Llewellyn – Gear Boss
The third Design and Form by Llewellyn casting, but this time it was a small part!
Year 2005, the little fellas
31.8 and 35mm down tube gear adjuster bosses. (the little fellas)
Today it is not very often one needs to use the downtube lever braze, STI and Ergo gear/brake levers have been the norm since 1992. However, for some groupsets and some frame designs, we needed a simple gear cable adjuster boss for the down tube. There was nothing that was functional or elegant available. My desires and needs set my mind into gear. The new boss needed to use standard M5 gear cable adjusters. It needed a counter bore for the adjuster spring to sit in so when the spring is turned it does not chew paint off, thus keeping all neat and tidy. It needed to be easy to use in the frame construction process and have a good amount of shoreline to reduce possible stress risers on thin tubes.
During my previous casting projects I was finding that there was always a minor loss of interpretation from my fabricated samples and drawings to the CAD draftsman, then to the tool maker, so I felt it was time to learn how to provide my own 3D CAD drawings direct to the tool maker. It was SolidWorks CAD program and a pile of text books which was followed by many nights and weekends as I poured over the text books doing the lessons until I got the hang of it.