JDMather]

>Still interesting how solidworks and its solid feature sweep didn't produce the correct geometry also in the corners.

How so?

[mcgyvr]

It's back to the should be a "Y" in the corners and not a "V"

The image you post from SW is not what a ball end mill in that path will look like. Maybe it's just how SW represents it graphically.

[mcgyvr]

See attached image showing the "Y" (correct) versus the "V" (incorrect)

[JDMather]

>in that path will

Which path are we talking about? The same thing can be appoximated in Inventor with a curve driven pattern of the cutter location.

[Anonymous]

> Maybe it's just how SW represents it graphically.

I certainly hope not.
Render meshes are created from the b-rep geometry descriptions.
What you see should be what you got.

The pictured geometry is perfectly appropriate for a tangent
chain sweep path. ("bend"?)

You are stuck on a G0 sweep path. ("jog"?)

[Anonymous]

style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">

"hallstevenson" wrote in message
href="news:6077091@discussion.autodesk.com">news:6077091@discussion.autodesk.com...

Is it "correct" though ?

No the only way that cut could be made as shown
is by an EDM sinker. There are no radii shown on the outside corner as there
would be had an ball-end mill cut it.

Rich