Roughing pass or no roughing pass for 3D project

[Bill George]

Do a quick Search on google and you will have your answer in less than 10 sec's., no need for a Thread.

[Jim Becker]

Okay, feed my ignorance please at the risk of hijacking the thread which I don't want to do. What is the "raster"? I saw that in the settings on Vectric and avoided it because well I didn't want to let Pandora out of her box. IF I need to do a separate thread say so.

When you use the pocket tool path in Vectric software, you have two choices for the "motion of the tooling" to cut out the material...Offset and Raster.

Offset has the tool start in the middle of the shape and work its way outward to the edges "in the shape" of the vector border, moving over with the requested stepover in the tool settings. The finishing pass is integral as the tool reaches the edge of the shape.

Raster causes the tool to move back and forth in straight lines, moving over with the requested requested stepover value in the tool settings. Raster cutting has options for changing the direction of the motion so you can follow the x-axis or the y-axis exactly or at any angle you wish relative to them. I often choose the angle that provides the "longest stroke" to cut fasters by taking advantage of acceleration) Raster also allows you to do a finishing pass around the perimeter of the vector, either before or after hogging out the material...or not at all. Most times, a finishing pass is done at the end of the material removal to clean up the little bit left. That's typically more efficient than doing it initially, but there's conceivably a reason where one might want to do it first I suppose.

The angle feature with raster cutting a pocket is what we take advantage of for the background effects I detailed in my most previous post in this thread.

BTW, cutting 3D shapes like the OP did can also leverage either Offset or Raster movement...cutting 3D is, if you think about it, a pocketing operation. It just has a variable depth, rather than a fixed depth.

[Ronald Blue]

Thanks for the detailed explanation Jim. I will experiment when it seems like a good place for it. I was experimenting with a 3d bird not long ago in VCarve photo and it ran at an angle rather than true to the X or Y axis. It automatically chose the most efficient cutting method for the tool paths which happened to be at an angle.

[Jim Becker]

VCarve Photo has some specialized capabilities that allow it to optimize for an image so that then end result is most accurate. When cutting "regular" 3D, 2.5F and 2D work, the decision is left to us to choose what we think will produce the best end result and/or be more efficient. Sometimes grain direction will matter. Sometimes it's about having "longer strokes" so that the machine can accelerate. I often try to accommodate both by orienting the stock so that both grain and distance can be optimized. After awhile, you start to get a feel for these things and they become habits.

[Brad Shipton]

Some of this will boil down to how many bits you want to go thru testing it. To me, it looks like the depth of cut is about 3/4". It will be the first plunges you would need to be most concerned with. If your first passes need to go to the max depth I suspect you could break a bit. Once you have made that pass and are only dealing with the small stepover, maybe it will work. That said, I have not tried this as I have always used the roughing pass. I agree with Mark. Use a larger hogging bit and speed it up. I usually use a 0.02" allowance in a single pass, but if you really want to fine tune the time you could increase the allowance so you reduce the z axis travel time. I have not broke any bits carving so far. I never find the roughing pass to be the problem for cut times and I have done a few pieces that took 36hrs to cut.

Adjusting your angle of cut for the one textured pattern will result in a cleaner profile, but you would have to consider how that might work for the reminder.