PhotoVCarve question

[denver]

Hello,

I'm sure this can be done, I'm just not sure exactly how to do it. What I would like to do is use an end mill for the area clear, then a V bit for carving the leaves, and doing the inside edges of the border. That would leave a smooth surface on the bottom without taking a long time and minimize the V bit work.

If I start with the image file and PhotoVCarve, it is going to do everything with the V bit, which is going to take a long time. And I expect the bottom surface is going to be rough even if I use very close line spacing.

This is more or less a learning experiment, so proportions and dimensions can easily change. I just picked these because they were simple. And the material will probably be wood, or wood product.


Thanks,

Denver


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[paco]

So you want a recessed panel like this...


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and want to do what with the oak leaves? Etching or 3D relief? Photo V Carve only etch/engrave (or alike).

If you want to etch the image in the recess, you need Photo V Carve to program the etching part and V Carve PRO to create the recessed panel AND place the etching exactly where you want. Can you do both separately? Etching the image will require precise Z positioning...

[denver]

Hi Paco, you're almost correct. I want the oak leaves raised, about 1/2 the distance of the recess. Does that make sense?

Thanks,

Denver

[paco]

Etch or 3D relief like this (http://www.vectorart3d.com/store/index.cfm?Fuseaction=Detail&ID=50055).

[denver]

This is approximately what it would look like. The second image shows a little of how part of the cross-section might look.

I suppose I could recess down to where the top surface of the leaves would be, then use PhotoVCarve to do the rest. Just seems like a lot of material to remove with a V bit, and it would be slow and probably leave a rough surface on the bottom.



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[paco]

I don't have Photo V Carve installed by now; can you have an outline of the PVC file once into VCP? If you have an outline (or find a way to have one, you could use that to packet around your leaves design and inside the recess bevel...

Does that make sense? Do you have V Carve PRO (VCP)?

[denver]

Yes, I have VCP. I had thought of extracting the outline and I think I can do that with gimp. But then I still have to get that converted to vector format. And XY positioning for that might be pretty tricky.

Maybe with the tools I have there isn't a good answer.

[paco]

Make the whole etch in PVC, save the file but don't fuss with saving SBP toolpath file (just create the toolpaths(s)). Now open VCP and import the PVC file into VCP. Does that get you an outline? Maybe from that point it'll be easy to create one with the drawing tools of VCP... maybe you'll always get into selection mode... I know Cut3D get to one once into VCP but I'm unsure as for PVC... Once the PVC file is imported into VCP, you can position it wherever you want. As regarding the overall depths of your project, I'm not sure of what you want exactly...

Does that help? I'll see if I can get a moment to install my seat of PVC and play with it... been a moment since beta testing this program...

[paco]

If you cannot trace over you PVC import in VCP, you could trace around the original image in whatever software that can do it (Inkscape, COREL, Rhino) and import the vector(s) next into VCP... for machining purpose you want a nice flowing curve, not jaggy outline...

[bleeth]

I don't know about v-carve pro, but if you can just carve the leaves in it and have a vector definition for the edges of the leaves, you can do the rest with Part Wizard easily.

[denver]

Paco, PVC saves .pvc files. VCP reads .crv, .dxf, .eps, .ai, and .pdf. You would think that two products from the same place would be able to exchange files.

Dave, I guess that's part of where I was getting stuck: the vector definition for the edges of the leaves. Once I have that, I can do an area clear with PW or VCP, then carve the leaf area with PVC. Hopefully everything would still match up.

I'll try creating an outline image with gimp, then tracing it with inkscape or by hand. That should give me a "plateau" of the correct shape. Then I can carve the image on that surface. Even if the "plateau" is a bit off in size or position, it probably won't be noticeable.

It's easy to picture the end result, but I'm not yet used to visualizing each step when multiple techniques need to be used.

