Introduction: Koosh Wheels, 74MM for Longboards
These are one of the coolest designs I've come up with. Flexible Longboard wheels! The fins allow them to compress under weight which lets them bridge cracks rather than catch in them. No more *ka-chunk*! the fins also allow for transmission of shock into the wheel reducing that ankle killing rattle. Watch the video above for more info.
Step 1: Download the STL and Material Profile
The STL file is available for download here:
Feel free to downlaod the Fusion 360 file on this page. It will allow you to tweak the dimensions more accurately than just scaling so you can get everything perfect for your printer set up. The material profile for download here is for Ninja-Tek Cheetah and works with Cura and its spin offs. This profile is set up for my specific printer (Axiom DD) but it should get you in the ballpark of a good set up for your machine.
Step 2: Open Up Cura (or a Spin Off Thereof)
1) Select file and "load model file"
2) Select Flex.stl from wherever you save your STL files
Step 3: Reorient the Part
The part needs to be rotated 90 degrees so that the flat is on the bed.
1) Select rotate from the bottom left of the preview window.
2) Click and drag the Green line until it says 90
3) (Optional) if dragging the green line wont give you exactly 90 degrees, get it as close as you can and select "Lay Flat" from the bottom left of the preview window
Step 4: Load in the Material Profile
1) Select file and then click "Open Material Profile"
2) Select the file "Ninja-Tek Cheetah.ini" from wherever you saved it after downloading it from this page
3) Open the plugins tab to confirm the numbers and sections look like the picture.
Z Height to tweak at should be set to 1
No of layers for change should be set to 1
Tweak behavior should be "tweak value and use for rest use"
New bed temp should be 100
New Extruder 1 temp should be 214
Step 5: Review Your Settings, Save the Gcode, and Set Up Your Printer for Use
Now this step changes from printer to printer so I cant really be as specific as I would like. For heated beds I recommend using wolfbite classic from Airwolf 3D for your bed prep. This stuff is great but only works on bare glass (no Katpron, buildtak, or PEI). If you aren't sure how to set your bed up for printing with flexible filaments then check the forums for your specific printer.
Important Note! The shell thickness is key here. It should be a multiple of your nozzle if you want a clean print. (eg for a .5mm nozzle set shell to 1mm, for a .4mm nozzle shell should be .8mm or 1.2mm). shell thickness will also dictate how well the wheel works. If the fins are solid at 1mm (which they are with a .5mm) then the exterior profile will be more spongy. infill can help this a bit but it will have to be DENSE to make and impact on lessening the spongyness of the exterior wheel.
Step 6: Set Up the Complete Wheels and Throw 'em on Your Board
Pictures of assembly where difficult since you need 2 hands to do this. Video gives a better representation of how it needs to be done. This video is a step by step for taking your freshly printed Koosh wheels and installing them on your board.
1) Remove your old wheel by unscrewing the nut and sliding them off the axel.
2) Press your skateboard bearings into both sides of the Koosh wheel.
3) Slide on the completed Koosh wheel
4) Screw the nut back on leaving a small amount of side to side play to allow the wheel to move freely.
5) Rinse Lather and Repeat for all wheels
6) Go try em out!
IMPORTANT NOTE! These are not as solid as what you get in the skate shop! Normal wheels have plastic cups to prevent the bearings from pulling through under high stress. Given the limitations of printing vertically a solid shelf isnt possible so I used a wedge design to keep it simple and down to 1 print. The g forces can and will pull the bearings through if you try to do super hard carves or power slides and you will almost gauranteedly fall. Go easy. These are for cruising the streets and sidewalks not tearing them up. You will still get vibrations through the board as the fins pop back straight but they are significantly dampened.