Introduction: CNC Nabi Tab 20"/24" Table Stand
This table was meant to roll over a "Chill Out Chair" made for disabled people. The grooves on the table top are specially made to fit a Nabi Tab 20" & 24"
What you will need for this project is access to a CNC Machine as well as the program "Autodesk Inventor". Some more physical supplies needed are Caster Wheels (preferably with breaks to insure sturdiness), some type of wood to cut out the table with, we specifically used MDF (again to insure stability). Finally you will just need a pack of screws to screw in the supports and wheels.
- CNC Machine
- Autodesk Inventor
- Caster Wheels
Step 1: Measure Your References
Measure the depth of the wood you are using to cut out the table, since we used MDF, ours was .76".
Measure the width (hip to hip) of your Chill-out Chair. The chair we referenced was 27" wide.
Measure the length of your tablet. Ours was 20".
Measure the height of your Chill out Chair.
Step 2: Table Top
Start up Autodesk Inventor (we used the 2016 version)
Start our sketch by making the length of your Chill Out Chair.
Make your "teeth" setting the length of one "tooth" 1'' long and the "gap" in the tooth .76''. repeat this pattern until you are happy with the width of your table top. Ours was 11'' long.
Repeat the same "tooth and gap" pattern on the same side of your table. Use your first side as a blueprint for your second side, and make them look identical to each other (measurements included).
Step 3: Adding the Grooves to the Table Top
Adding the grooves is simple. Make a two rectangles where you want the grooves for the tablet and the kickstand. Since the entire tablets thickness is .9 inches, each groove should be .45 inches. Make a rectangle that is 4.5" x 24.6" for the 24 inch Tab and 4.5" x 20.9" for the 20 inch Tab. We made the first groove 1" from the endge of the table and the second groove 6" from the edge.
We also added two notches (not pictured) to on the back of the table where we are adding a support for extra strength. This is not necessary, but adds extra strength. The notches were 1" wide and went .76" (the width of our MDF) inward.
Step 4: The Legs
Be sure to account for the height of the wheels when making your legs. We subtracted the total height of the Chill Out Chair by the Caster Wheels (4.375'') by the thickness of the wood you're using (.76''). Our total height measured to be 15.365''. Repeat the same "tooth and gap" pattern with the same measurements, except this time make the "gap" first then the "tooth" so that it will be able to fit into the table-top like a puzzle.
We also added a notch on the side of the leg to create a support that would just make the table stronger. We made it similar to teeth, it is 1" tall and goes into the leg .76" (the width of our MDF).
Step 5: Putting the Table Together in Autodesk
Create an assembly in Autodesk Inventor. To do this, click create new assembly and "place" all your parts in the assembly. Then use flush constraints to fit the pieces together. Click the surface of one part then click the surface of another and Inventor will place those pieces flush together. It should only take about three constraints to get each leg correctly positioned.
Step 6: Export to Vcarve
Now that your assembly is created and hopefully all your parts fit together, right click on each surface and click export face. Export each face of the parts as DWG files. These files can then be opened in Vcarve or any other software used to create Toolpaths.
Step 7: Create Toolpaths
In Vcarve, after setting the width of your material, import all your DWGs that your created with inventor. Place them on the surface where you want them to be cut from. Next, click on each piece and from the toolpaths menu, create a toolpath for each part. To do this, set the start cut distance to 0.0", then set the cut depth to .3" past your material thickness (provided you have something for drill bit to go through). Make these outside right cuts, and set the bit to a 1/4" down cut with a speed of 18,000 rpm and a feed rate and plunge rate of 1 in/sec. Add 2 tabs and set the drill bit to make 3 passes or 1 pass for every .25". Then calculate your toolpath and save it as a Shopbot file.
Step 8: CNC
Once all your toolpaths are created and saved, load them into the shop bot software and start up the Shopbot. Calibrate your zero point and make sure the correct bit is on the machine. Check your machine completely to make sure it is running properly. Start cutting!