Had a minor setback earlier this month while installing the e-brakes. I’m sure most builders especially first timers have had some “learning” moments, so I thought I’d share mine.
Because e-brakes are an option the mounting holes aren't predrilled. Allan had a
great video on locating and drilling the holes. Unfortunately I didn’t set the punch deep enough 2nd hole and the drill bit walked on me. It was only .091” off, but I decided to redrill the hole (in hindsight thicker spacer would have worked quicker). I considered filling it with weld or brazing rod, but after talking to a machinist they suggested just making a plug. So turned & threaded a rod to M10x1.5 and added some loctite for good measure, then tried redrilling the hole. Unfortunately this didn’t work as planned and what was left of the plug wall rotated into the new hole.
After some Internet searching I ended up finding a company 15 minutes away that makes press-in threaded bushing. The bushings required a 17.5mm hole, but luckily the wonky hole I made was right in the middle of a web in the aluminum, with a good amount of material on either side. Bushing worked great and caliper bracket installed perfectly straight.
Lesson learned and the rest of the critical holes were drilled on the press.