Need Help Machining contour elevation paths on a CNC router

[B-M0]

I am working on a project where we are attempting to machine a water droplet wave effect into a piece of wood. I was hoping to come up with a way to machine it all at once, but with each pass following a contour line, a specific "elevation" like on a map.
Typically the router path would be parallel lines, the tool head moving in the Z axis as it goes along the relief. We are looking to do the water effect with one pass with a large tool as we are removing a lot of material, and using that method will create very distorted shapes.
I figure if I can get the tool paths to follow the contours at a static Z height, like the contour lines on a topographic map, the circular shapes and water effect would be preserved. And would maintain a decent runtime. Anyone ever done anything like this?

 

[MikePro]

unless you have a toolbit that has the profile of the waterdroplet "waves", you wouldn't be able to do this manually by setting an engrave path to offsetting circular lines.... but if you did, then you could just set those engrave paths at increasing depths.

to accomplis this, most people have 3D toolpathing software such as

that allows them to create a relief (3D shape) in the software, and upon exporting the hatchfill/islandfill, the software automatically generates the "topographical map" of toolpaths at their respective depths.

 

[B-M0]

I am actually using Enroute, and have been playing with the relief cutting. Like that video though, I can only get paths that are linear. I'm attempting to create a path that starts at the highest point, and cuts a "ring" at increasing deeper depths. I'm thinking I may have to slice the 3D model into layers, and get a profile from each of those.
This is the pattern that I am attempting to cut: https://imgur.com/c27YyPh
Thanks for the help so far!

 

[MikePro]

I'm currently learning the software as well.... the tutorial video option is awesome, but I definitely wish there was a bigger library of start-to-finish job applications.

if you want it to "fill" along the path, instead of traveling only across the x or y axis, use an island fill. both accomplish the "same" thing, but hatch fill is linear while island fill is radial.

 

[B-M0]

When I do an island fill, applied to the contour, I get this: https://imgur.com/iBspwpx
I am hoping to get something like this: https://imgur.com/9pwEh3N

 

[astro8]

EnRoute can't merge/combine toolpaths as far as I am aware. I haven't put a great deal of thought into but I think the only way to get something approaching what you are trying to achieve is to mask each water droplet relief and apply a spiral toolpath unless you want to manually draw in each z contour.
The mask must follow the along the intersection of where each droplet intersects the adjacent one or ones. You would also need to overcut each mask by the radius of the toolbit. It would be a lot of work to get your file to where you want it.
You might look for a program that can produce topographical maps off a 3d model and use the contours off that. There's a setting in EnRoute to 'follow contour' so the tool will follow the contours even if they vary in z height.
I hope someone pipes up and sets us straight that it can be done more simply.

Just came back as I had a thought...you could slice it up and get contours off the slices and then stack them...put each stack on it's own layer and then cut by layer. you would have to experiment a little in your preview to see what amount are acceptable.

I tried it, works perfectly. You don't need to put on separate layers, just use 'engrave' and tick 'follow contour'. EnRoute is an amazing piece of software.

 

[B-M0]

I was heading down a similar path. I sliced my sample piece into layers, but was exporting a separate dxf for each level, importing into EnRoute, and assigning each a corresponding cut depth.
With your method, are you saying your file you input into enroute is 3D (each profile at a different depth), thus you didn't have to input a cut depth for each contour? I am not familiar with cutting by layer, or much experience with engrave toolpaths that follow contour.
Thanks a lot for digging into this Astro8. Your help is much appreciated.

 

[B-M0]

I think i figured it out: Import the 3D surface, apply relief mesh to it, "extract layers" from the surface, then engrave applied to contour.
Now I just need a faster computer. It is quite bogged down by the number of contours, and that is just with my small test sample. Need to be able to do it on 4'x6' area...

 

[astro8]

Yes, that's it. You can get rid of the relief and put each 'layer' of contours onto a new layer to help speed it up.

 

[Martin Denton]

Have a look at V Carve Pro by vectric, https://www.vectric.com/ they have a free trial edition. I know this will allow you to create a toolpath that starts at one depth and finishes at another along its path, the type of path you might create for draining board flutes etc... just switched over to it from Artcam and so far seems a very reasonably priced and powerful piece of software...

 

[B-M0]

First test a success (mostly). https://imgur.com/a/ZH3RbHt It's looking great!
There was some redundancy in the tool paths for some reason, so it took a lot longer to cut than necessary, but I'll be working on that today.
Thanks for the help everyone!

 

[Martin Denton]

So what program and method did you use ?

 

[astro8]

Check your pass count so that you are not cutting air passes, especially on the deeper cuts...you may have to adjust the tool parameters so that EnRoute doesn't split it into multiple passes per depth.

 

[MikePro]

that looks AWESOME! the layering effect is making me dizzy but I can't stop staring at it

 

[B-M0]

Anyone who is familiar with enroute know how I could get rid of the perimeter passes? https://imgur.com/a/m1TootW
When I do the layer extraction and then create an engrave, follow contour router path, it also includes the outer edge of the original mesh relief. I wouldn't mind this if it was the perimeter I wanted, but it's actually not very accurate. At each layer the path varies slightly, from a top down view. For now I dealt with it by extending the surface outside where I actually want the block cut out, and then doing a perimeter cut.

 

[astro8]

Off the top of my head...you can select them and delete them, edit them with the 'edit points', 'linearize tool', or the 'cut by line' tool, group, ungroup, whatever, before you apply a tool path. If you already have a tool path applied, EnRoute will group an inner and outer contour together as if it's one contour.
If you can't see what you're doing clearly enough, because of the relief, make a new layer and copy the relief and contours and 'paste to active layer' so you have an exact copy sitting there, in the exact position as a backup. Delete the relief on your working model using 'delete relief' in the Surface Menu.

 

[B-M0]

I tried several of those things - editing points, cut by line, and ungrouping. I'm not familiar with the linearize tool or where to find it. Nothing seems to be able to interact with the extracted contours. I'm thinking maybe when you extract slices from a mesh relief, the contours are not the same as if you drew them directly or even imported a dxf.

 

[astro8]

Try it without any tool path applied and you can’t be in an isometric view.. only side or top view.

 

[B-M0]

I was trying it without tool path applied, and in a top view. One bit of progress I have made, if I keep ungrouping it, eventually it does. Then I can delete individual loops, but still can't modify points.
That's enough for now, I'm just dealing with the added machine time. Thanks!

 

[astro8]

If you don't delete the relief or move it to another layer you won't be able to select the contours with the 'edit points' tool...or modify it with any other tool...