New tools!  Ridgid 18", 12", and 8" pipe wrenches and a Williams USA 35mm deep impact socket.

I got some new putty to try - Evercoat Quantum1.  It is supposed to spread and sand better than the Evercoat Rage Extreme I have been using, and offer better corrosion resistance.

This week I have been working on my coolant reservoir.  This is the plastic stock piece I will be replacing.  The plan is to build approximately the same thing from aluminum, but with minor changes for a cleaner look.

Here are the purchased pieces - a threaded cap for the top, a Billet Specialties cap that matches my other reservoirs, a -6 AN fitting for the inlet, and a -10 AN fitting for the outlet.

I started by making some mounting bosses that will be welded to the car (steel) and to the reservoir (aluminum).   The steel pieces will weld through the side of the strut tower, in approximately the same spot as the original mounts.  The bolts will come in through the wheel well.

To make the steel inserts, I made a flat-bottom drill bit and turned them on the lathe.

I ordered two aluminum hemispheres from Wagner:
http://www.wagnercompanies.com/spheres_and_hemispheres.aspx

I had to drill holes in each end. I didn't want to clamp the thin-wall pieces directly in the chuck, I wanted to clamp them axially.  Here is what I came up with...

The closest piece I had to the diameter was an old brake rotor.  So I mounted it in the chuck and bored it so the spheres were a tight fit.

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Then I drilled and tapped some holes, and cut a hole in a plate.

Clamped!

hole drilled

Everything is just about ready for welding!