I decided to do this because the handlebars on Shelley's bike have a diameter of 35mm in the centre. This is a standard but uncommon size. Normally they are between 22.2mm (7/8") and 31.8mm (1.25") but a few are as large as 35mm (1 3/8"). The trouble is, that currently, there are few full size lamps that fit the largest size. The bracket on the Cycleafer lamp does not open wide enough to fit a 35mm tube.
As usual, I have used Fusion 360 to create a model and exported the parts to STL for 3D printing.
The design uses some of the components of the original clamp, including the top plate and the lever for the M4 bolt. The latest revision can reuse the original M4x30mm bolt but it does not give much room for adjustment so an M4x35mm or M4x40mm bolt is preferable.
In addition to the M4 bolt, mentioned above, for use in the latch at one end, it needs an M5x25mm socket cap bolt and nut to secure the other end.
I have printed this using PETG with slightly thicker walls than I would normally use. The walls are 1.6mm thick, to give it a little extra strength.
The first version was usable but I have made several design changes since. I have improved the fit and sloped the front so that the original M4 bolt lever will fit, just about.
I used a couple of drops of High Viscosity Superglue (CA) to hold the M5 nut in place to avoid it dropping out while trying to fit the clamp to the bike.
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Notes:
Based on the photos in the following review, I believe this clamp will also fit the 'Berlin Standard' bike lamp:
https://www.bestadvisers.co.uk/bike-headlights
Versions:
v32 First release.
v34 Closer fitting cone and a hole for a cable tie as a an alternative, should the thin tongue break.
v42 Reuse the original M4 bolt.
v46 Minor fit changes to the cone.
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Downloads:
STL models (zip file v46)
STEP model (zip file v46)
Fusion 360 archive (zip file v46)
Licence not commercial
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