Axle Folie: Don’t worry about it!
Multi-modal travel with your bike can be fantastic…and stressful - What if my bike gets broken‽‽
If packing your bike into a soft case feels like a game of Tetris, with your frame, wheels, and components teetering on the edge of collapse, and flying with it feels like a game of Russian Roulette, you’re not alone. Enter the Axle Folie: your secret weapon to keep your dropouts from experiencing the kind of crushing anxiety you’ve had at the baggage counter. Slip it in, bolt it up, and don’t worry about it!
Axle Folie was inspired by my experience with Post Carry Co.’s excellent Transfer Case. This solution addressed the one weakness I found in the case’s protection.
The Axle Folie mimics a rear hub, turning your vulnerable rear triangle into a solid unit. The Folie part? You can mount your derailleur within the rear triangle, keeping it from bouncing around and messing up your frame. And, there’s a mounting point to attach a tethered brake caliper block, which keeps inadvertent lever squeezes from messing up your brake settings. Do your worst, baggage handlers! Ok, maybe that’s going too far…..
Specifications
142mm x 12mm - fits standard frames that accept thru axle
Mounting point for disc brake pad retention block tether
Derailleur mount - threaded in printed plastic (Axel Folie-P) or pressed metal insert (Axle Folie-M) is standard M10-1 thread.
Suitable for printing in PLA or PETG
25g filament
Folie-M metal insert: MECCANIXITY Round Coupling Nut, M10-1 x 15mm - I have no affiliation, this is the best option I found
Folie-M recommended adhesive: cyanoacrylate (CA)
Benefits
Helps prevent frame’s rear dropouts from being compressed together or twisted while in transit
Provides stable fixed mounting point to rear derailleur within the rear triangle
Plastic thread version enables immediate use without additional parts required
Metal thread version accepts press-fit insert to enable countless uses
Chain does not need to be removed
Provides ability to attach disc brake pad retention block - maintains brake adjustment
Simple, inexpensive, leverages 3D printing’s structural strength under compression
Axle Folie is a great partner if you’re using bike cases that require derailleur and rear wheel removal, and do not enclose the rear dropouts with a rigid structure. Examples include:
Post Carry Co. Transfer Case - read about how the idea for the Axel Folie was born here
Thule RoundTrip Pro
Evoc Bike Travel Bag
B&W International Bike Case
Dakine Bike Roller Bag
Decathlon Bike Transport Cover
File Links
Build Instructions
Print vertically, derailleur mount closest to bed
Enable supports
2 walls, 15% Gyroid infill works well; I’m using a 0.4mm nozzle
25g in PLA
P-version: Carefully thread derailleur into mount the first time to ‘chase’ threads
M-version: Metal insert should not require great force to insert. Recommend use of adhesive for long-life; cyanoacrylate (CA) glue works well (aka Super Glue, Crazy Glue)
Any tether you have around that fits through the 5mm hole will work for retaining a brake block
Shrink-wrap works nicely to close tether loops
If you have a frame with 12mm dropouts wider than 142mm (148mm, 157mm), you can flip the print orientation 180 degrees and print a section of Axle Folie to the height you need to span the gap.
