This 16x2 1602A LCD bezel from Thingiverse printed and fitted pretty
well a few months ago, and I made a couple in anticipation of future
use.

But I'd now like to quickly make two small adjustments before printing
another in Cura:

1. Reduce the 'lip' from 4 to 2 mm. After much experiment I think I now
   have a way of making the rectangular hole in the project case with
   sufficient accuracy to allow such a tiny overlap; we'll see!

2. Reduce the diameters of the four tiny push-fit pillars by say 0.1 mm.
   A couple broke when I tried to push-fit, and I used hot glue. The change
   will probably need trial/error. (Unless I can improvise something. I'm
   thinking maybe a tightly folded cylinder of sandpaper?)

No SCAD file was available so I imported the STL (an excellent feature
of OpenSCAD). But is there some way to get the STL converted to SCAD
code?

I know I can Add, Difference, Translate, etc, but apparently not
directly change dimensions of the existing objects?

Terry

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

This 16x2 1602A LCD bezel from Thingiverse printed and fitted pretty
well a few months ago, and I made a couple in anticipation of future
use.

But I'd now like to quickly make two small adjustments before printing
another in Cura:

1. Reduce the 'lip' from 4 to 2 mm. After much experiment I think I now
   have a way of making the rectangular hole in the project case with
   sufficient accuracy to allow such a tiny overlap; we'll see!

2. Reduce the diameters of the four tiny push-fit pillars by say 0.1 mm.
   A couple broke when I tried to push-fit, and I used hot glue. The change
   will probably need trial/error. (Unless I can improvise something. I'm
   thinking maybe a tightly folded cylinder of sandpaper?)

No SCAD file was available so I imported the STL (an excellent feature
of OpenSCAD). But is there some way to get the STL converted to SCAD
code?

This 16x2 1602A LCD bezel from Thingiverse printed and fitted pretty
well a few months ago, and I made a couple in anticipation of future
use.

But I'd now like to quickly make two small adjustments before printing
another in Cura:

1. Reduce the 'lip' from 4 to 2 mm. After much experiment I think I now
   have a way of making the rectangular hole in the project case with
   sufficient accuracy to allow such a tiny overlap; we'll see!

2. Reduce the diameters of the four tiny push-fit pillars by say 0.1 mm.
   A couple broke when I tried to push-fit, and I used hot glue. The change
   will probably need trial/error. (Unless I can improvise something. I'm
   thinking maybe a tightly folded cylinder of sandpaper?)

No SCAD file was available so I imported the STL (an excellent feature
of OpenSCAD). But is there some way to get the STL converted to SCAD
code?

Thanks both, appreciate those fast replies.

Ok, understood. So, focusing on the first of those changes, what
I’m trying is to Difference() the import with something that will
preserve everything except say 2.0 mm of all edges. Struggling with
the ‘something’. Haven’t given up but any help would be much
welcomed.

Haven’t done any OpenSCAD for ages, so I’m very rusty. But if
that works maybe I could take the same differencing approach with
the four pillars?

Thanks Roger, glad to see I'm on the right track. I'll edit it having
seen your post, but here is what I had so far. I'm essentially trying to
work in 2D so your cubes are my squares. Wish I'd gone straight for this
'crude but intuitive' approach an hour or so ago, instead of trying to
create a 'difference of two squares' as my subtraction object.

difference()
{
translate([-24.25, 2.75, 0])
import("C:/Users/terry/Dropbox/3D
Printer/PROJECTS/1602_LCD_Bezel_3459425/files/1602_LCD_Bezel.stl"  );

#translate([0,51,0])
square ([100,60],center = true);

#translate([0,-51,0])
square ([100,60],center = true);

#translate([93,0,0])
square ([100,60],center = true);

#translate([-93,0,0])
square ([100,60],center = true);

}

I may try printing that soon, as the pillars are less important.
Arguably a dab of hot glue is preferable to a push fit.

On Mon, 17 Jul 2023 15:05:41 +0200, you wrote:

On Mon, Jul 17, 2023 at 01:51:07PM +0100, terrypingm@gmail.com wrote:

Thanks both, appreciate those fast replies.

Ok, understood. So, focusing on the first of those changes, what
I’m trying is to Difference() the import with something that will
preserve everything except say 2.0 mm of all edges. Struggling with
the ‘something’. Haven’t given up but any help would be much
welcomed.

on the sides you want to take something off just difference with a cube.

if your object is something roughly like

module theobject () { cube ([100,30,8]);}

and you want to take 2mm off the right you do

difference () {
theobject ();
translate ([100-2, -1,-1]) cube ([10,40,40]);
}

Note that the "40" for Z is "way" too big. I didn't want to
think about of the smaller one went in Y or Z position.

Haven’t done any OpenSCAD for ages, so I’m very rusty. But if
that works maybe I could take the same differencing approach with
the four pillars?

for the pillars you difference with a cylinder-with-thickness.

module cylinder_hollow (id, wt, h)
{
difference () {
cylinder (d=id+2*wt, h=h);
translate ([0,0,-1]) cylinder (d=id, h = h+2);
}
}

and you position that on the old pillar with id= new diameter, and
wt thick enough to take away all the extra material in the old one.

(Trick: If you make wt so small that you JUST take away all the
material you can verify that you're spot-on with the location. Then
increase wt a bit.).

Roger.

--
Terry

On 17 Jul 2023, at 13:20, Rogier Wolff R.E.Wolff@bitwizard.nl wrote:

?On Mon, Jul 17, 2023 at 11:56:54AM +0100, Terry wrote:

This 16x2 1602A LCD bezel from Thingiverse printed and fitted pretty
well a few months ago, and I made a couple in anticipation of future
use.

