I would like to introduce my Petromax 835 and share the restoration process I used. First, I would like to thank @leo and @Reinhard for their valuable advice on restoring this lamp. Without their help, I would have given up. Unfortunately, I forgot to take any photos, but when I first saw this Petromax 835, I was reminded of the Rolling Stones song "Paint It Black." The entire lamp, including the brass components, was covered in a thick layer of black paint. It took me three weeks to remove all the paint, unscrew the stuck bolts, and disassemble the lamp. This was the longest period in my restoration history. The next five images show the lamp in its disassembled state. I will explain below what I did beyond the standard restoration process, which included replacing the seals, springs, pump cups and so on. No.1 : Heat-Resistant Paint As expected, most of the black enamel had deteriorated when I peeled off the paint. The exposed iron was severely rusted as well. Unfortunately, I don't have the skills to apply enamel, so I decided to remove as much of the rust as possible and then apply heat-resistant paint to prevent further rusting. In addition to using a rust remover, I physically removed the rust with a brass brush attached to an electric screwdriver. After applying the heat-resistant paint, a baking finish is required. Failure to do so will prevent the paint from adhering and will result in unpleasant odors and fumes later on. I used a simple method. First, I sprayed the items with paint. Then, I placed them on a trivet over a camping stove and baked them for about 60 minutes. No.2 : Fuel Tank One of the legs was broken, so I used hard (silver) solder to repair it and reinforced it with POR15. Fortunately, the interior of the fuel tank passed both a 24-hour pressure retention test and a cleaning test using white gasoline. Therefore, I decided not to coat the interior with POR15. (If you do coat the interior, be careful not to block the two air holes inside the cylinder on the side where the built-in pump's NRV is attached.) After removing the surface rust from the outside of the tank and reinforcing the soldered areas with POR15, I began painting. No.3 : Screw Replacement One of the defining features of Petromax models is the large number of parts they have. The Model 835 has many screws, nine of which I had to replace. This was because a previous owner had forced in the wrong size screws. The threads had deteriorated naturally, so I rethreaded them using a tap. No.4 : Nipple Replacement The Model 835 does not have a nipple cleaning function. (According to @Jörg Wekenmann, there is a model called the 835D that has this function.) However, the iron nipple has a recess around the central orifice. This makes it easy to clean the orifice from the outside with a pricker. Unfortunately, the iron nipple on my Model 835 had an enlarged orifice similar to that of an alcohol-fueled pressure lamp. If I had continued using it, it would have become fuel-rich and wouldn't have lit properly. So I replaced it with a 500CP brass nipple for the Model 829. Fortunately, the threads matched almost perfectly, and I was able to install it without any problems. No.5: Cleaning the Brass Mesh As mentioned above, the Model 835 does not have a nipple cleaning function. Therefore, it is crucial to keep the three brass filters indicated in the image clean. Depending on how often you use the lamp, it's a good idea to occasionally remove and clean the filters with a weak citric acid solution, even after restoration. No.6 : Clay Burner My Model 835 had a Model 829 clay burner attached to it with cellophane tape. Can you believe it? I think the thread size of the Model 829 clay burner is about M26 pitch 2.0. However, the thread size of my Model 835 chamber is much larger at about M29 or M28 pitch 2.0. Therefore, I couldn't fit the Model 829 clay burner without some ingenuity. Ideally, I would get a clay burner specifically designed for the Model 835, but that's nearly impossible. I considered various solutions. For example, I could hard (silver) solder the brass made 829 burner to the 835 chamber or hard (silver) solder the 829 chamber to the 835 chamber so that I could use the 829 clay burner. However, given my hard (silver) soldering skills, both solutions were a bit difficult. Ultimately, I decided to use exhaust pipe sealant to secure the 829 clay burner to the 835 chamber. I'm slightly concerned about its durability, but since clay burners for the 829 are readily available and the exhaust pipe sealant is resistant to heat but weak to physical force, I can always redo it. For the time being, I'm happy with this solution. NO.7 : Preheatcup. Almost half of the inner wall of the cup that held the preheating alcohol was missing. If it was left as is, the alcohol would leak when it boiled, which would make proper preheating impossible. I cut out a piece of aluminum, doubled it, and used it to rebuild the wall, since aluminum is easy to work with. Aluminum's melting point is around 660°C, so it is sufficiently heat-resistant. To prevent the alcohol from leaking, I secured the aluminum wall in place with exhaust pipe sealant. Next, I addressed the lighter. The brass pipe had lost its threads, so I used a thread repair die to cut a groove and secured it to the preheat cup with a nut. Finally, I screwed in a spare clay lighter that I had on hand. That concludes the main restoration process. Below, please enjoy the images of the lamp turned on. It has a badge that reads "F. RACEK & CO.," indicating that it is a Petromax 835 that was sold in India sometime between the mid-1920s and early 1940s. During that time, Franz was running an import business in Bombay, India Shinzo
@gkpllantern It's wonderful to see the care and attention to detail with which you restored the Petromax 835. My sincere respect The Petromax 835 is a gentle lamp , and it's a pleasure to listen to its soft chime on warm summer evenings.It could tell so many stories from its past.
Hello Shinzo, I'm glad I could help! It turned out to be a beautiful lamp, and now you need a second or third one... There are many other beautiful lamps in this size.
It was a satisfying read, with every single step recorded. And it was easy to understand even for a newbie like me. And the finished product is beautiful!
@Tony Press @Reinhard @leo @Tive @Camp numao @presscall @JEFF JOHNSON @ROBBO55 Thank you all for your kind comments. The hard work involved in the restoration has truly paid off. The lesson I learned from this experience is that when buying an old lamp from India, it’s essential to pay close attention to the details, as common sense may not always apply. Shinzo
The way you have presented it is very simple and the way you have presented it with pictures makes it easy to understand. I think you have restored it professionally. So can I ask you a little something? That white tube below the pre heat cup? What does it actually do? How does it work? I have never seen anything on you tube or anywhere else that does that part. Thanks kahala
@Kahala jayashan Thank you for your kind words. The small cream-colored clay lighter has a pinhole, as shown in the image. Alcohol from the preheat cup travels through a brass tube and reaches the clay lighter, where it emerges as a small flame from the pinhole. After preheating, when the shut-off valve is opened, the vaporized kerosene draws in air and reaches the mantle. At the same time, the flame from the pinhole strikes the mantle, causing it to ignite automatically. Therefore, when attaching the clay lighter to the brass tube, please make sure that the pinhole is oriented toward the mantle. Shinzo
