I have a Coleman nickel plated brass fount with a steel bottom. I need to remove the rust from the steel bottom (inside) Is the proper procedure to fill the fount with the electrolyte then insert a cork with a steel anode installed? (Thinking 16 penny nail) Then make the other connection to anywhere on the fount? it seems like it would work but wanted to ask. TIA, B
You can add a second anode through the fuel port. A longer rod that will almost (but doesn't) touch the baseplate would be good. Just be sure to get the polarity right and put it in a catch basin of some sort as the electrolyte will overflow the fount. I've done several this way, but have switched to evaporust and patience.
It depends on how rusty the fount is and how new your evap-o-rust is. Evap-o-rust is reuseable, I filter the used through paper coffee filter when returning it to the original container. There are several options for cleaning/derusting the inside of a fount. These are some of the methods I use and which I pick depends on the fount at hand. There are lots of other ways that folks do this that may work as well or better. I avoid using strong acids like muriatic. When I use a chemical method I try to stick to stuff that will only attack rust, not the good metal. First step is to clean and inspect the inside of the fount. If the fount has pinholes in the baseplate it's trash. I am strongly opposed to the practice of using epoxy or other products to salvage a leaking fount. Acetone seems to work to dissolve old gasoline residue. Denatured alcohol will loosen/remove the red fount coating Coleman used in the 60s-80s. If the red coating is whole, leave it. If it's flaking off then it needs to come out. Mechanical - Sometimes called the BB dance. Small metal pieces dropped into the fount and the fount shaken to mechanically remove rust. People use BBs, small nuts and bolts, screws and God knows what else. I bought 5 pounds of burnishing shot (aka jeweller's tumbling shot) 30 years ago and use that. Works better than BBs and easier to remove than screws. One pound would be enough to last a long time and you can pour out most of it then retreive the rest. I shake the fount for a while then put a running vacuum hose near the fuel port and blow compressed air through the bung. This method produces an amazing amount of dust and you want to wear a mask or respirator while doing it. Repeat the process until you see clean metal. Afterwards the inside if the fount will need washed out. I use hot water and dish washing liquid. I sometimes coat the base plate with an epoxy just to seal any residual rust/dust on the base plate. I use West System epoxy as it's fuel resistant and I have it on hand for other things. Pro - works well on lightly rusted founts or to remove big chunks if rust prior to using one of the other methods. Con - Noisy, dusty, labor intensive and not as effective, especially on heavy rust. burnishing shot Electrolysis - As discussed above, fashion sacrificial anodes from any scrap steel you have. I simply wrap the anode in painter's tap enough that it will stick in the bung hole or fuel port then hook up the power supply and let it go. The electrolyte will foam and pressurize the tank enough to overflow so put it in a plastic bucket or bin. I use old laptop power supplies or even wall warts as a power supply. The laptop one are usuall around 19v 3-4amps. I use any wall wart that is 12v and at least 1 amp. Pro - gets at all the rust, especially on steel sided founts, won't hurt good metal, turn it on and do other things while it works. Con - Can be messy Chemical - Here I'm talking about chelating agents, not acid. Evap-o-rust or the other competitors, work well I've seen different results based on using it at room temperature, heating etc. I normally use it a room temperature, although where I live that can be 90+ in the summer in my non-AC workspace. Pro - works as advertised Con - Slower than the above two methods, somewhat messy, product can be pricey. Those are methods that work for me. Not the only or even best ways, but they work.
Thank you for the comprehensive reply! It is most helpful. I have experience with using electrolysis in other applications so it was a natural choice for me. I also considered oxalic acid. I was thinking it would leave the brass alone and only attack the rust but I’m not sure. I needed to do a little more research first. The Evaporust does seem like the best option. I can always get more aggressive. Same philosophy as always modify the cheapest/easiest to replace part first lol. Maybe use BB’s first to conserve the Evsporust. Do you recommend any type of post treatment after the Evaporust? Tia, B
Anything with sharp edges/points will work better than round BBs, that's why I like burnishing shot. Knocking off the big flakes of rust before either electrolysis or evap-o-rust is a good idea. Don't waste the expensive chemicals on stuff you can knock of with a brush or other inexpensive means. After any fount cleaning process I end with hot soapy water, shaken and dumped then a couple of hot clear water rinses. I watch the rinse water to see if any particles are still coming out. I modified an old hair dryer, the kind that has a hose attached to a shower cap sort of hat so that the hose will connect to the fuel port and use that t dry the inside.
It’s alive… ☺️ There is a previous soldering job on the bung hole. It wasn’t leaking so I decided it was best to just leave it alone. Cleaned up everything, replace vaporizer, pump leather and fuel cap gasket. runs great, thanks for the guidance!!
