Campagnolo AFS 140mm Rotor
Project “Rotory” Cutter
Bike Parts Pizza Cutter
Bikes and pizza make an odd but irrefutable pair. Perhaps it’s the strong Italian heritage they share; perhaps it’s the notion of sharing that’s associated with pizza, where everyone from the group – be it a group ride, or employees of a shop – get a slice. Or perhaps it’s just a sensual craving our taste buds declare after a tiring ride, but pizza is a staple of the cycling community to the point where numerous manufacturers have created bike-themed pizza cutters. So why then, is there a distinct lack of anything that elevates the user experience beyond that of a mere tool with a gimmicky twist?
Generic Bike Pizza Cutter 1
Generic Bike Pizza Cutter 2
Park Tool Pizza Cutter
Objective
I aim to create a bike-themed pizza cutter that reflects the value enthusiast cyclists place on exoticism and the premium; a pizza cutter that matches the caliber of the bikes they ride.
Chosen direction: Create a premium pizza cutter that stays true to its context by being constructed almost entirely out of bike parts.
Bike Parts List
Blade: Disc Rotor
Campagnolo AFS 140mm Rotor
Campagnolo is an Italian cycling brand with some of the richest and most influential histories in the industry. Coincidentally, they are also the only company I know of that makes a stainless steel center lock rotor that has a perfectly round perimeter.
Blade Mount: Wheel Hub
Novatec D791SB-CL 15mm Front Hub
The blade (rotor) must attach to a spinning hub, which in this case is conveniently a wheel hub. The hub will be cut in half.
Bearing: Full Ceramic
Full-SI3N4 6902 Bearing
Normal bearings will rust and are not food-safe as they use synthetic greases. However, fully ceramic bearings never corrode and require no lubrication under low loads, making them ideal for my use scenario.
Blade Position: Hub End Caps
Novatec Hub End Caps
These come as part of the hub, but their dimensions make them very useful in spacing the rotor correctly so that it is centered and doesn’t rub against the handle.
Axle: 15mm Thru-Axle
ZTTO 15mm Thru-Axle
The 15mm hub/bearing requires a 15mm axle, and a standard 15mm bike thru-axle works perfectly.
Axle Bolt: Suspension Bolt
Trek M8 Suspension Pivot Bolt
The 15mm thru-axle conveniently possesses a 7mm hollow ID, allowing me to tap in M8 threads to fix the axle to the handle. This Trek suspension pivot bolt is low-profile and elegant compared to other M8 bolts which protrude out (e.g. square-taper crank bolts)
Blade Fixing: Rotor Lockring
Shimano External Centerlock Lockring
This standard component fixes the disc rotor to the hub.
Washer: Nylon
Generic Nylon washers
Can be cut to size/modified if needed. For reducing the clamping force of the axle bolt on the ceramic bearing’s inner race (the race may crack if too much pressure is applied).
Handle Design
The only component I permitted to be a non-bike part was the handle, which I decided to make out of carbon fiber.
Carbon fiber was my material of choice as it both exemplifies the best the cycling industry has to offer, and is versatile when it comes to formal possibilities.
Stage 1: “Core” Layup
Basic CAD & Dimenioning
Wooden Offset Template
Molded using sandwich-press
0° / 90° / +45° / -45°
Saw + sandpaper for general form
Checking actual vs predicted thickness
Stage 2: Rotor Mounting
Drilling Axle Mount
17.5mm step bit
Recessed bolt head
Perfect fit
Healthy radial clearance
Test Mount
Checking Alignment
244g
Hand to scale
Ready for the next step
Stage 3: Core Aesthetic Features
Printed 1:1 Template
Step bit collection
Mini drum sanders
Spin Test
Stage 4: Rotor Sharpening
Pedal-driven sharpening
Rzor sharp
Mounted
Mounted
Final clean up
Stage 5: Flanges
Method 1: Wooden Mandrel
Failure 1: Poor compaction and uniformity of thickness
Method 2: Wrapping around a pair of positive molds
Failure 2: Workpiece moves around too much; it is imprecise.
Method 3: Cutting out 'flanges' from sheet carbon
Glued with locator pins
Success!
Correctly positioned
Cleaned off excess adhesive
Finished sanding edges
Self-spins under the tap. As long as you don’t let it crust, a soapy sponge will remove everything in seconds.
Epilogue
As an avid cyclist and bike mechanic, I set out to create something that would meet my standards of an enthusiast-grade pizza cutter for cyclists. The result was a pizza cutter that now hangs proudly on display, and enjoys frequent use whenever I feel like having pizza!
Samuel He