Thanks,

Denver

[woody123]

Hi...Don't have a Shop Bot yet but soon hopefully...this is something I would like to do....would I be able to do this in Artcam or would price an issue as Artcam is much more expensive? thus V Carve P is a better option for starting out. Trying to pickup as much info as possible...excellent forum
Thanks
Woody

[paco]

Denver,

to get a *.pvc file into VCP, you need to IMPORT it... does that make sense? Unless you have a very old release, you can get your PVC file into VCP. File/Import.../ check out the file type drop-down box...

Why bother with GIMP (unless you need image editing) to trace on the image; trace the outline right into Inkscape and save as EPS by selection only of the traced curve(s).

...

I just happen to have a few PVC file around...


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you can trace on the imported PVC "without" problem. That's a PVC file imported into VCP 3.102 with some very accurate tracing from me... see, it import your PVC toolpath in the same time.

What's next?!

[denver]

Hah! The File Import was always grayed out, but now I see that it becomes active if I select "Create a new file" first. That changes things. I'll fiddle with this some more tomorrow and see what other difficulties I can get into.

Thanks,

Denver

[denver]

Ok, VCP imports the leaf file from PVC as a rectangular object, so when I do the pocketing, I end up with a rectangular block for where the leaves get carved. It looks like this:


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To get rid of the rectangle, I need the outline of the leaves, so I created one with inkscape, and saved it as a .dxf. Now I have a drawing that looks like this:


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However, VCP doesn't like the outline: it says it has open vectors and won't close them. PW doesn't have any trouble with it though. And they look ok in CAD.

I have to think about this some more.

Thanks,

Denver

[paco]

Study the outline vector(s) carefully under node edit mode and you'll find the problem. VCP can close the vector without problem. When programming the recess pocket select the leaves outline then the recess outline but not the PVC import.

Everything you want to do can be done in the wonderful environment of VCP.

[denver]

Ok, I didn't really see anything wrong with the end nodes of each segment, but I got them to join using one of the "Join" buttons on each break in turn until there were two segments left. Then the automatic join worked.

So I'll do all the pocketing then I can load the .pvc file and move that over the outline and do the carve, correct?

Thanks,

Denver

[paco]

Not if you want the leaves etching to be raised; draw the panel contour and the outer edge pocket (recess). Import the PVC design and position it exactly where you want it. Import and position the leaves outline. Now you can pocket with the outer edge recess AND the leaves outline vector(s).

At this moment, I think we'll spare the bevel for a next step... you can send me your CRV file and I could have a look at it and apply some of my ideas for you to study. I wouldn't want you to bypass such an opportunity to learn the softwares!




Let me know of what VCP release you have (Help/About).

[denver]

Very, very good! This is starting to look just like what I'm after. There seems to be a raised edge around the leaves, but I think I know why. I created the first pocket toolpath by selecting the inner border of the panel and the outline of the leaves (order of selection doesn't matter, does it?). I set the starting depth to zero, and the cut depth to 3/8". Then I made another pocket toolpath by selecting just the leaf outline, start depth zero, cut depth 3/16". Then I moved the v carve toolpath that came along with the .pvc leaf file to the bottom and edited it to start at a depth of 3/16".

The second pocket toolpath is going to stay inside the lines, while the first stays outside, so I end up with a slight raised edge in the preview. I could get rid of it by creating a profile toolpath to machine on the vector, but will this really be necessary? In reality, won't that edge be pretty thin and easy to remove, if it's there at all? Or is this theory all wrong, and the raised edge is because of something else?

In any case, this is way cool. It's a far cry from cutting plain flat parts.

The match between the leaves from PVC and the outline created from an entirely different process is suprisingly close.

Paco, My VCP version is 3.102. I'll email you the file that produced this.

Thanks,

Denver




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[denver]

Ok, I figured out that those raised edges are from mis-matches between the outline of the leaves and the image from PVC. I need to adjust the sizes so the image is exactly the same size or slightly larger than the outline. Right now, the image is slightly smaller.

Also, is there some reason the default line angle in PVC is 30 degrees?

Thanks,

Denver

[paco]

Also, is there some reason the default line angle in PVC is 30 degrees?

I think that you can change that with your PVC file into PVC itself then re-import the changes in VCP.