But I'd now like to quickly make two small adjustments before printing
another in Cura:

1. Reduce the 'lip' from 4 to 2 mm. After much experiment I think I now
   have a way of making the rectangular hole in the project case with
   sufficient accuracy to allow such a tiny overlap; we'll see!

2. Reduce the diameters of the four tiny push-fit pillars by say 0.1 mm.
   A couple broke when I tried to push-fit, and I used hot glue. The change
   will probably need trial/error. (Unless I can improvise something. I'm
   thinking maybe a tightly folded cylinder of sandpaper?)

No SCAD file was available so I imported the STL (an excellent feature
of OpenSCAD). But is there some way to get the STL converted to SCAD
code?

No you can't. Or actually you can, but it doesn't help you.

The STL file is nothing else than a list of points, and then a list of
triangles between those points. So say a cube would consist of 8 points
and 12 triangles (two for each face).

So that cylinder that you wanted to change in size is a whole lot of
points.

What I do in such a situation is to just reconstruct the openscad code
myzelf. I start out overlaying them with the STL and tweaking the
positions and sizes until I get them the same as in the STL.

Roger.

--
** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/ ** +31-15-2049110 **
**    Delftechpark 11 2628 XJ  Delft, The Netherlands.  KVK: 27239233    **
f equals m times a. When your f is steady, and your m is going down
your a is going up.  -- Chris Hadfield about flying up the space shuttle.

---

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

---

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

Thanks Roger, glad to see I'm on the right track. I'll edit it having
seen your post, but here is what I had so far. I'm essentially trying to
work in 2D so your cubes are my squares. Wish I'd gone straight for this
'crude but intuitive' approach an hour or so ago, instead of trying to
create a 'difference of two squares' as my subtraction object.

difference()
{
translate([-24.25, 2.75, 0])
import("C:/Users/terry/Dropbox/3D
Printer/PROJECTS/1602_LCD_Bezel_3459425/files/1602_LCD_Bezel.stl"  );

#translate([0,51,0])
square ([100,60],center = true);

#translate([0,-51,0])
square ([100,60],center = true);

#translate([93,0,0])
square ([100,60],center = true);

#translate([-93,0,0])
square ([100,60],center = true);

}

I may try printing that soon, as the pillars are less important.
Arguably a dab of hot glue is preferable to a push fit.

On Mon, 17 Jul 2023 15:05:41 +0200, you wrote:

On Mon, Jul 17, 2023 at 01:51:07PM +0100, terrypingm@gmail.com wrote:

Thanks both, appreciate those fast replies.

Ok, understood. So, focusing on the first of those changes, what
I’m trying is to Difference() the import with something that will
preserve everything except say 2.0 mm of all edges. Struggling with
the ‘something’. Haven’t given up but any help would be much
welcomed.

on the sides you want to take something off just difference with a cube.

if your object is something roughly like

module theobject () { cube ([100,30,8]);}

and you want to take 2mm off the right you do

difference () {
theobject ();
translate ([100-2, -1,-1]) cube ([10,40,40]);
}

Note that the "40" for Z is "way" too big. I didn't want to
think about of the smaller one went in Y or Z position.

Haven’t done any OpenSCAD for ages, so I’m very rusty. But if
that works maybe I could take the same differencing approach with
the four pillars?

for the pillars you difference with a cylinder-with-thickness.

module cylinder_hollow (id, wt, h)
{
difference () {
cylinder (d=id+2*wt, h=h);
translate ([0,0,-1]) cylinder (d=id, h = h+2);
}
}

and you position that on the old pillar with id= new diameter, and
wt thick enough to take away all the extra material in the old one.

(Trick: If you make wt so small that you JUST take away all the
material you can verify that you're spot-on with the location. Then
increase wt a bit.).

Roger.

--
Terry

On 17 Jul 2023, at 13:20, Rogier Wolff R.E.Wolff@bitwizard.nl wrote:

?On Mon, Jul 17, 2023 at 11:56:54AM +0100, Terry wrote:

This 16x2 1602A LCD bezel from Thingiverse printed and fitted pretty
well a few months ago, and I made a couple in anticipation of future
use.

But I'd now like to quickly make two small adjustments before printing
another in Cura:

1. Reduce the 'lip' from 4 to 2 mm. After much experiment I think I now
   have a way of making the rectangular hole in the project case with
   sufficient accuracy to allow such a tiny overlap; we'll see!

2. Reduce the diameters of the four tiny push-fit pillars by say 0.1 mm.
   A couple broke when I tried to push-fit, and I used hot glue. The change
   will probably need trial/error. (Unless I can improvise something. I'm
   thinking maybe a tightly folded cylinder of sandpaper?)

No SCAD file was available so I imported the STL (an excellent feature
of OpenSCAD). But is there some way to get the STL converted to SCAD
code?

No you can't. Or actually you can, but it doesn't help you.

The STL file is nothing else than a list of points, and then a list of
triangles between those points. So say a cube would consist of 8 points
and 12 triangles (two for each face).

So that cylinder that you wanted to change in size is a whole lot of
points.

What I do in such a situation is to just reconstruct the openscad code
myzelf. I start out overlaying them with the STL and tweaking the
positions and sizes until I get them the same as in the STL.

Roger.

--
** R.E.Wolff@BitWizard.nl ** https://www.BitWizard.nl/ ** +31-15-2049110 **
**    Delftechpark 11 2628 XJ  Delft, The Netherlands.  KVK: 27239233    **
f equals m times a. When your f is steady, and your m is going down
your a is going up.  -- Chris Hadfield about flying up the space shuttle.

---

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

---

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