On Wed, 2024-09-11 at 21:12 -0700, Revar Desmera wrote:

Thanks Revar and Jordan. I had no idea that even existed. It will do
fine for my use case; rezising STLs.

John. I an get to the video on Youtube, but not to the site where the
code is. Also, I do use offset fairly often, but I don't think I can
use it to resize STLs. But thanks for the response.

On 9/11/24 23:58, larry via Discuss wrote:

I was not aware that scale([x,y,z]) could accept the % as an argument.
The web pages for scale linked to by the cheat sheet pulldown do not
show that as an option. How does one go about using it that way?

Thanks.

Cheers, Gene Heskett, CET.

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.

• Louis D. Brandeis

Hi Gene,  I was referring to scaling in the 3d slicer.

I'm not sure if it is possible within bare openscad scaling, but if,
say, I have something 23.6 long, and I want it to be 23.8 long, then the
scale I use is 23.6*23.8/23.6

On 12/09/2024 18:33, gene heskett via Discuss wrote:

I use scale([1.0,1.0,1.0]) for untouched

and scale([1.0,1.0,.95]) for slightly shorter.  That what you need?

Harvey

On 9/12/2024 1:33 PM, gene heskett via Discuss wrote:

I think you mean simply scale = 23.8/23.6 which is the value that one would
enter into the scale[] parameter(s).

On Thu, Sep 12, 2024 at 14:41 Raymond West via Discuss <
discuss@lists.openscad.org> wrote:

On 9/12/2024 10:33 AM, gene heskett via Discuss wrote:

scale() has two variations:  scale(n), which scales the object by the
same ratio in all dimensions, and scale([x,y,z]), which scales by
separate ratios in each dimension.  (Oh, and scale([x,y]), which scales
a 2D object by two separate ratios.)

Neither form accepts a percentage, per se.  However, converting from
percentage form to ratio form is trivial:  just divide by 100.  If you
want to scale to half size, 50%, that's scale(0.5).  If you want to
scale to double size, 200%, that's scale(2).

scale() is really handy in my world.  I'm modeling train parts in
modeling scales, sometimes using prototype dimensions, and there's
always the inch->milllimeter conversion for printing.

What I've taken to doing is CAD-ing my parts in prototype dimensions.  I
put that code in a module(), and to render the part for printing I do this:

scale(25.4) {
    scale(1/87) {
        part();
    }
}

From inside to out, the 1/87 scales the prototype-dimensioned part to
HO scale, 1:87.  The outer scale() converts those inches to
millimeters.  If I wanted an N scale part, I'd replace 1/87 with 1/160,
O scale would use 1/48, etc.

I even have started a collection of generic parts, windows, doors,
siding patterns, etc. exposed to the world as web pages backed by
command-line openscad:

https://glenn.pulpitrock.net/customizable_models/

Note the two parameters at the bottom of each parameter list, they do
what I describe above.

Of note, Thingiverse provides a similar service; indeed, I could upload
my scripts there and they'd work the same way.

On 9/12/2024 3:22 PM, Jordan Brown via Discuss wrote:

On 9/12/24 15:41, Raymond West via Discuss wrote:

Oops..  Since tis is the OpenSCAD list, I assumed it was OpenSCAD's
scale([]);  And we all have known what you can make out of assume. ;o)>

Cheers, Gene Heskett, CET.

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.

• Louis D. Brandeis

On 9/12/24 15:41, Raymond West via Discuss wrote:

Prusaslicer also has that but I don't recall ever using it. I change
that var in OpenSCAD, and save the .scad file so it cascades the rest of
the way thru the production process. That's just the way my old Iowa
farm kid brain works. I can then load the src up tomorrow or 4 years
later and make another 50 of it if I need that many.

Cheers, Gene Heskett, CET.

"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.

• Louis D. Brandeis