3d chamfer with a ball em

[Santa Fe]

Have anybody used Contour 3D-chamfer toolpath with a ball em. I would like to use this toolpath to deburr 3D-edges of parts, but the result is inconsistent. At straight 2D edges it works fine but at 3D-contours it makes deeper cuts than what I need.

 

Have anybody had good results when using this toolpath to break the edges of 3D contours.

[Matthew Hajicek - Singularity]

One of my pet peeves. If you want to do that you have to generate the path yourself in wireframe, which I end up doing quite frequently.

[tedly]

use surface finish shallow.

[Bruce Caulley]

Or put a chamfer on the model and use flowline with the ribcut box ticked.

 

Bruce

[Bryan Johnson]

I have been using Surface->Finish->Project, but after reading the suggestion from Bruce, I plan to give the Ribcut method a try.

[Santa Fe]

Tedly,I did create wire for all the 3D-edges.

 

Bruce, what size of chamfer you use and are you allowed to modify your customer original models?

 

Why to come up with patches and/or modifying the original customer models to deburr the edges of the parts.

 

How can we encurage CNC Software to review this Contour>3D chamfer with a ball em toolpath, so it will do a nice and even cut all along the edge of a 3D part. I am sure that lots of programmers will enjoy having a reliable deburring toolpath like that.

[Hardmill]

 

How can we encurage CNC Software to review this Contour>3D chamfer with a ball em toolpath, so it will do a nice and even cut all along the edge of a 3D part. I am sure that lots of programmers will enjoy having a reliable deburring toolpath like that.

 

 

A surface toolpath is the proper answer, how is the tool to know where to drive with

only a chain and a constaintly changing heights ??

The tool vector is always changing

 

Sometime changing to tool center (vs tip) will net somewhat better results. but not always

 

 

 

 

 

 

 

 

 

PEACE

[Joe788]

Santa Fe, do this and you'll be happy:

 

#1- Take that toolpath you have above, change it to 2D CONTOUR, raise the Z depth, top of stock, retract, etc, all well up above the part.

#2- Change the stock to leave on walls to negative 1/4 diameter of your cutter.

#3- Ghost that operation so it doesn't post

#4- Use Surface>Finish>Project>NCI, select the entire part as drive surfaces, and use Stock To Leave on Drive Surfaces to control the size of your chamfer. Select your ghosted toolpath as the NCI.

 

And boom goes the dynamite, perfect 3D chamfer. If you're working with a part that doesn't have any real steep walls, you can do the exact same process with a regular 90 degree chamfer tool with excellent results.

[Santa Fe]

I tried the Surface->Finish->Project with the Ribcut check marked (first I made a .010" chamfer on all edges which is much extra work) and it did not work consistently on all edges.

I have also tried Surface->Finish->Project in the past using curves and NCI with no good luck either.

 

Joe to get a close to 45² chamfer edge multiply EM diameter * .15

 

Hardmill, I agree a surface toolpath is needed so the ball em can follow the intersection edge of two surfaces and compensate for the changes in vector direction.

 

If anybody have succesfully accomplished a consistent debured edge, would you please share a sample file by loading it to the ftp.

 

Thanks to all.

[JDowe]

Offset the geometry in the z direction using offset contour

Planes will have to be set parallel to each side to get offet to work

Then offset this geometry in the xy plane

Then program a 3d contour using cutter comp to center of ball end mill

The key is that the offset is not the cutter radius but the radius where the cutter

contacts the part

It is not too difficult to get this number graphically - see the attachment for details

I can e-mail you a sample part if you wish - I am not familiar with uploading the files to the web site

[JDowe]

These calculations should allow the X Y and Z offsets for using a ball endmill to cut uniform chamfers

The easiest way to do the Z offset is to offset surfaces nad put edge curves on

Program the toolpath to the center of the ball endmill

 

It should be possible to write a script to do these calculations automatically

[JDowe]

OOPS

 

Formula for T should be T = COS A x H

[LansB]

I just dug this up in search of something a little more efficient than the project method, which is what I have always done... nothing

 

I really think Mastercam should try and incorporate some kind of toolpath specifically for this, that doesn't require so much work. In today's age, we really need to be able to fully deburr a part in the machine and do it competitively.

[Teh Bear without Brains kinda idiot]

I used 5 axes contour 5x with output format for 3x

[Roger Peterson]

For those that need to do this type of work on a regular basis I have recommended people purchase the curve and drill 5 axis toolpaths just as "Teh Bear" mentioned. It's incredibly simple to do with the curve 5 axis toolpath. Basically a contour toolpath with surface compensation.

[Matthew Hajicek - Singularity]

Roger, would you mind doing a basic walkthrough of it?

[neurosis]

Santa Fe, do this and you'll be happy:

 

#1- Take that toolpath you have above, change it to 2D CONTOUR, raise the Z depth, top of stock, retract, etc, all well up above the part.

#2- Change the stock to leave on walls to negative 1/4 diameter of your cutter.

#3- Ghost that operation so it doesn't post

#4- Use Surface>Finish>Project>NCI, select the entire part as drive surfaces, and use Stock To Leave on Drive Surfaces to control the size of your chamfer. Select your ghosted toolpath as the NCI.

 

And boom goes the dynamite, perfect 3D chamfer. If you're working with a part that doesn't have any real steep walls, you can do the exact same process with a regular 90 degree chamfer tool with excellent results.

 

 

Not to go dragging up an old post, but I used this method yesterday on a fairly complex 4 axis part and it worked amazingly.  I want to give you some kudo's Joe. This is a trick that I will be putting in the spank bank. 

 

Would be nice if our 3d champher function worked "at all".   But this is a great alternative.