v bit depth on a graphic

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lestes
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v bit depth on a graphic

Post by lestes »

I know this is probably a dumb question but..... How does a v bit know how deep to cut on a graphic? Is it the darkness of the graphic parts? I imported a black and white graphic of a buffalo head and when I cut it there were very deep cuts and some that were just scratches. I was using a 90 degree v bit and vcarving it.
Thanks

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Adrian
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Re: v bit depth on a graphic

Post by Adrian »

It's the combination of the gap between the inner and out vectors and the angle of the bit. The further apart the vectors are from each other the more the tool will "drop" down. The more acute the angle of the bit the further it will drop with the same vector gap.

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gkas
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Re: v bit depth on a graphic

Post by gkas »

The V bit rides between two lines like rails. The wider apart, the deeper the cut. Wider angle bits cut shallower, narrow angles cut deeper. https://www.vectric.com/support/tutoria ... ng_Started

You can also cut 'on a single line', and specify how deep to cut. This is nice for borders, etc.

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adze_cnc
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Re: v bit depth on a graphic

Post by adze_cnc »

Adrian & gkas: I suspect this is actually a question about the "PhotoVCarving toolpath strategy" and not "V-carve / engraving"

Steven

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Adrian
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Re: v bit depth on a graphic

Post by Adrian »

Good point. Still haven't got used to that toolpath being in VCarve. Whenever someone says a cut with a v-bit I assume v-carve toolpath automatically.

If it is a photovcarve toolpath then the darker parts are cut deeper and the lighter parts shallower. If you're getting scratches rather than cuts then your z-zero setting method might be off. I haven't done one with VCarve/Aspire only with PhotoVCarve itself but I always got better results with 60 degree bits rather than 90.

lestes
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Re: v bit depth on a graphic

Post by lestes »

Thank you! I think I have it in my old head how this works. I haven't tried Photo carve yet. I am still trying to learn which bits do what. I am still very new to this and you all have been a great help.
Thanks

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Xxray
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Re: v bit depth on a graphic

Post by Xxray »

I have done dozens and dozens of lithos all using a small tapered ball nose bit and have had great success with it, I have yet to try a vbit. So there are more than 1 ways to skin a cat, with me I think its more a case of "if it ain't broke, then don't try to fix it" than anything else. My results are so good its hard to see how they can get better so I don't try.
On dark parts you won't get any depth at all so thats normal, if you think overall the image is too dark resulting in the dark parts being pure black and the lighter parts too dark then thats something you'd have to remedy using software to lighten the hue of image, keeping in mind that you want to avoid blazing white areas which would be a hazard to cut through the workpiece. This is assuming you are using corian, not clear if maybe you are trying wood or something.
Doug

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FixitMike
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Re: v bit depth on a graphic

Post by FixitMike »

Lots of useful information in Help-Help Contents at the top of each Vectric program page.
Good judgement comes from experience.
Experience comes from bad judgement.

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Adrian
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Re: v bit depth on a graphic

Post by Adrian »

Xxray wrote:I have done dozens and dozens of lithos all using a small tapered ball nose bit and have had great success with it, I have yet to try a vbit. So there are more than 1 ways to skin a cat, with me I think its more a case of "if it ain't broke, then don't try to fix it" than anything else. My results are so good its hard to see how they can get better so I don't try.
On dark parts you won't get any depth at all so thats normal, if you think overall the image is too dark resulting in the dark parts being pure black and the lighter parts too dark then thats something you'd have to remedy using software to lighten the hue of image, keeping in mind that you want to avoid blazing white areas which would be a hazard to cut through the workpiece. This is assuming you are using corian, not clear if maybe you are trying wood or something.
Lithopanes are the reverse of a standard PhotoVCarve toolpath though. With the v-bit engraving (the only thing you can do with the VCarve version of the toolpath) the dark areas are cut deepest.

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