Step 2: Fabricating fins

Before we could rivet the fins to the base plate we had to drill holes for the rivets to pass through. Each fin was drilled with a 1mm diameter bit in four places. The holes spaced about every 15mm apart, on each of the 3mm tabs.

With the first fin already soldered with a high-temp copper solder, it became the reference fin for the rest. The drilled fin was positioned immediatly adjacent to the reference fin, and the holes' location marked onto the base plate with a center punch. The fin was then removed, and the markings used as guides so that corresponding holes could be drilled into the base plate. Each hole in the 1/4" plate was drilled to a depth of approximately 3mm.

Next, 10mm lengths of 1mm diameter copper wire were cut from a spool of wire we happened to have on hand. Each of these segments was tapped with a small hammer into the holes we had just drilled. Flux, and some very small pieces of lead solder were applied to the copper wires. A torch was used to heat the whole area and solder in the joint lightly.

Step 3: Attaching fins

The solder in this first application was used to hold the copper posts in the base plate only. With the four posts firmly affixed to the base plate, the requisite fin was fed onto the wires until it was flush to the base. Then, the excess wire post was cut away and the remaining bit tapped down with a small riveting hammer to form the head of the 'rivet'.