Michael,

"Thanks Michael for the idea on ZSurf. Producing surface maps is one of the things I need to do. My CAM program produces cut path information based on a surface map."

I was just indicating that ZSurf will more than likely work. The Chinese characters are scanned in after being hand drawn. I can then run them through ZSurf to produce the height maps and then import them either directly into my CAM program or bring them into MOI and then export to .STL.

I will try the Construct / Offset command. Since I posted I have also been playing around with the Transform/Scale command as well.

Thanks

Joe

Hi Joe,

> I was just indicating that ZSurf will more than likely work.

That's good news because that's a lot less work! :)

When you use the ZSurf approach you don't draw any curves at all, it just takes the image directly.

The main download for ZSurf is here:
http://mwt.net/~sjedging/ZSURF4.zip

To use it with your character image, you need to resize the image to be less than 1600x1600 in width and height, and save it as a BMP format image (it needs to be saved as a full color image). Then it can be loaded into ZSurf, and when you hit the run button, it will cook up a file in the in the same folder as ZSurf4.exe named srf.igs - that file can then be loaded into MoI.

I think that you'll also need to hit the "invert" option inside of ZSurf, either that or invert the colors when you save them as a BMP file.


> Since I posted I have also been playing around with the
> Transform/Scale command as well.

Yeah scaling is different from offsetting. You can't produce an evenly spaced result just from scaling alone except in special cases like a circle.

- Michael

Hi Pilu,

No problem with *.eps ;)

Open in INKSCAPE -> BMP trace -> Save as *.eps
Open/import this *.eps with Moi3D -> edit and extrude....in minutes.

I have attached the (raw) *. eps file

I would recommend to use Petr's RebuildCurve(s) Script after importing your .eps... http://moi3d.com/forum/index.php?webtag=MOI&msg=2776.1

Hi Joe,
I had another idea that can be good to create a surface for the character shape.

You can use the array to path function and create the wall shape as you want, then do some curve trimming to clean up and reshape the areas that bunch together. In the real tight corners, you can do some extra ops like sweep and network with those generated curves to fill those in.

So, draw your profile on the path:





Then array on path:




Then move into these areas and work the curves to create a smooth transition here:




Possible trims....Lofts....Sweep....Networks.

THe other thing to remember is if you are camming many of these, a 3d toolpath will be a much longer more intense job. 2d operations are preferable when applicable. If you array enough around the path to match a step amount, you could use a profile operation to create the edge. (many small curves) Or you could then trim these generated curves in the front view, with a few different levels in the Z direction, then connect those trim points with a curve to generate multiple curve paths that follow that surface curvature. Then again a profile cut in the cam package.

Let me know if I didnt make sense and I can Illustrate better.

BurrMan,

That is very interesting. I did not think about using the array command. Still way too new with MOI.

When you indicate to use more 2D operations, I would assume you are referring to the flat sections of the curves.

What is curve trimming?

Thanks

Joe

Pilou,

What would be the advantages of using inkscape? Can inkscape perform height maps?

Thanks

Joe

No limite of size ;)

Thanks Pilou

Joe

Looks like Zsurf is a nice companion to MoI when certain organic shapes are needed.

As a jeweler, I'd love to be able to create a 3D design in Zsurf on a rectangle, then be able to wrap it around a cylinder (ring) in MoI.

For example, I want to create a render of a ring with a hammered finish, without using a bump map. For close up renders, you can't beat having the actual geometry.

Ed

Hi Joe,
THe 2d operations comment in it's simplist form would be to take just the curve you extrudued and run a profile operation with a corner radius tool on the upper edge of the geometry to create the edge surface. So one profile cut to extract the shape out of a block then the second to get the fillet.

I'll post some more details about the other stuff in just a bit.

Hi Ed,

> As a jeweler, I'd love to be able to create a 3D design in Zsurf on a
> rectangle, then be able to wrap it around a cylinder (ring) in MoI.

Actually ZSurf has some options such as using a cylinder for the base surface instead of only a flat plane, which sounds like it would do what you want here.

