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3626c gap - Printable Version

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3626c gap - Fredrik Hareide - 2024-03-12

I was making a pattern on 3626c today and noticed that there is a 0.2 gap between the faceplate and the rest of the part. Is this intentional?

Code:
1 16 0 0 0 1 0 0 0 1 0 0 0 1 s\3626cs01.dat
1 16 0 4 0 13 0 0 0 13 0 0 0 -13 2-4cyli.dat
1 16 0 4 0 0 0 -8 0 -6.4 0 -8 0 0 t04o6250.dat
1 16 0 4 0 8 0 0 0 -6.4 0 0 0 -8 t04o6250.dat
1 16 0 17 0 0 0 8 0 6.4 0 -8 0 0 t04o6250.dat
1 16 0 17 0 -8 0 0 0 6.4 0 0 0 -8 t04o6250.dat

The gap can actually be seen in plain text here as 6.4 will give 12.8 and not 13.
Edit: 
Gap is smaller than first anticipated. Might be ok?


RE: 3626c gap - Philippe Hurbain - 2024-03-12

(2024-03-12, 7:40)Fredrik Hareide Wrote: I was making a pattern on 3626c today and noticed that there is a 0.2 gap between the faceplate and the rest of the part. Is this intentional?

Code:
1 16 0 0 0 1 0 0 0 1 0 0 0 1 s\3626cs01.dat
1 16 0 4 0 13 0 0 0 13 0 0 0 -13 2-4cyli.dat
1 16 0 4 0 0 0 -8 0 -6.4 0 -8 0 0 t04o6250.dat
1 16 0 4 0 8 0 0 0 -6.4 0 0 0 -8 t04o6250.dat
1 16 0 17 0 0 0 8 0 6.4 0 -8 0 0 t04o6250.dat
1 16 0 17 0 -8 0 0 0 6.4 0 0 0 -8 t04o6250.dat

The gap can actually be seen in plain text here as 6.4 will give 12.8 and not 13.
Edit: 
Gap is smaller than first anticipated. Might be ok?

The "problem" comes from primitives rounding to 4dp. Let's calculate the gap at 45° from main directions.
For radius 13 cyli, the vertice is at x=z=round(sqrt(2)/2, 4) *13 = 9.1923
for scaled 8 torus, the vertice is at x=z=round(sqrt(2)*1.625/2, 4)*8 = 9.192
So the mismatch distance is 0.0003*sqrt(2)=0.00042, acceptable since that value is < 0.001


RE: 3626c gap - Gerald Lasser - 2024-03-12

The 6.4 is atually in the y-direction (vertical)

1 16 0 4 0 0 0 -8 0 -6.4 0 -8 0 0 t04o6250.dat

Horizontal in x and z direction  the outer radius is 13 (8 + 5)

That comes from 8 being the major radius with the minor being 0,6250 of the major, that works out to 8 x 0,6250 = 5

The slight gap is due to the scaling up of prims as Philo noted



Edit: The 6.4 work out to a scaled height of 4 LDU