This model is obsolete by my Playing Card Shuffler v3
https://www.printables.com/cs/model/427943-playing-card-shuffler-v3
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Terraforming Mars board game has a lot of cards to shuffle. I've printed one card shuffler from thingiverse (https://www.thingiverse.com/thing:4825886) but it did not work well (tricky to find proper o-rings), so I have decided to create my own.
I wanted card shuffler that is customizable - hence I've created it in OpenScad (you also need https://github.com/revarbat/BOSL2/ library).
.gcode and .stl files are generated for card height 91mm and width up to 71mm. I made it larger than needed (Mars cards are 63x88mm).
To print, support is needed for shafts and handle - I recommend to use paint-on supports smart-fill functionality from PrusaSlicer.
To increase traction, I use 3 o-rings per shaft. O-rings used are 2mm thick, outer diameter 18mm, diameter size 12mm. There are 2 version of shafts - for squared and rounded o-rings. I have squared o-rings for which I use shaft with bumps (bump is 13mm diameter). For rounded o-rings, the shaft (shaft_round_oring.stl) is 13.5mm in diameter with grooves 13mm. Places for o-rings are always +1mm in diameter to o-ring not slipping.
To address various card heights, card blocker uses 45 degree slope at the bottom (see photo) so cards are not fully blocked but can slide underneath. That's why the card blocker must be printed on this slope side to the side be perfectly flat. Also the card blocker is not fixed to the card shuffler body so one can increase the hole as needed (the top part is thicker to stay fixed enough in place).
To address two cards from different sides blocking each other in the middle, card deck on one side is lower then on the other side.
The only parts I had to glue/iron (I use soldering station with flat head) are handle and big gear to their shaft. Other gears and shafts sticks fine without glue but make sure shafts turn easily (that is gears are not put too close to the body. The body parts are just stuck together - I only had to smooth the bolts a little to be able to insert them into holes.
Card shuffler in action:
EDIT 18. 1. 2022: I made a mistake in card.shuffler2 - the handle was lower than everything else. It's fixed now.
EDIT 21. 1. 2022: Added rounded shafts (shaft_round_oring.stl).
EDIT 30. 1. 2022: Uploaded version 2:
EDIT 19. 2. 2022: Added rounded shafts for v2 (shaft_round_oring.v2.stl).
The author marked this model as their own original creation.