Check out this previous thread for an example:
http://moi3d.com/forum/index.php?webtag=MOI&msg=636.7

- Michael

Hi Joe,
The trimming I was refering to is, if you do a curve array, in the tight corners you'll end up with what looks like this:



If you select these:



Then run the "Trim" command from the edit menu, it will look like this:



You can hit done or right click to accept and leave all the pieces there, then go in and delete what would be overlapping pieces:



Then you end up with more manageble/workable curves:



With these curves you can do some extra work to get your surface through those tight areas.





THe other thing I mentioned was about trying to do it with 2d operations. If you did the stepover math and knew how many levels you would need to get a clean surface cut by doing level profile cuts with a ball mill or something, you could go to a front view and array a bunch of "levels" up in the Z direction.



THen you could trim those curves with these level lines and get a result like this:



This would give you segments at various points on those curves that would have "end snap points" on them:



I could then use the curve through points command to draw curves by snapping to the endpoints of each individual section:



BTW: I used the new MoI scene browser to assign a style to each level. THen I could hide all others and work with one level at a time.


Or I could pick each level seperatly and loft just those little short pieces (It works better than trying to do the entire large curves that bunch up more) to create a surface, then join them all together for the larger surface that I can do a 3d toolpath on:



Just a note: the last lofted surface picture is deceiving in that it wouldnt be just a straight forward loft. I would have to fix a few areas where the gaps were not well defined to keep the loft going in the right direction.

Still with a bit of practice, MoI will do anything you want it to do!

Hope that helps a bit and didnt just make it more confusing.

Burr

And of course, just using your tooling to cut the profile alone produces a nice charater shape!

Thanks Michael - I'm going to try making a relief pattern in Zsurf on a cylinder, then boolean it with a same-size ring in MoI.

That posting you referenced is two years old. Two years ago I didn't even know how to spell MoI :)

There's some good information in those older posts. I'll need to find time to read back through the forum.

Ed

Thanks Burr,

Way cool. I really appreciate you taking the time to explain all of this. Would you connect the points on the flat surface or would you use a command like Network or Blend to fill in the center of the character?

Thanks

Joe

Hi Ed,

> Thanks Michael - I'm going to try making a relief pattern in
> Zsurf on a cylinder, then boolean it with a same-size ring in MoI.

One note on this - since you will be dealing with an open surface with the ZSurf generated bit, you may need to use the Trim command to cut the cylinder and leave a hole, then use Join to glue the pieces together, rather than using booleans.

Booleans are more oriented towards working on volumes, so they may not understand which pieces to keep and remove automatically if you are working on open surfaces.

But Trim works on the surface skin of objects only so it's more what you use (along with Join at the end) when you're working on surfaces instead of volumes.

- Michael

Hi Joe,
The idea for creating the Z level curves would be to use them in your cam package as profile operations. No surfacing.

But with the smaller increments, things like lofting between those curves may work much better. (I didnt test it though)

If you just wanted to see the model through to the end in 3d, then "Planar" would fill in the top (All points need to be level in Z)

Hi Burr,

My cnc system uses proprietary software and cuts complex curves as raster lines. (CarveWright) I will have to play around and see if I can get it to cut a profile by using a series of vector lines. As a result I will more than likely have to use planar to fill in as a solid. Any difference in depth would be picked up and possibly affect the height map.

You did mention that there was a step over formula to calculate width and height of cut based on tool diameter? What would be the correct name of this formula that I could google.

I have tried tool bit step over and step over formula.

Thanks

Joe

Hi Joe,
So can Carvewright create a toolpath from this?



If so, then I was suggesting making curves from those sections that would look like this




Then when you cut each curve, it would cut at its own depth and create a "step".



This is the step I was talking about.




If the part is 1 inch high, and the spacing of each level is .8 and you use a .5 ballnose cutter, then the ridges in between each level will be at some hight. The more levels, or curves, the finer the step and the smoother the surface (The longer the cut time). Less curves and levels is faster cut time, then you just pull the piece off the machine and do a quick sand or grind to smoth the toolpath edges away.

It's not a formula I mentioned, just a decision to be made on how you want to cut it.

Also, after doing some experimenting with this to show you, it becomes more apparent that it's harder to implement than I'm making it sound. It would require working the curves a bit to get a good profile. May be better off just going the hieghtmap software route.