[RAF.]

Anybody having trouble moving the start point for Equidistant Offset, using start point modify?.

I can not get it to move to desired location. Maybe something I am doing wrong any help would be appreciated.

Thanks
RAF.

[mmoe]

I'm not sure if using a drive curve in that example is a good idea, so I have to wonder if the problem is related to the use of the drive curve. Since the concept in Equidistant Offset is kinda new, I could be completely off on this, but I see drive curves as an option when you don't have a closed loop, as in one or two curved running along the length of a selected pocket or profile. Using a drive curve when it's closed like this doesn't seem like it's going to serve much of a purpose and because of the geometry of the drive curve, may affect the start point. Try removing the drive curve option and see what happens.

[mmoe]

I made a quick similar model and tested it out. I get the same result you do, that the drive curve option for changing the start point does not affect where the toolpath starts. While I also get a very similar toolpath without the drive curve, I can see where it might be handy to use the drive curve to affect the starting point, so you should submit a bug report and get it fixed. While a drive curve doesn't change the overall outcome of a toolpath on a closed loop, as I suspected, it does provide that one additional bit of control that would be nice.

Another thing is that the drive curve can be selected using constant Z option, and you can also change the start point on the constant Z geometry as well, so you don't necessarily have to use additional geometry for drive curves. The drive curve did reduce the height of the starting point of the feature, so keep in mind that there is a little less wrap around the top corner when using a drive curve vs. not using one. If you do the E.O. after a facing op, you might get a little bit more of a burr at the corner with the drive curves than you would without them, but that's just a guess.

[RAF.]

I made a quick similar model and tested it out. I get the same result you do, that the drive curve option for changing the start point does not affect where the toolpath starts. While I also get a very similar toolpath without the drive curve, I can see where it might be handy to use the drive curve to affect the starting point, so you should submit a bug report and get it fixed. While a drive curve doesn't change the overall outcome of a toolpath on a closed loop, as I suspected, it does provide that one additional bit of control that would be nice.

Another thing is that the drive curve can be selected using constant Z option, and you can also change the start point on the constant Z geometry as well, so you don't necessarily have to use additional geometry for drive curves. The drive curve did reduce the height of the starting point of the feature, so keep in mind that there is a little less wrap around the top corner when using a drive curve vs. not using one. If you do the E.O. after a facing op, you might get a little bit more of a burr at the corner with the drive curves than you would without them, but that's just a guess.

I'm getting some results with not right clicking OK after selecting new start position and just picking regenerate tool path. From what I have found is that a drive curve has to exist to be able to have the modify start point available, but I may be wrong.

What I'm trying to achieve is to not have a vertical line at the wall as in the attacted example.

[mmoe]

If you mean that it has to exist as a 2d contour geometry, then I would say no. I was able to move the start point graphic using the constant Z as the drive curve, but like you it didn't really have any effect on the toolpath as it should. Using constant Z as the drive curves seem to be behaving exactly the same as if I had 2d geometry.

For the second example you show, I might break that up with boundaries so that there is a top and bottom drive curve that forms more of a "U" shape, for the radius edge, then use a pencil feature to do the fillet. It's still my opinion that drive curves are more intended to work on open contours, not closed contours, where you're using them more as a boundary with a start point. I imagine they didn't really test that out if they thought the contours would typically be open, and the start point option might have been more for picking one end of the contour or the other to determine which direction you intended it to follow along the drive curve. On a closed contour, the start and end point are probably viewed as the same position, and the rest of the intersections may not be considered a valid start point even though the arrow will stick to them (if that makes sense). It's much more obvious with an open contour as to where the start point can be as there is no adjacent geometry. Using a boundary to stop the E.O. toolpath from getting all the way to the fillet and having the inner and outer drive curve represent the top and bottom of that radius edge would probably eliminate the vertical motions. If I have some time later tonight, I'll model something up and experiment a bit. I'm off to coach some kids hockey for now!

[jrmach]

Is this just for practice,or is this for real ?
Charge accordingly if for real.

[RAF.]

Just trying to get the new Equidistant Offset options dialed.

Mainly to see if they will cut run time down when cutting next to a wall.

[mmoe]

Just trying to get the new Equidistant Offset options dialed.

Mainly to see if they will cut run time down when cutting next to a wall.

I don't think you're going to find that it's much different in that application or that it saves much time that way. I think it's more for machining between two curves rather than inside of what's essentially a boundary as you're using it, particularly where the curves are parallel. It eliminates much of the rapid motions in those scenarios and also eliminates the turn arounds across the part by running over the edge and turning around in a zig zag. For this kind of part, drive curves are the cat's meow.

Bobcad V26-V27 Comparison Drive Curves by mmoe5150, on Flickr

[mmoe]

Rapids are greatly reduced in this kind of part:

Bobcad V26-V27 Comparison Drive Curves3 by mmoe5150, on Flickr


The smoothness of the toolpath should also be considerably better since the tool never changes hard directions as it did in V26, which I think will improve finish quality for this kind of work:

Bobcad V26-V27 Comparison Drive Curves2 by mmoe5150, on Flickr

[RAF.]

mmoe

Thanks very much that is some nice info on the improvements for that type of work.

Thanks again

RAF