Boundary Vector

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angelosart
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Boundary Vector

Post by angelosart »

Hello,

Not sure if I am the only one with this issue or I should not be concerned about this. However I am looking for extremely accurate cut.

When I create a boundary vector around a component, the boundary is off and does not follow the component's edge. Its off about .006 to .01 on all sides.

See photo attached
Boundary Vector off
Boundary Vector off
Also the size of the component and the size of the boundary vector are different. The component is 1.8227 width and the boundary vector is 1.8196. A .003 difference. Shouldn't they be the same?

Any thoughts?

Thanks
Angelo

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TReischl
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Re: Boundary Vector

Post by TReischl »

Has to do with the system being based on "pixels", for lack of a better term. In other words the lines we draw may not fall on the "pixel" boundaries all nice and neat like. So discrepancies show up.

A thing to remember, Aspire is not sold as a solid/mechanical modeler, it is designed for artistic things so a few thousandths of an inch do not matter. But of course, we all decide to do mechanical things that need to be spot on so then the trouble starts.

When I do real mechanical stuff that needs to be spot on I turn to a couple of different programs, Fusion is one and I also use something called Hexagon which is no longer around. Fusion works extremely well and is free unless you are a certain size business. It also has a serious learning curve.

So, whatchya making?
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angelosart
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Re: Boundary Vector

Post by angelosart »

TReishl,

Thanks for the reply. It was what I expected. I am trying to make a zig zag chair and I need 22.5 angles and I need the profile to be dead on. My first attempt was off a little and I thought the boundary vector might be one of the culprits. I guess I'll just adjust the boundary vector manually so it lines up.
5654553_s.jpg

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Rcnewcomb
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Re: Boundary Vector

Post by Rcnewcomb »

I am trying to make a zig zag chair and I need 22.5 angles and I need the profile to be dead on.
Do this with 2D toolpaths. It will be faster and more accurate.
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dealguy11
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Re: Boundary Vector

Post by dealguy11 »

Second the suggestion to use 2d vectors. No reason for any 3d on this chair that I can see.
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angelosart
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Re: Boundary Vector

Post by angelosart »

Thanks for the 2D suggestions. Can you help me as to how I can get a 22.5 degree angle using 2D?

I need two 22.5 degree angles to make a 45 degree outside angle. See photo below...
22.5 angle.jpg
22.5 angle.jpg (4.12 KiB) Viewed 3043 times

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Adrian
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Re: Boundary Vector

Post by Adrian »

Use the polyline tool to draw the angle directly or draw a line and use the rotate tool and join it. Lots of ways to do it.

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adze_cnc
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Re: Boundary Vector

Post by adze_cnc »

angelosart wrote:Thanks for the 2D suggestions. Can you help me as to how I can get a 22.5 degree angle using 2D?
I lieu of using a tablesaw for this project how about a 135 degree V-bit and cut "on the line"?

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jimwill2
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Re: Boundary Vector

Post by jimwill2 »

Moulding toolpath?
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mtylerfl
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Re: Boundary Vector

Post by mtylerfl »

I just want to see a video of the first “big guy” sitting on the chair and leaning back!

:shock:
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angelosart
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Re: Boundary Vector

Post by angelosart »

Sorry guys, I didn't explain myself well enough. The 22.5 degree joint runs along the end grain. That's why I figured to go 3d on a cnc. See photo below. I'm using Bamboo plywood. I'm probably just going to back to the table saw.
IMG_3046.JPG
The chair design is by Gerit Rietveld, Dutch designer.

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dealguy11
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Re: Boundary Vector

Post by dealguy11 »

So it's just an edge miter? Yes, table saw would be a good option. If you want to do it on the CNC, then it would be better to do it as a 2d path with a 45 degree v-bit, if you can find one with a large enough diameter. Would be much faster and give a better finish on the part than running a 3d path.
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4DThinker
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Re: Boundary Vector

Post by 4DThinker »

Easy to do with the Moulding toolpath if you can draw a side profile of the 22.5 angle. Example attached.
22.5 moulding toolpath.jpg
You may need to sand the bottom sharp end a bit.
4D
Attachments
22.5 moulding edge 4D.crv
(50 KiB) Downloaded 87 times

angelosart
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Re: Boundary Vector

Post by angelosart »

4D,

I'm assuming you have version 9 with the molding toolpath. Unfortunately I have version 8 but thanks for sending the attachment anyway.

A

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Re: Boundary Vector

Post by 4DThinker »

In that case, you could use the fluting toolpath. A parallel row of closely spaced short vectors , offset by 1/2 the diameter of the bit used.
Example .CRV file from VCarve 7.5 should open in version 8. I used a 1/4" end mill, and vector 1/16" apart. Vectors all start at the top of the slope and end at the bottom. The array tool was used to copy them after I just drew one. Again, a little drafting was needed to determine how long the lines needed to be.
Fluting 22.5.jpg
Attachments
22.5 slope Fluting 4D.crv
(165 KiB) Downloaded 88 times

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