Wrapping Question?

Topics related to wrapped rotary machining in Aspire or VCarve Pro
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Kubotaman
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Wrapping Question?

Post by Kubotaman »

Okay I know this is most likely an Aspire question but here goes. I am making a acorn on my indexer and have a question. When it is in the final stages of using a .125 ballnose bit it will turn 360 degrees then reverse and do another 360 degrees. The z axis then raises .5 inch then goes down to the wood surface and then proceeds to cut in one direction then reverses itself and then raises again. It does this for the whole time it is cutting the final cut. Is there a way to stop the raising of the z axis and proceed to cut without raising the z axis? Why does Aspire make it reverse itself while cutting instead of just Turning the z axis constantly in one direction which to my opinion would take half as much time. Anyone have the answers?

Greolt
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Re: Wrapping Question?

Post by Greolt »

Kubotaman

This sounds to me like a result of the type of toolpath you are producing before wrapping.

Wrapping being just a post process applied to an existing toolpath.

Can you post the .crv3d file so we can take a look.

Greg

tmerrill
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Re: Wrapping Question?

Post by tmerrill »

Daryl,

In the flat world if an edge of a 3D component matches the material edge or goes beyond it, you will get the retracts to the Safe Z for safety reasons. In the picture below the left side of the top model goes slightly beyond the edge of the material and you can see the retracts to Safe Z in the blue toolpath. The right side, and the second model, are safely within the material and you don't see any retracts.

Try to increase your material size or position your model better in the material. Based on what Greg said, you could simulate your finish pass on the flat model and if you don't see any retracts, they won't be there for the rotary toolpath.

Tim
Attachments
Finish pass and material size.jpg

Kubotaman
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Re: Wrapping Question?

Post by Kubotaman »

Tim I will look at my drawing tomorrow to see if I have the material and model the same size. Thank you for the response. Is it possible then to cut a complete 3D model on a rotary wrap without the z axis rising? The rising of the z axis sure makes for a long time to cut.

tmerrill
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Re: Wrapping Question?

Post by tmerrill »

Hi Daryl,

I don't do rotary machining and very possibly misunderstood your question. I'll let someone with rotary experience take it from here.

If you can post the file as Greg suggested, it would be a big help.

Tim

moto633
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Re: Wrapping Question?

Post by moto633 »

Hey Daryl,
Yes it is possible to cut in the rotary with out the tool lifting. It is just like working in the flat just spinning!! You need to look your tool pathing over before you take it to mill to check the things Tim has pointed out.

Just think and watch what it does in the flat and use that same thought carried into the wrapping.

Hope that made some sence!
Nick

Kubotaman
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Re: Wrapping Question?

Post by Kubotaman »

Okay I am now starting to understand what I did wrong with my toolpathing. I take it that when my Z axis rises and reverses itself is because my 3D model is too long for the material size. I understand now. Then it is then possible to cut my model not only by not raising the Z azis but also not reversing itself because of it's raising. Hope I am making myself clear.

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dealguy11
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Re: Wrapping Question?

Post by dealguy11 »

I assume from your question that you're rastering in a direction so that the raster goes around the part, rather than the length of the part. If so, then you can get the tool to stop lifting as others have replied by carefully making sure the cutting path is inside the edges of the part. If you make this change, and you end up with a small area of uncut material, this can be addressed by changing the material setup so that the dimension that wraps around the a-axis (or whatever you call your turning axis) is just a little bit longer - maybe a quarter inch or so. Keep the cutting path just inside this larger area - you should now see when you cut it that the tool overlaps slightly at each end of the path as it goes around the part, eliminating the uncut material.

The other behavior you mention (turning 360 degrees one direction, then 360 degrees the other) is normal. Remember, it's rastering. In a normal flat raster, the cutter cuts one direction, then the other as it goes back and forth across the part. In this case, you've just wrapped one dimension around an axis. It's going to cut one direction, then reverse and cut the other.
Steve Godding
Not all who wander (or wonder) are lost

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