One of my first projects at the TechShop San Francisco was to use the ShopBot Alpha.
It started off with me wanting to make some single sheet plywood furniture, but I had no clue where to start.. After some exhaustive internet researching, I couldn't find a simple yet fun example that actually included the vector files and directions (the lazy route I was hoping for). Instead, I found some images about a fishbone chair, thanks to Upcycleus, that was originally designed by Nicolas Marzouanlian, and sells for 1100 pounds! I was able to snag some basic dimensions and get a jumpstart on the design for one on my own!
Now, you can use whatever skills/techniques at your disposal, but I chose to design/model my entire chair in SolidWorks. Then on to VCarve Pro to calculate the toolpaths to fit it all into a single sheet. Then I popped it over to the Shopbot to allow the CNC to do the cutting for me.
3/4" 4'x8' Plywood Sheet
Lots of luck
Step 1: Design and 3D Sim
With a little creativity, I figured out what had to go where and started designing my version.
I didn't want to make some mini-me scale replica, I wanted something functional that could support my weight without concern (210lbs).
DON'T FORGET!!! Measure your materials! Instead of assuming the sheet was 0.75 inches thick, I busted out the calipers.
The pine plywood I got was actually 0.720 inches in with, as opposed to the 0.703" it was advertised as. This means I made a few adjustments to the designed slots so they would fit snugly.
I busted out my trusty 3D design program and set to detailing and dimensioning the individual pieces. I'm a newb at that too, so it took me HOURS to get the splines and curves right, and then to make sure my pieces were fully defined before creating an assembly. The components I made are below,
Spine:2 of these
Big foot: For the Back
Little Foot: For the front
19 inch Rib:(basically an arc with a shallow radius of curvature and 19inch span): 2 of these
21 inch rib:(basically an arc with a shallow radius of curvature and 21inch span) 2 of these
23 inch rib:(basically an arc with a shallow radius of curvature and 23inch span) 13 of these
To check that my design might actually work without pieces butting into one another I put them all together digitally, and made some modifications to make sure that they all fit. And, Voila!
Due to some collision detection, I dropped one of the ribs and changed my slot size to 1.5 inches instead of 2.0
Step 2: Transmogrification
Now, if you don't know how to use Vcarve, well, you are in for a little learning curve. Don't fret, however, it is short and sweet! There are all sorts of programs that can do the same thing, so choose your own weapon.
Oh! One thing I would like to mention that no one else thought to tell me was that you HAVE TO LAY OUT ALL YOUR PIECES INDIVIDUALLY FIRST, and then you can use the Vcarve power to nest the individual items and add the tabs, etc
1. Be sure to close all the vectors
2. Set your material and tool dimensions correctly
3. Add the tabs (another Vcarve pro feature that is automated!)
4. Save that toolpath
Now that I have the file all laid out, like so, it is on to the Shopbot!
Step 3: Get the Wood, Slap It Down, Set the ShopBot, and Watch the Magic!
The title speaks for itself. If you've gotten this far, it's all coasting from here.
If you are serious about it, you can lacquer this baby up to a bright shine. Myself, I am probably going to just give it a linseed oil coat or two and call it a day.