The Marin Lives On

The exciting moment finally arrived when I got in on Wednesday evening - the last of the three packages I needed to repair my poor Marin had arrived! The problem, as I may have explained in a previous post, was that the lower front brake mount on the fork was stripped completely of its thread, causing the bolt to rattle loose and the brake to very insecurely mounted. 

The first package to arrive was the least interesting - a pair of replacement 5 mm Allen head cap screws. The second was the most interesting, as it was the Helicoil set comprising 20 of the Helicoils themselves (they look just like small springs), an M6 tap, a 6.3 mm drill bit and tools for screwing in the coil and breaking off the 'tang' (a protrusion at the bottom of the Helicoil that stretches directly across the diameter and is used to screw it into the newly cut thread). The final package was simply a tap wrench.

As it turned out, repairing the thread was a pretty simple operation: First use the drill to open up the hole to the correct diameter and clean up the inner surface a bit. Next, use the tap to (carefully) cut a new thread into the hole, obviously larger than the original thread. Then comes the insertion of the Helicoil, which just screws in. The 'spring' extends so that its coils interlock with the fresh thread and also provide another thread, of the original diameter, just by being there - fantastically simple idea I think. Then all that remains is to de-tang it as I already mentioned and put the bike back together!

Here's a video which shows a little bit of the job (don't worry, it's not 10 minutes long like the last one!)

This video was a more time-consuming project than the work on the bike! Using iMovie to chop up the raw video and GarageBand to edit the music track was tricky, and not helped by the fact that neither piece of software is by any means all that great...! The quality looks pretty rubbish, for which I apologise - if anyone is really desperate to see it in better quality feel free to let me know and I can email it or something.

music credits: Open Your Eyes by Snow Patrol