I recently acquired another old Petromax that is in decent condition but I found out the bottom of the tank is bulging quite a bit. It's bulging to the point that the tank won't sit properly. I was thinking about hammering it down but want to know of safer solutions first.
You may need to find a new fount,the fount you have has been over pressurized. and although Kerosene is safer than other fuels, the structure may be compromised.
Damn that sucks. And I thought I scored a perfectly restorable, all original Petromax made in Germany. How the hell did someone get it to overpressurize that badly?
Probably not with the pump fitted by the manufacturers. Perhaps they thought they knew better than Petromax or whoever and fitted one of those Schrader-type valves and used a compressor. That would do it...
Shoving a compressor at a lamp is an Amish trick to get more light.It works too but does have this rather unfortunate effect of blowing the tank. Ed Erb in Ohio showed me several returned Leacock tanks with blown bases and they had been given 110psi regularly. I use a compressor sometimes but always with a tyre pressure gauge so I know what I am putting in there. ::Neil::
A refrigerator compressor can be used as both an air pressure pump and vacuum pump to around 100 psi, quite useful for removing dents or bulges from fuel founts. There are several informative articles on the net about the setup and given a used compressor the largest cost is mostly for the pressure and vacuum gauges.
Hail Sam. I recently bought a Tilley R1A on Mother Ebay with a blown out fount exactly like your Petromax. When you sat it on a hard, flat surface it would wobble like a drunken sailor. I'm in the process of restoring another fount for it. I am the Ebay Sales Representative for the Amish built 'Night Hawk' lanterns that do not come equipped with a pressure gauge, a hand pump or a rapid torch, just a pre-heater cup and a Schroeder valve assembly. The point is, the manufacturer recommends no more than 40 to 50 pounds of pressure inside their stainless steel tanks. I have my oil less compressor set for 50 pounds and that seems to be just fine. Best wishes for your new Petromax. Captain Mike in Hampton, Virginia.
Hi! There are few types of lanterns (e.g. Aida and Phoebus) known to have a weak bottom of the fount, but Petromax is usually not one of them. I've fettled an old Aida 214 which had just the same problem. I found that the joint of the fount got a bit loose around the rim, in the notch where it is crimped. There were also some stress cracks in that area. So I decided to carefully hammer the notch outwards (towards the rim) so that the bottom got pulled inwards again. I used a piece of wood which would not damage the thin brass sheet. Then I fitted a brass wire of 3mm dia. inside the notch and soft soldered it. It will now hold the force and therefore prevents the bottom from coming out again when the fount gets pressurized. The solution works fine and the fount is tight around the soldered joint, but I only use low pressure on this lantern now (anyway, it's a historic piece, and it doesn't get lit so often). Best wishes, Martin
I'm near a large settlement of Amish here in Ohio and have bought a few Leacock lamps from Amish auctions that had blown out bottom fonts. I tried smashing one back in, but sadly it started to pop back out once I pressurized it using a hand pump. The Amish do tend to abuse their lamps and lantern on a regular basis, but they use these out of necessity and not from a collector standpoint. It wouldn't hurt to give it a try, but proceed with caution when you try using it. Good luck, Dan
Hi Dan What models are those leacocks and what material are they made of, the tanks of course. There is a saying that a Leacock works better and better the higher pressure - but I guess thats a truth with modification merry christmas Claus C
The Amish around here still do not use 110 volt. A few years ago many of them went to piping gas in and using ceiling lighting with gas mantels which replaced the Leacock lamps. Some used the hand pumps to pressurize the lamps others used the schrader valve to add air pressure, but not with an air compressor that goes up to 125 PSI. The normal air pressure should be 25 to 35 PSI for any lantern.
The fridge compressor used as a vacuum pump could perhaps be a means of reversing a blown tank however one would have to be very cautious as it would be easy to go too far. Then there's the problem of a reliable solder job inside an old tank.
I have knocked an old bottom-bulging Petromax fount back in so that it could stand upright again. Did that with a rubber mallet and some rags lining to prevent unwanted indentations when doing so. However, when i pumped it up using its own attached handpump close to about 3bar, the bottom bulged out again. No leaks found though. I don't see any evidence that Schrader valves were ever fitted to it and then overpumped with something other its own handpump. I suspect it has a weak bottom. I'll say it would need some further reinforcements either internally or externally. The bottom plate of the lantern is not thick or stiff enough to resist bending under that pressure.
