Tag Archives: tunnel
After getting the old swiss cheese firewall removed from the truck I started making the new firewall for Project Pile House. I started by having one of our tech advisors Sean help me make a cardboard pattern. Once the pattern was made we scribed out the shape onto our metal using a pick from the Eastwood 4 Piece Puller/Scraper/Pick Set. I decided I wanted a smooth firewall for a "cleaned" look. Because of that I won't be running beads in the firewall so I opted for 16 gauge sheet metal.
I wanted to make clean cuts in the metal so I decided to put our Electric Metal Shears to the test and make the majority of the cuts with them. I know we only rate them to 18 gauge, but I had heard rumors that these were actually tested up to 16 gauge with no issues. I was pleasantly surprised that the shears (with well-used blades even!) cut right through the 16 gauge with no issues. I can't say how pleased I was to make those long cuts quickly with the shears. I then fired up the Versa Cut 40 Plasma Cutter to make the cuts for the radii on the tunnel notch and top outer corners. I made the cuts in a single pass with the machine on 110V at around 18 Amps and 60 PSI.
Now that I had the basic shape of the firewall cut out I did some minor trimming to make space around the headers and the valve covers for engine movement. I next made some "witness" marks in the firewall and the truck to have a quick way to match up the firewall each time I fit it. I want to make the transition into the firewall tunnel as smooth as possible so it gave me a chance to try out some new prototype tools we've been testing. We're currently working on a set of universal vice-mount T-dollies that I thought would be perfect to tip the edges of the firewall where transitions into the tunnel. The trick with these is to allow the metal to hang just over the edge of the dolly and use your body hammer to form the metal around the radius of the dolly. The result is a smooth bend in the sheet metal. Look for these to be out sometime in May or June!
By tipping and rolling the edges on the transmission tunnel transition I also added some additional rigidity to the panel that I could feel instantly after I was done hammering. I decided to test fit the panel again so I could mock up the top panel of the tunnel next. The top panel needed to have the same contour as the opening we cut in the firewall and the only good way to make that was by using an english wheel to roll the contour into a piece of sheet metal. I began by making a pattern to match the cutout in the firewall so that I could check my progress as I went. I used our new prototype Eastwood English Wheel to roll the mild curve into the panel and after a few a minutes I had a piece shaped appropriately.
I then used a couple clecos to hold the top panel in place. The fitment is pretty good and it should all blend together pretty nicely once it's welded. I still need to tackle the rest of the tunnel and begin mocking up the steering column and brake pedal before I can finally weld the firewall in place.
Just today I got some steering column parts and a frame mounted brake pedal assembly from Speedway Motors, so I should be able to steer the truck from inside the cab shortly. I've already got a nice chrome Right Stuff Detailing GM mini brake booster and master cylinder sitting on the sidelines ready to mount up once the fabrication is done so I can make Pile House stop too! Stay tuned, things are getting interesting!