Originally Posted by family wagon
I'm interested to know your reasoning for having hat channel made rather than using off-the-shelf tube. I've been leaning toward channel because it provides an accessible flange so I can use the same non-blind fastener (solid rivets, maybe?) up the full height of the bus.
Question for everybody generally: lap the exterior skin joints, or butt weld them so that the exterior is one giant piece? I don't think I've seen anybody go the butt weld route, but it appeals to me because my bus is so loud inside and I really want to reduce the road/wind noise. Are there any thoughts as to whether the extra effort would pay off in any meaningful way?
You nailed it. I could not find a square tube that fit perfectly, and I wanted to be able to access to the inside for paint, fasteners, wiring, and insulation.
Last reason was also the first reason. The bus was built with hat channel, I wanted to stay with hat channel bent from the same gauge of steel.
Tubing also fits into my dislikes list. Up here where I live, anything made from tubing always rusts from the inside out. Nothing like something just completely falling apart that looked fine on the exterior.
Over lap your skin seams the same as the bus builder did. Welding them would cause more buckling and beer canning.
I overlapped mine on the ribs, same as Blue Bird did.
I also overlapped my new sheets over the top of the rubrail to the bottom of the window openings. I always hated the way the water, dirt and salt would get behind the rub rail and cause a endless stream of muddy water to leak down the side of the bus.
In doing mine I learned a few things the hard way.
-If you can, make your hat channel from Galvanized steel sheet.
- Use galvanized sheet for your new steel to fill the old window openings.
- Paint your sheets black and let the sun heat them up before drilling a single hole. Keep it in the sun the entire time your bolting it on.
- Start riveting or bolting in the center of the sheet. Work your way out from there.
- Don't use to much caulk or seam seal. Less is more on the overlaps. You just need a little in a tight seam. To much will cause buckling / ripples.
- If using small 1/4 bolts, dont over tighten the sheet fasteners. This also causes ripples.
- Have the steel shop bend ribs into your new sheets that match the ribs in the bus skin down by the wheel wells. This is a big part of how the bus builders prevented the buckling / beer canning of the steel they used. It also adds looks and strength.
I will link pics tomorrow. I'm out of time.