Simple slicer question  

RE:

You do that with a Cadd /Cad (Computer aided design) software/program. Slicer is a software for slicing models after they have been designed. It has very  limited modeling capabilities, almost none in fact.  If your using a slicer software it is assumed you have a working ready to slice model for print.

If your completely new to this I might suggest spending time with a Cadd software called Blender, it's wonderful, will always! be free and has a great (really great) community behind it. Lots of info to learn for free.

Regards

Alternatively try OpenSCAD - another free download that makes this sort of thing simple for programmers.

Eg to make this:

Use this OpenSCAD script:

// Stepped cylinder example

// Edit the eight variables to taste.  There are no validity checks so use sensible values.
// For clean, no supports, printing try to keep the taper angle above 45 degrees.
// Everything is specified in millimetres.

topdiameter=100;
bottomdiameter=90;

overallheight=120;

taperstartheight=60;
taperfinishheight=70;

// to make a hollow 'cup'
ishollow=1;  // 0=no - solid, 1=yes - hollow
// the following are only used if the part is hollow
wallthick=3;
basethick=4;

$fn=100; // smoothing

if (ishollow){
    difference(){
        shape(0);
        shape(1);
    }
}  else {
       shape(0);
}

module shape(inner){
    translate([0,0,inner*basethick]){
        cylinder(d=bottomdiameter-inner*wallthick*2, h=taperstartheight-inner*basethick);
    }
    translate([0,0,taperstartheight]){
        cylinder(d1=bottomdiameter-inner*wallthick*2, d2=topdiameter-inner*wallthick*2, h=taperfinishheight-taperstartheight);
    }
    translate([0,0,taperfinishheight]){
        cylinder(d=topdiameter-inner*wallthick*2, h=overallheight-taperfinishheight);
    }
}

Copy and paste it to try it, substitute your own values and export an STL file.

Cheerio,

RE: Simple slicer question

Why is there an option to change the Z position in the slicer?  I thought I could just move one piece on top of another.  There's no way to change Z or to otherwise merge 2 pieces into 1? 

Of course you can:  Select both, right click, merge, then select only one and edit its position relative to the other.

BUT, It's horribly difficult to align accurately especially if either is an irregular or scaled shape.

Far simpler and quicker to use CAD and generate the desired shape in the first place.

Cheerio,

RE:

Posted by: @imalias

Let's say you have a cylinder and you want the bottom half to be .25 inches narrower in diameter - but still 1 piece.  How do you do that?  I can split the 2 parts and make one smaller but I want the larger one on top of the smaller one and the slicer puts the 2 pieces next to each other.  I can't seem to get them back together.  

When slicing the object, on the bottom of the slicing dialog you can change if it cuts into Objects (default) or Parts. Change the radio button to Parts and PrusaSlicer won't move any of the resultant cut parts. You can then select the bottom one and change the size as you want. Don't forget to support the new overhang as I don't know of any way to chamfer the bottom of the top part to eliminate the overhang in PrusaSlicer.

I just verified for myself that this works in PS2.9.2

RE: Simple slicer question

I'm sure you're right but maybe I'm missing some setting somewhere.  When I do this, as soon as I click Perform cut I see the whole part with no cut.  The whole piece is selected as if it's still just 1 piece.  What am I missing?

RE: Simple slicer question

https://www.tinkercad.com/   -- web based, free, and also very easy to use. Much easier to craft new things than using Slicer.

RE: Simple slicer question

Never mind - I see what I did wrong.   Thanks for the help 

RE: Simple slicer question

I'm not quite up to speed.  I did this and it worked fine - until I dropped the part on the floor.  The 2 pieces looked like they were one solid piece but came apart when they hit the floor from only 2 feet high.  How do I merge the two pieces to be just 1 piece again after making my change?

RE:

@imalias

How do I merge the two pieces to be just 1 piece again after making my change?

As you were told before, learn to use a cad software, you will be asking these questions relentlessly until you do. 

Good Luck, your going to suffer on your current path, don't expect us to suffer with you, we offered the advice.