I’ll admit that Halloween crafting has never been much of a thing for me, but I can appreciate a good pumpkin carving when I see one. Recently, however, I came across John Saunders video of an attempt to carve a pumpkin and I got inspired.
This week I enlisted our mechanical engineer, Matt Lennox for a challenge: mill our Bantam Tools rooster logo into the side of a pumpkin using the Bantam Tools Desktop PCB Milling Machine. Expecting pretty much total failure and a lot of pumpkin carnage cleanup, we were blown away when this actually worked!
We also learned a thing or two about workholding organic, odd-shaped materials, and Matt even showed me a few Fusion 360 tricks to go from a simple photo to an accurate model in minutes (more below if you’re interested).
Warning: Don’t attempt this on your own mill unless you can plan on a fair bit of clean up work!
Image Calibration With Fusion 360
To save on time, and quickly get a working model that we could generate toolpaths for, Matt used this neat trick in Fusion 360.
- Snap a photo.
- Measure a feature of the object.
- Insert a new canvas using the photo.
- Calibrate the canvas with the measurement you took.
- Create a sketch using the fit point spline tool.
- Using the revolve tool and the profile created in step 5, revolve 360°.
Using Sculpting Clay For Workholding
Holding something like a pumpkin — especially when there’s no room for a vice or larger fixturing on the bed — is tricky. But, when there aren’t a lot of forces at play, a simple sculpting clay like this classic Sculpey was more than sufficient for us.
Setup Sheet for the Pumpkin
In case you're curious, we've shared our setup sheet for the pumpkin.
Have you experimented with milling any unusual materials? Let us know by dropping us a line at firstname.lastname@example.org.