You might look into FreeCAD.  I was trying to use if for my helmet project
a few months ago.  It wasn't able to deal with the complex geometry.

Thus gene heskett hast written on Sat, Aug 13, 2022 at 12:55:31PM -0400, and, according to prophecy, it shall come to pass that:

https://raviriley.github.io/STL-to-OpenSCAD-Converter/
This is web based, therefore platform agnostic. "Editable .SCAD?" Not really, as the result of the conversion is a series of points creating the polyhedra of the model.
I don't know that one could find a program to convert an STL into readable OpenSCAD code. We'll have to wait for Artificial Intelligence to approach the concept.

On Saturday, August 13, 2022 at 01:37:59 PM EDT, Bryan Lee <leebc11@acm.org> wrote:  

You might look into FreeCAD.  I was trying to use if for my helmet project
a few months ago.  It wasn't able to deal with the complex geometry.

Thus gene heskett hast written on Sat, Aug 13, 2022 at 12:55:31PM -0400, and, according to prophecy, it shall come to pass that:

OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org

In essence, you are asking how to turn a cake into flour, sugar, eggs,
and oil.

On 8/13/2022 12:55 PM, gene heskett wrote:

The software you want is called a mesh decompiler. There are several projects that do this. The ones I know about are academic research projects and I haven't tried any of them.

Here's a research paper from June 2020 to get started:
https://dl.acm.org/doi/abs/10.1145/3385412.3386012

"Szalinski" claims to produce better OpenSCAD output than prior mesh decompilers, so maybe that's the one to start with.

This page contains instructions on how to install and run the software:
https://dl.acm.org/do/10.1145/3395645/full/

Good luck!

Doug Moen.

On Sat, Aug 13, 2022, at 12:55 PM, gene heskett wrote:

On 8/14/22 07:57, Douglas Miller wrote:

You DO have a way with words... I knew that.

But there are rules to generate that .stl. Theoretically, its should be
possible
to reverse them. Theoretically...

Cheers, Gene Heskett.

"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
  Genes Web page http://geneslinuxbox.net:6309/

Gene:

There are many ways to write OpenSCAD code that generates the same
geometry, even for something as simple as a cube.  Even if some utility
generated OpenSCAD code from an STL, the variable names would be crap,
and the comments would be absent.  You would be better off just
re-creating the object from scratch in OpenSCAD.

Jon

On 8/14/2022 12:34 PM, gene heskett wrote:

On 8/14/22 08:27, Doug Moen wrote:

Thanks Doug. That is a fairly complex install but it seems to have
worked well,
so I I bookmarked the site for instructions and will see if it is above
my pay scale.
Thank you.

Cheers, Gene Heskett.

"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
  Genes Web page http://geneslinuxbox.net:6309/

On 8/14/22 12:40, jon wrote:

I had considered that, but extracting the measurements from the device
can be fraught with errors
if using std digital calipers. I did manage to find an .stl on
thingiverse that had the uptodate
footprint I needed, so I made it, then carved away what got in the way
on an Ender 5 Plus. And
it aligned with the hot end kit I am using, so I wound up making 3
pieces, the first one fits the
back of the carriage, carries a riser to anchor the heads umbilical cord
loom, and moves the
X home switch enough to stop the bigger head from hitting frame parts.
then the .stl I found
and carved away what I didn't need, then a bar clamp that filled the
oversized holes in the
mount base and has 3mm holes to control the alignment of it all. So the
head conversion is
mechanically done. Lots more to marry the new head to marlin.

Made all of that with CF filled PETG. Strong stuff. Needs a diamond
nozzle on the printer making
them though. CF is abrasive, will eat a brass nozzle in one job.

I still have another week or two before I'll be ready to put a roll of
plastic on it. Why? It will
quadruple the size of the build envelop, and s/b faster that the $800
Prusa kit that is making
all the small stuff. None of the under $700 stuff will survive a steady
diet of PETG. It took
another $550 to make the prusa work right.

And none of this would have been possible w/o OpenSCAD. Thank you. It
has opened up
a whole new world of what I can do. See some of the pix on my web page
if interested.
The .png's came from OpenSCAD, the jpg's from my camera. Those vise
screws are made
from a plank of hard maple on a milling machine I've rebuilt from new
but BBLB junk,
and gcode I wrote. 2 of them go into my own workbench, the 3rd will go
on ebay to see
if there might be a market for more, I've got plenty of that hard maple
plank left.

I'd love it if demand made me fix/buy more printers to speed up
production. Each of those
screws is around 2 days on the mill and 10 days of printer time.
Something else to keep
me out of the bars... ;o)

Cheers, Gene Heskett.

"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
  Genes Web page http://geneslinuxbox.net:6309/

On Sat, 2022-08-13 at 12:55 -0400, gene heskett wrote:

Depending on the complexity of the .stl and how you want to modify it,
it may be possible to modify it without making it editable, or you
might be able to make it editable by writing OpenScad code to duplicate
the .stl, using the '#' character in front of your statements and
fiddling with the position and dimensions of the object.

What STL are you tryng to modify?