Problem with cut file on 3d model

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sailfl
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Problem with cut file on 3d model

Post by sailfl »

I have a medallion that is 24" in diameter. I have created an outside circle that is 24.25" in diameter and an inside circle that is 14.5" in diameter. I have been trying some different cut files to see the difference in the cuts. I only want to cut the area between the outside circle and the inside circle.

The first finish tool paths that I tried cut from the center outward. More recently when I try a finish tool path, the cut start in the middle of the area and works outward. When it is done with that it cuts the inside.

I do not want it to do this. I have not changed any settings.

Why is it doing this and what do I do to fix this?

Thank you for any help.

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Adrian
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Re: Problem with cut file on 3d model

Post by Adrian »

You need to have vectors defining the area that you want the finishing/roughing cuts to process selected when you click Calculate on those toolpaths.

In your case select the inner and outer circles. Hold shift down while clicking to select multiple vectors.

sailfl
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Re: Problem with cut file on 3d model

Post by sailfl »

I did define the area that I want to cut.

I have attached an example of what is happening. I can not included my customers file.

I am using the 3D finishing toolpath. I wanted to attach the image from the Aspire but the forum will not allow bitmap images the program creates.
Attachments
3D Finish Cutting Problem.crv3d
(285.5 KiB) Downloaded 161 times

tmerrill
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Re: Problem with cut file on 3d model

Post by tmerrill »

Hi Nils,

You didn't include any toolpaths in your file so I did a quick example for myself.

You can sometimes change the behavior of the 3D Finish toolpath using an offset strategy by slightly changing the bit's stepover a very small amount. For example, instead of using 8.0% try 7.9% or 8.1%. Recalculate and preview to see if it changes to what you want.

Using your vectors placed over a simple planar 3D surface I could make it finish from inner boundary out to outer boundary using this trick.

If this doesn't work for you can you post a better file, one with a 3D surface and a calculated finish toolpath?

Tim

sailfl
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Re: Problem with cut file on 3d model

Post by sailfl »

Tim,

I can understand it starting from the inner defined circle and moving to the outer defined circle or reversing direction, but to start in the middle of the cut of the defined area does not make sense to me.

I have been trying some different stepover numbers but I have not seen any change in behavior.

Thanks

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Ms Wolffie
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Re: Problem with cut file on 3d model

Post by Ms Wolffie »

Hi Nils
Is this what you are trying to do?
Curlicues.jpg
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Wolffie
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tmerrill
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Re: Problem with cut file on 3d model

Post by tmerrill »

but to start in the middle of the cut of the defined area does not make sense to me
The reason it does this on the offset strategy is because the program allows you to select a climb or conventional cut. For a situation like this, the only regions affected by climb or conventional will be the inner and outer vertical edges. So by starting in the middle it will perform one half in a direction that ensures your choice of climb or conventional direction against the outer vertical edge and then reverses to ensure the same climb or conventional direction against the inner vertical edge. If it didn't do this, I'm sure someone would be upset because they specified climb or conventional and the two edges are cut different.

My little trick may be exploiting a weakness in Aspire, which is why I'm wishing I hadn't said anything as it may get fixed now :(

I can still change the toolpath with my simple file. If you can, actually post a file you can share with a toolpath in it and let us take a look.

Tim

sailfl
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Re: Problem with cut file on 3d model

Post by sailfl »

Tim,

The outer circle is at the outer limit of the model.

But I have cut files I created that it cut correctly. Started from the inner circle and cut outward to the outer circle. I started to have problems when I wanted to try different stepover values but I didn't want to use the same finish toolpath.

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