[MMZ_TimeLord]

Bladerunner talks about how he gets his copper blocks all shiny and sealed on his site here.... Hope that helps...

I pressure test my blocks with air by simply fitting a length of tube to one of the barbs (4 meters is good), that has a car tyre valve in the other end. The other block barb is blocked off and about 2 bar, (24 psi), is pumped in. The block is then completely immersed in a bowl or bucket of de-aerated water and left for at least 24 hours. If there are no bubbles then there are no air leaks, and if it won’t leak air under 2 bar there is no way water or coolant will get out. Once this test was passed the block was filed clean and then finished as outlined below.

1. I use Wet and Dry, (wet), starting at about 180 grade and going down to 1200 grade with various grades in between as required. I do this with the Wet & Dry sheet on a flat surface, (glass is good), and move the block on the Wet & Dry, similar to lapping.

2. When it is smooth with the final wet & dry grade, I use T-Cut colour restorer, (designed for use on car paint that has gone dull or tarnished). Once happy all scratches are removed it's finished with car polish, (Auto Glym Silicon Resin polish), for that deep shine. Both of these are also done with a cloth flat on the glass and moving the block back and fourth.

3. Once I'm happy with the finish and it is ready to install, (won't be handled any more), I use white spirit or brake cleaner to remove any polish residue so it can be sprayed with clear cellulose lacquer to prevent the shiny metal tarnishing. This needs to built up in very thin coats initially or it will "ball", "fish eye", or "run" on shiny.