New 3d user needs help with stars

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Mikehell
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Re: New 3d user needs help with stars

Post by Mikehell »

Stari wrote:
highpockets wrote:Use a ball nose bit for roughing and a smaller one for finishing. If the stars are so small that a small ball nose bit doesn't produce the desired results create vectors around each star then using a V-bit create a second finishing toolpath with all the vectors around the stars selected and using the Machining Boundary "Selected Vectors" you should get better detail with out carving the whole piece with a v-bit.

Hope this helps.
Heres what I came up with (that worked)
Pocket in the stars section with a .125 ball nose
Then the full flag gets finished with a .125 3deg tapered ball nose bit

only thing is the estimated time is enourmous so ill have to figure that out. Or just scale everything down.
Doing a 3D finish cut with a .125 ball nose always takes a lot of time. Nature of the beast. You can try setting the overlap to a larger amount. Typically 10% is used, bump it up to 20 or nore, until the results don't look good I've also found that if you do a roughing pass on the 3D that you can bump the feed rate up quite a bit more than usual, on the finish since it's not cutting much material at all. I've been in a rush and did a finish pass at 25% overlap at 5.5 inches/second with a .125 bit with success. Probably could have done even more.

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Adrian
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Re: New 3d user needs help with stars

Post by Adrian »

With 3D cuts the programmed feed rate is often way above the actual feed rate as there is so much movement in the Z that it constrains the overall speed.

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martin54
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Re: New 3d user needs help with stars

Post by martin54 »

You could also do it in sections using different sized tools, the main flag part probably doesn't need a particularly small bit so set up some vector boundaries & just machine the flag part using a largish tool, biggest you can that still gives the level of detail you require. Then machine the other part with the stars as a separate toolpath with a smaller bit :lol: :lol:

This is where the toolpath preview comes in really useful because you can sit & play around until you find what works best & you haven't wasted any material at all & can often save yourself hours of machining time :lol: :lol:

Stari
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Re: New 3d user needs help with stars

Post by Stari »

martin54 wrote:You could also do it in sections using different sized tools, the main flag part probably doesn't need a particularly small bit so set up some vector boundaries & just machine the flag part using a largish tool, biggest you can that still gives the level of detail you require. Then machine the other part with the stars as a separate toolpath with a smaller bit :lol: :lol:

This is where the toolpath preview comes in really useful because you can sit & play around until you find what works best & you haven't wasted any material at all & can often save yourself hours of machining time :lol: :lol:
I did separate the stars section from the rest. I still have to mess with it but I'd like to get one knocked out before July 4th. Well see what happens.

I'm pretty satisfied with the stars that stick out instead of engraved but I messed with it last night with the comment about doing a rough 3d then a finishing with a smaller ball nose. And if the stars didn't come out right try a finishing pass with the stars vectored.

Still kind of blotchy but maybe I need to use a 40deg vbit or something.

Stari
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Re: New 3d user needs help with stars

Post by Stari »

martin54 wrote:When you are setting up the toolpath for the stars from the vectors you have drawn are you checking the box to project the toolpath onto the 3d model as Adrian suggested at the top of the page ?
Yep! I think I just need to mess with it a little more. I adjusted the depth last night messing with it and seemed to come out a little better but had to get some sleep. So maybe we'll see later today.

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