Hi,

I have a small request. I can work well with POV-Ray and its numeric
coordinate system, but I find it difficult to work with WYSIWYG editors
and thus with other render software.

I am in need of a plastic part for my meat grinder (a part that allows
me to create my own sausages). I can easily create this part in POV-Ray,
but not in any other software. But I need it as a 3DS or even better as
a STL file format, in order to have someone 3D printing it for me.

My idea is that I would create that part in POV-Ray (it is a very simple
shape), and in the correct dimensions, and someone here hopefully would
be able to re-create that part in an other renderer.

Is that okay? Is here anyone who could do me this favor?

The shape is a combination of a ring (hollow), an hollow cone, and an
hollow cylinder. In my next posting here I am adding the source code. It
would be nice, if anyone could assist me. Thanks.

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Here are the exact measures of the item. If you can 3D print it (white
ABS plastic, otherwise silver), too, please let me know. I would use
PayPal to compensate you for your expenses (material and shipping to
Jamaica, inside a regular envelope with protective bubble foil or foam).

Item dimensions:
total length: 7 cm
total diameter: 6 cm (bottom ring)
angle of torus: 90°
upper ring surface exceeding torus: 0.3 cm (3 mm)
important - upper cylinder edge is rounded (torus)
torus total height: 1 cm
torus total height above ring: 0.6 cm (6 mm)
ring height: 0.4 cm (4 mm)


-----------------------------------------------

#version 3.7;

// All measures in centimeters, not meters!
// If you do the 3D printing, please print in white ABS plastic
(otherwise silver). Thanks.


difference // the ring - widest and bottom part of the item
{
 cylinder { < 0.0, 0.0,  0.00 > < 0.0, 0.0, 0.40 > 3.00 }  // outer
diameter: 6 cm, thickness (height): 4 mm (0.4 cm)
 cylinder { < 0.0, 0.0, -0.01 > < 0.0, 0.0, 0.41 > 2.45 }  // inner hole
diameter: 4.9 cm
 pigment { rgbf < 1.0, 1.0, 1.0, 0.8 > }
}

difference // the cone - middle part of the item
{
 cone { < 0.0, 0.0,  0.00 > 2.85, < 0.0, 0.0, 1.00 > 1.85 pigment { rgbf
< 0.0, 1.0, 0.0, 0.5 > } } // angle of the cone: 45°, wall thickness:
3.5 mm, lower outer diameter on ring bottom: 5.7 cm, upper outer
diameter: 3.7 cm
 cone { < 0.0, 0.0, -0.01 > 2.49, < 0.0, 0.0, 1.01 > 1.51 pigment { rgbf
< 1.0, 0.0, 0.0, 0.5 > } } // angle of the cone: 45°, wall thickness:
3.5 mm, lower inner diameter on ring bottom: 5.0 cm, upper inner
diameter: 3.0 cm

}

difference // the cylinder - longest and uppest part of the item
{
 cylinder { < 0.0, 0.0, 1.00 > < 0.0, 0.0, 6.85 > 1.85 }  // outer
diameter: 3.7 cm, wall thickness: 3 mm (0.3 cm)
 cylinder { < 0.0, 0.0, 1.09 > < 0.0, 0.0, 6.86 > 1.55 }  // inner hole
diameter: 3.1 cm
 pigment { rgbf < 1.0, 1.0, 1.0, 0.5 > }
}

torus
{
 1.7, 0.15
 rotate < 90.0, 0.0, 0.0 >
 translate < 0.0, 0.0, 6.85 >
 pigment { rgbf < 0.0, 0.0, 1.0, 0.5 > }
}

// --------------------------------------------------------------

camera
{
 location < 10.0, 10.0, -05.0 >
 look_at  < 0.0, 0.0, 0.0 >
 right 1.77*x
}

light_source
{
 < 1.0, 1.0, 1.0 >
 rgb < 1.98039, 1.94902, 1.89804 >
}

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Attachments:
Download 'sl - parts - meat grinder - sausage casing part.png' (34 KB)

Preview of image 'sl - parts - meat grinder - sausage casing part.png'

I took your scene and made a section view, as I couldn't figure out from 
the image or scene text exactly what the shape was. Is this correct, do 
you really need that centre membrane 0.9mm thick? Or was that a typo in 
the code?

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Attachments:
Download 'croppercapture[49].png' (54 KB)

Preview of image 'croppercapture[49].png'

> I took your scene and made a section view, as I couldn't figure out from
> the image or scene text exactly what the shape was. Is this correct, do
> you really need that centre membrane 0.9mm thick? Or was that a typo in
> the code?

And if I assume you don't want that membrane, there are a couple of 
steps/sharp points in the profile, see attached. Is that what you want? 
Depending on what 3D printer you use they might not even be resolved in 
the print.

Also see attached the STL 3D data and what the STL mesh looks like.

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Attachments:
Download 'croppercapture[50].png' (23 KB) Download 'croppercapture[51].png' (325 KB) Download 'obj1.zip' (218 KB)

Preview of image 'croppercapture[50].png'

Preview of image 'croppercapture[51].png'

Hi Scott,

and first of all - thanks a lot for answering and dedicating time to my
problem!   :-)

I don't need that sharp edge inside, that one must go.

And the sharp edge or step inside the ring bottom can go, but is not too
important.

I just did the scene with one camera angle only and thus didn't see
these sharp edges. I did it a few moments before ending my day and was
tired. Thanks for pointing out.

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And right - no "membrane" inside.

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Important is, that cylinder and cone walls have the same thickness, 3 mm
and not less (as they have to withstand a lot of pressure from the
grinded meat being forced there inside. And the cylinder walls must have
that angle of 45° and the ring must have that overhang of 33 on its top,
otherwise that part would not fit into the machine's frontal closing part.

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Am 14.01.2016 um 03:53 schrieb Sven Littkowski:

> I have a small request.

Then why the uppercase REQUEST in the subject line? ;)

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> Important is, that cylinder and cone walls have the same thickness, 3 mm
> and not less (as they have to withstand a lot of pressure from the
> grinded meat being forced there inside. And the cylinder walls must have
> that angle of 45° and the ring must have that overhang of 33 on its top,
> otherwise that part would not fit into the machine's frontal closing part.

For these sort of parts it's usually best to specify them by drawing a 
section view (like the first one I posted) and labelling the important 
dimensions. Far easier than you trying to describe what is important and 
me trying to interpret it.

Your model at the moment does not have a uniform 3 mm wall thickness, so 
if I start changing it to satisfy this requirement, I don't know what 
other dimensions are critical for you. If you want to post a cross 
section sketch (can even be hand drawn) with the dimensions marked then 
I'll make another model for you. Make sure to mark the actual dimensions 
that are important for the functionality (eg the wall thickness should 
be 3mm, angle of 45 degrees etc) rather than thinking in terms of 
coordinates that POV would require.

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Hi.

Simply to highlight, that this thread is not a common discussion thread,
but a request (and actually quite urgent).

All my other (regular) topics/threads have headlines in regular case
spelling. This here is really an important exception.

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