Introduction: CNC Rocking Stool
Fun ergonomic rocking stool to improve core strength.
The design was adapted from the open sources twistab stool http://www.twistab.org/#el-concepto
Step 1: Materials
Materials you will need:
1.Sheets of fibreboard or wood. I would recommend plywood however OSB would work fine on a budget. Do avoid MDF as it is too soft.
7.Magnet @10mm diameter
Step 2: Download Stool Drawing File
Download the attached file. These are the Rhino plans for the stool which can be sent directly to the CNC machine. Feel free to add your own touches but beware this design is perfectly balanced and any changes may alter the centre of gravity.
On the drawing you sill see little cyan rectangles around the edge of the stool drawing. These are called bridges. They are areas where the CNC will leave little pieces of uncut wood to keep the stool in place during the process. They will have to be chisel out by hand at the end.
Step 3: Find Local FabLab
CNC milling machines are fantastic but they can be a little pricey. If you don't have access to a CNC machine find your local FabLab using this website. https://www.fablabs.io/labs/map.
Step 4: Prepare CNC Milling Machine.
1.Place your wood in the CNC.
2. Screw your wood in the machine. Choose areas that won’t interfere with the design of the stool. Ask a technician for help.
Step 5: Send File to CNC Machine & Watch the Magic Happen!
Send your file to the machine and watch the magic happen. Easy!
Step 6: Remove From CNC. First Make Sure It Has Finished. Then Unscrew the Fixings and Chisel Out the Bridges Used to Keep It in Place.
First unscrew the fixings you put in during step 3. Then get a chisel and bolster and remove the bridges. Tip: keep the chisel vertical and the flat edge near the stool edge. This way you will end up with a neater edge and less to sand later.
Step 7: Piece Together the Legs
First slide the legs together. If they don't join easily they may need sanding and a gentle persuasion with a rubber hammer. Unfortunately no 2 pieces of fibreboard are exactly the same so sometimes there can be discrepancies and the joining process can be a little tight.
Step 8: Piece Together the Twist Lid.
Twist on the connecting twist lid. Again it may need sanding if you are having trouble connecting them.
Step 9: Put the Seat On.
Glue a 10mm diameter circular magnet into the hole on the underside of the seat and the top of where the lags join. Once dry place the seat on top and not only will the chair rock but will swivel as well. I know mind blown.
Step 10: Finishes.
You may want to give your stool a good sand to take away any rough edges. Or you could even stain, wax or paint it.
Step 11: Enjoy!
I would say sit back and relax but this is not the stool for that!