Summary

This is a painting handle capable of holding miniatures with bases of 25mm as well as 32mm in diameter but not limited to this. The handle makes it much easier to hold a miniature during painting. It has 2 different slots for bases of different diameter. There is also a slot on the bottom where you could glue in a 10x1 magnet in order to stick it to some metallic surface (can lids?).

UPDATE 10 May 2018:
Version 3.3.3 uploaded. Many improvements are made to the design. Among them are:

Caps design is changed and is now less prone to breaks
Center point of the slot for 25mm bases is shifted so now bases are held much better
Pins are added to the sides of the handle so it is easier to open
All parts are oriented correctly so no need to rotate them before printing

Old version of the handle is available here: https://www.dropbox.com/s/ifzvas87bq0xauw/Painting_Handle_V3.1.zip?dl=0

UPDATE 10 March 2018:

Added 0.2mm chamfer to the handle to prevent formation of 'elephant foot'

UPDATE 5 March 2018:

gap between Handle and Platform increased from 0.2 to 0.3 mm
chamfers added to the Cap

Print Settings

Printer Brand:

Prusa

                                            <p class="detail-setting printer"><strong>Printer: </strong>                     <div><p>i3 MK3</p></div></p>                                                                                <p class="detail-setting rafts"><strong>Rafts: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting supports"><strong>Supports: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting resolution"><strong>Resolution: </strong>                     <div><p>0.2</p></div></p>                                                                                <p class="detail-setting infill"><strong>Infill: </strong>                     <div><p>20%</p></div></p>                                                        <br>                        <p class="detail-setting notes"><strong>Notes: </strong>                    </p><div><p>Make sure the Caps are printed solid. For the handle I recommend to print with 3 or more perimeters.</p><h3>Print</h3><ul><li>2x Caps</li><li>2x Platform</li><li>1x Handle</li></ul></div>

Post-Printing

To assemble the handle you would need a rubber band and a paper clip.

Assembling steps

make a hook out of paper clip.
coil rubber band 3 or 4 times (I found 4 coils to work better but a bit harder to assemble)
seize coiled rubber band with the hook on one cap (see the image above)
assemble handle and 2 platforms and pass paperclip hook through holes in them (see below)

grab the rubber band with the hook and pull it out from the other side
use something to fix the rubber band from another side and put the second cap on

Enjoy!