We now need to make the faceplate. Again I was able to purchase the 12”x 6”x1/16” brass sheet metal at Ace Hardware. I cut the metal into two 6”x 6” squares. Because the shroud is angled you will need to cut the faceplates to fit the shroud. Again I pre cut the metal and then used the disc sander to do the final metal work.
The faceplate mounted
The faceplate with 4.5inch blow hole
Once the faceplates fits and is aligned with all four sides I soldered the four corners. Next was to flip the shroud over and solder the four seams. You'll need to make sure the faceplate is flat against the sides before soldering. Next I found the center of the faceplate. Most 120mm fans have a 4 1/2” opening. Using a circle compass I drew a circle matching fan blade diameter. I then drilled a hole just inside the circle. I used an air hacksaw and cut just inside the circle. Next I used a drum sander mounted on a drill press and did the finish sanding of the circle.
Grinding the blowhole
You'll need to align the fans to each faceplate and pre-drill and tap each hole. I used 10-24 machine screws. You could also solder brass nuts to the backside of the faceplate. On my shroud I used a blind rivet nut. What this does is press a nut into the faceplate. If you decide to tap a thread you will need a 10-24 tap, and a #26 drill bit.
The fan grill
The shrouds are rather ugly looking at this point because of the heat. However, using 400 grit wet/dry sandpaper, you can really clean up the shroud. Now for the fun part, soldering the shrouds to the radiator. I position the shrouds on the heater core and very carefully solder ONLY the four corners. What looks like solder down the sides and across the top and bottom is not solder at all, but aluminum silver tape. This is used to seal the shroud. I cut the tape using a paper cutter. One cannot apply that much solder and not ruin the core!