Back in the Garage

I can't believe it's been 5 months since my last post on this blog. It's not that nothing is happening, just for some reason I haven't managed to convey work to writing. I am still contributing to the Complete Kit Car magazine Running Reports feature which I would recommend for anyone interested in understanding what it is really like to build a kit or one-off car.

For the people who tell me, or at least I hear about, who are looking at this blog to see how the car is getting on, sorry for leaving you in the dark! Let get you up to date...

There are two main sections that have had concentrated effort since I last wrote - Brakes and Wiring. Lets start with Brakes now and I'll do wiring in a few days.

For some time I have resisted putting the brakes on the car. The limited space in the garage means that with the brakes fitted there will very little room to move around the car to do other work. Unfortunately I got to a point where I could not carry on until I had the brakes fitted and knew the pipework was good and didn't need anymore work. I already had the rear suspension and drive shafts fitted so it makes sense to fit the rear brakes on the uprights, the front ones however can be attached to the pipework and bled, and left tied up to the front shock absorber mounts.

The brakes are the original Mazda MX-5 brakes. I have stripped the front ones down, sandblasted them, and panted them (roughly) the same colour as the GRP nosecone and wheel arches will be. The rear ones were not so easy as they contain an over-complicated self-adjusting mechanism for the handbrake - more on that later.

With the help of my brother (OK to be fair, he did most of it) we fitted new rubbers, seals, and pistons to the calipers. I later sprayed the rear ones orange to match the fronts. See the previous post from February for more details.

I bought a full set of brake pads and disks for the car so before putting the calipers on and filling the system with horrible brake fluid, I trial fitted the newly refurbished calipers with the pads and disks. Front - no problem. A little tight, but the hub rotated and nothing that wont free up with a little running. Rears however, not so good.

Basically, the pads and disk will not fit inside the caliper. They are about a millimeter too wide, which is miles by brake tolerances. A bit of research reveals that handbrake is to blame...

It seems the complicated self-adjusting mechanism embedded in the calipers has a tendency to self-adjust itself to a point where it cannot be adjusted back. I won't pretend to understand how this can happen and rather than spending hours, or probably months, working out what can be done about it, I have purchased some shiny new ones, and pained them orange.

Fitting them and bleeding the system was relatively easy when you have someone to help who knows what they are doing. More thanks to my brother for giving up his weekend, rewarded only with all the curry and beer he could consume (and he can consume a lot).

One problem we have was a fracture in one of the copper brake lines. Copper with work-harden, meaning it becomes more brittle as it is bent. The line that failed was the first one I fitted to the car, and it is certainly possible I worked it a lot more than it should have suffered as I tried to route it round the chassis. It was the first brake line I have ever fitted after all!

New role of copper pipe purchased and fitted.

The brakes are now in place and the system is bled and working nicely. There is a pressure sensor in the rear T-piece that will trigger the brake lights when the rest of the electrics are fitted.


Electrics next. Give me a few days...!