[denver]

Yes, I saw where the line angle is set in PVC. Is 30 degrees a better choice than 90 degrees? Or something else?

[paco]

I'd say it is up to you... but I would recommend considering the material you are intending to use...

[denver]

Ok, I was just wondering.

Now, if I want the inside edges beveled so the inside corners are sharp, I'll need to do that with a V bit. I see two ways to accomplish this:
1. Make a second inner border and cut to that with the V bit. This would mean an additional toolpath. I can easily figure the necessary offset if I can remember the trig formulas, or just make a drawing and let my CAD software measure it for me.
2. When setting up the first pocket opertation, select v-carve instead of pocket, and specify a flat area clearance tool. Then I don't need a second border.

The first method would put the bevel on just the inner perimeter. The second would result in beveled edges for the leaves also.

Am I missing anything?

Thanks,

Denver

[paco]

I haven't got a real chance to study your file to be honest but one thing I've noticed soon is that the leaves outline create a lot of 3D sharpening corner movements... it would need some teak and smoothing.

Since you have different depth for the depth and the PVC, you need something "special" going on here; half the offset for the outline... I'll see if I get a chance to make some tests later... V bit carving strategy should do the trick but you may have to "trick" the software regarding the different depths.

This may appear quite a lot of trouble at first but I think you'll be learning a lot from this very specific goal to be achieve, with all it take, with what you have. Searching for solutions and trying things is going out of the box, doing more than what the package originally offer, choosing the red pill... I highly encourage you to further investigate. If you ever get to the point where you firmly believe it (something/whatever) cannot be done, then you know you'll reach the very limit of the software... which has a paradoxic {translation here} feeling related to; it's frustrating but it feel good in the brain! Keep at it!

[denver]

I tried running this today, and everything was mostly ok. There were several things that I noticed that are going to need some investigating.

First, each time it gets to the end of a line while doing the PVC import it moves to safe Z and back down. At least that's what it looks like to me. That adds about two seconds to each line, which adds up to a significant amount of time. There's no need for it to do that, but I don't know how to stop it.

The second thing is with PVC. I couldn't find a way to get it to ignore the background of the image. It always wanted to cut a little bit for that, also. That's another big waste of time, especially in this case. The background is white, so it should just leave that alone, but it doesn't.

And finally, there's a little mystery with the Z depth appearing to change. The large popcket is fine - very consistent and smooth. However, in the upper left corner area, where it does some intermittent pocketing, the bottom surface has some small areas that are higher than others. Not by a lot, but enough to see and feel. It's almost like it was going to make another pass over those spots, and forgot.

I haven't decided whether or not to bevel the edges of the leaves, but the bevel around the inside perimeter came out very nice.

Thanks,

Denver

[paco]

First, each time it gets to the end of a line while doing the PVC import it moves to safe Z and back down. At least that's what it looks like to me. That adds about two seconds to each line, which adds up to a significant amount of time. There's no need for it to do that, but I don't know how to stop it.
Maybe you can set the safe Z to very low for that part...

The second thing is with PVC. I couldn't find a way to get it to ignore the background of the image. It always wanted to cut a little bit for that, also. That's another big waste of time, especially in this case. The background is white, so it should just leave that alone, but it doesn't.
I believe there are some tutorials that emphasize on that aspect of etching/carving images... search around the VETRIC's Web site and maybe the VETRIC forum PVC threads...

And finally, there's a little mystery with the Z depth appearing to change. The large popcket is fine - very consistent and smooth. However, in the upper left corner area, where it does some intermittent pocketing, the bottom surface has some small areas that are higher than others. Not by a lot, but enough to see and feel. It's almost like it was going to make another pass over those spots, and forgot.
Make sure the material remain flat and that the hold down is solid... check the tool for play, bit slippage and such...

Do join in the VETRIC's user forum, you'll meet new poelpes!

[denver]

Haven't had much time to spend on this lately, but I did find out how to get it to ignore the background: use the "Make color transparent" in the "Load image" section of PVC. So that takes care of that one.

Still need to look into the other two, but won't be able to do much until late next week.

Thanks,

Denver