Monday, July 13, 2015

Painted Calipers, Adaptor Holes Drilled

I'm away for work for a couple of nights, so this will be the last post regarding the brakes until Friday at the earliest.

I applied clear coat to the first of the calipers, complete with vinyl decal. I'm not 100% certain but very hopeful that the clear coat will help protect the vinyl from the heat extremes that apply to braking components.

The clearcoat really brings back the shine that shows up on these parts when the last wet coat of colour goes on (it loses its shine as it cures, unfortunately)

Fitted back onto the factory commodore caliper slide/bracket. I really need some black or silver brake paint to neaten these up. How it is will do for now (and probably forever, knowing how these things go!)

I worked out that 2.5" exhaust "pipe" is actually tube, and hence the perfect size for the alignment of the adaptor to factory rotor. It required a little bit of persuasion with a hammer to get the pipe perfectly round first.

Here's the view from inside the rotor, I needed to support the whole assembly on the adaptor so I could drill through.

I achieved this by putting some dies from my press underneath, and then clamping each side of the rotor down to keep tension on the whole setup so it wouldn't move.

First I drilled the retaining bolt hole, and fitted a nut and bolt to keep the whole assembly lined up for the other four holes. You may notice in the picture all the other adaptors on the cupboards have the retaining bolt hole drilled at this stage.

It's not pictured, but I used a nut that fitted inside the hole on the rotor perfectly and a smaller drill bit that fitted exactly through the center of the nut to drill a neatly centered pilot hole.

Here's the first adaptor completely drilled. I used a de-burring hand tool to neaten up the holes as it's much better at helping keep the flat surface perfectly flat than filing across the burrs would be. Because the alloy is so soft it's also possible to enlarge the holes slightly using the deburring tool to ensure the bolts can clear through perfectly.

Offering it up as a test fit.

This is what the clear looks like when layed on thick (the instructions call for two light coats and one "medium-wet" - this is the medium-wet coat)

It does cure clear as can be seen here. This is my second caliper. I'm not 100% happy with the location of my decal here from this angle but it's fine for all but a close inspection so it will be ok.

Here's the adaptor ring laid out on the new rotor and clamped ready for drilling. I used a wood drill bit for the alloy since it's so soft (for the large holes) - I think I'll probably need to invest in a good high speed steel bit before I drill the rotors. I'll drill the other adaptors first with what I've got and then try it on the rotors; that way if I kill the bit I have already done the adaptors, as I have to post two sets out.

Friday, July 10, 2015

Big Brake Progress

I received my shims back from the machinist (thanks Niflex Engineering) - so in preparation for fitting the calipers, last night I started to paint one of the two.

I'm sure you can all relate, once you've fitted and are using something, the desire to remove and re-work it becomes almost non-existent.

I used VHT Caliper Paint (Red)

Here's a shim fitted to the hub; it seats on the brake seat in the center (the hub then steps down for the wheel, so it looks like it doesn't fit - it has no play whatsoever though.

Holding a rotor in place. Note the rotor and shim need to be drilled to 4x100 to match the original brake rotor.

I'll use the drill press and a 63mm tube to center the shim to the original brake disc, then drill through the original holes as a guide. Once that's done I'll use the same setup and the shim itself to center the new rotor and drill that also.

The difference in size between the two setups is massive.

The VHT instructions call for two light coats followed by one "wet" coat. This is after the wet coat. Unfortunately because it's reasonably cold here (it's the middle of winter) the finish isn't as smooth as it might otherwise have been.

I cut out some PBR logos with a vinyl cutter and attached. I'm going to apply VHT Gloss Clear caliper paint over the painted/stickered caliper to help protect the finish and hold the vinyl in place (the adhesive may not otherwise hold up to the heat).

More once I get some tube and can start drilling!