Metal Floors (Part 1)
Regardless of the caliber of the school bus manufacturer, there’s always a bottom line that is reflected in the build quality of a school bus. Sometimes this is as simple as the ubiquitous holes in the floor from where the seats have been drilled in, and other times it can be as debilitating as poor weld seams in the metal framework of the bus. Hopefully you’ve been able to get your bus examined before you buy it, because the most important thing to look for in a prospective bus is rust!
Rust is something you won’t be able to see when you’re buying a bus from govdeals.com or any other internet website. School bus floors are usually composed of the metal base, with a layer of plywood, which is finally covered by a rubber matting of some form. This is cheap and effective for the life of the bus, though it can be a royal headache for those of us buying from school districts when they’re through with them. Some of the best tips for avoid rust are to stay away from school districts in areas where there is snow and heavy salt use on the roads, don’t buy from a church (because you know they haven’t spent any money on upkeep since they bought it), and as much as possible, look at the bottom of the bus and where the bolts come through from above. If there are any that are loose, you can bet money that water has gotten up under there and was immediately absorbed by the wood to sit for possibly decades.
I was fortunate with my school bus purchase in that it was almost entirely rust free. The basic process for working on metal floors begins with preparing the surface. An angle grinder can do light rust removal, but a metal brush extension seems to be the most popular rust-remover according to other users. A thorough sweep/vacuum of the area will remove any dust from the area that you’re going to make permanently rust-free. Trisodium Phosphate (also known as TSP) is an industrial cleaner that is extremely basic in alkalinity so that it can remove oil from metal surfaces. Mixed with water and applied using gloves and a scrubbing brush is the ideal way to scour the area clean. Once the area has dried, it’s time to apply Ospho… or since I didn’t want to spent a crap-ton of money on a brand name, I went to my local welding supply company and got a gallon of “phospho” for $25.
The “chalky” areas are where the Phospho has done it’s work. Time for Rust Reformer!
Phospho is a pretty magical liquid that is acidic and converts any iron oxide (rust) it encounters into iron phosphate, which is permanently rust-proof. Because it happens at the molecular level, I’m confident that I won’t have any more rust in those areas, but I applied a couple coats of the stuff liberally all over any area of the bus that even showed a hint of rust. I then let the phospho sit for approximately 24 hours so it could cure. Upon application to rust, the phospho would bubble, which is evidence of the chemical reaction taking place. When 24 hours had passed, I bought 6 gallons of Rustoleum’s Rust Reformer and applied three coats of the paint to the floor. Though the Rust Reformer paint claims that it also converts rust into a permanently rust-free substance, I wanted to be thorough. I’m incredibly happy with the results of Rust Reformer.
Fresh Paint on the floor… you can see the holes in the floor. My solution to those is coming in the next post!
I’m trying to prevent these posts from getting boring and overly technical, and as a result have divided it up into 2 posts. I can make an edit to add more details if there’s any desire for them. Please comment if you’re interested in more details from now on!