Hello, I am going to fettle my first lamp. So I am looking for some help and advice. I am currently putting together the list of missing or damaged parts I need to order somewhere (probably the Base Camp?). I want to clean the rest in my ultrasonic cleaner. Are there any parts that should not be cleaned this way? What bath do you recommend? Especially for brass parts? Some people fill the cleaner with pure water and put the parts in smaller jars filled with some specific bath in order to save the resources and keep the cleaner clean. One more question: Are there any risks I should be aware? It seems that there is no asbestos nor thorium mantle in my lamp. I have some experience with a propane-butane lamp and stove and once I have even successfully started a kerosene blowtorch. But I want to approach such a nice and old lamp with respect she deserves. Thanks, Franta
There are plenty of products for use with brass in an US cleaner, but whatever you do don't use ammoniated clock cleaner as it can cause cracking, particularly in items subject to stress such as founts under pressure. Just search for US brass cleaner. You could just use washing up liquid in deionised water which will clean but not brighten the brass or remove serious tarnish.
Of course. Here she is. Already quite shiny, but with several parts missing or damaged (it was sold as untested). The glass was missing. The cleaning needle is broken/missing. The nipple is clogged. The nozzle is cracked and someone glued it together probably long time ago… There is number 2862. Could you please tell me, what is modern replacement for it? The pump valve needs some service. The gaskets and packings need replacement etc. Looks like quite lot of work… and fun. I will post more photos in the gallery after some progress.
Good job so far. I would advice hytta in Germany for parts. They can tell you which parts you need and are available. So what brand did it turn into?
Nice @Franta ! Did you remove nickel plating or was it already in plain brass? Looks like mine shown here Glass is available, you can try fogas.se Globe size is 110x115. Here is example of frosted replacement (you can ”Dremel-out” Primus marking and have inspection window if you like)
It was sold as „brass“. Could you tell whether it was originally brass or nickel and chemically de-plated? I have seen your lamp before – very nice. And the lampshade makes it even better! I ordered one frosted and one clear from a different seller the day I bought the lamp. But thanks for confirmation of the size, I found out somewhere that it should be 110×115, but I was not 100 % confident. And to be honest, I am still bit unsure, what is compatible and what not. I have Optimus 300, but almost nobody sell parts explicitly for this model – they usually sell parts and accessories for Petromax 350 and 500. And e.g. Hytta says that 350 and 500 are almost same. Would the needle, nipple and nozzle be compatible?
I don’t know if Petromax and Optimus parts are compatible. I keep myself on safe side and order jets and pricker needles specificly for lamp model. Folks at Fogas seem to know their stuff. As for telling if the lamp was originally nickeled - I think we need advice of @Nils Stephenson who knows probably if there ever was Optimus 300 advertised as brass in any catalogue. After chemical de-plating there is no nickel trace anywhere, even in small bits&cranies.
Needle and nozzle are compatible but the threads on the nipple are different. You will find that a Petromax nipple will screw easily into an Optimus vapouriser but an Optimus nipple screws into a Petromax vapouriser only with difficulty.
So far, all the advertising I have seen for Optimus lamps of that era are nickel plated. Over the years it has been popular to have polished brass items (especially in the 80s) so a lot of lamps had their nickel plating removed. It is a part of the history of that particular lamp, but they didn't leave the factory that way. You also have to keep polishing the brass unless you give it a coating of some kind. Just for info, this is an Optimus 300 from the mid 1930s.
Hello again, finally I have some progress to report. I have cleaned the old parts and have ordered some spare parts (nozzle, needles, nipples, gaskets, pump leather cups…) and new clear glass and new matt glass. The new nozzle fits well and seems a good choice. I got also new nipples, but finally I was able to restore the old one (it looked hopelessly clogged before). When I installed the new pump valve, I was able to put only very small pressure into the tank (enough to do some hissing sounds but too little to make the manometer hand move). It seems that the spring in the new valve is too strong. So I rather cleaned and restored the old valve. Then I am able to get 2 bar in the tank (full of air, without any liquid). I have some questions before I pour the kerosene inside and burn the mantle… When the cleaning needle is in the upper position, the needle and nipple works like an (imperfect) closed valve. The pressure decreases from 2 bar to zero in circa 50 minutes. Is it normal or should I look for leaks? An manual says: „pump from time to time in order to maintain the desired light“ – but how often is it approximately? When the notch on the wheel is up, should the needle be also in the upper position? As I bought the lamp, it is opposite (notch up = needle down). But according to some manuals, it seems wrong (however the manual talks about the wheel arrow and is for a newer lamp). The manometer, I bought, was labeled as metric M7. The diameter is the same, but the threads are bit different and it is possible to screw it only few revolutions without damaging the threads in the tank. Then it leaks quite lot, but a teflon tape fixed that. I used this setup only to test the pump/valve. Franta
HI @Franta . The needle is only there to clear blockages in the jet. If you try to use it as a valve it will eventually get covered in carbon deposits and fail. It should be out of the way. You can work out if the arrow should be up or down by looking to see if the needle is up or down relative to the arrow. Normally arrow down, needle down. Later optimus designs did have a valve inside the tank at the bottom of the fuel pipe. Your earlier model does not. It does sound like you have a leak I would expect longer - however other factors can affect this such as how full the tank is. To light it - preheat with no pressure, then pump. To switch off - release pressure. For leak finding I would use the bucket of water trick - pump up empty lantern after removing everything to just leave the whole vapouriser and valve etc on the tank. Put in bucket. The only place air should come from is the jet. Removing the pump rod/leather will also show if you have a leak coming from the pump valve. I suspect you may be more successful using the original filler cap and not the manometer one. Keep going - you are nearly there ! Chris
Sorry forgot to say - Petromax filler caps/manometers do not fit any of my optimus lamps. If you really want a manometer get an Optimus one.
Correct, the diameter is M7 but the threads are Whitworth. That is the same as on all my Optimus (and Petromax) lamps with a fibre wheel.
Thanks for all responses. You were right, there was a leak – at the bottom edge of the tank, there was a crack. I soldered it and now it is airtight – the only place that „leaks“ is the nipple. However I was not successful for the first time. It is quite obvious and I feel bit silly about it, but maybe it helps someone: the tank must be open, because if not, the heat from soldering itself builds pressure in the tank and such air than finds its way through the hot solder before is solidifies and the leak remains even after soldering. So today I finally burned some spirit and kerosene. I started without the mantle and got some small blue flames from the jet. Then I let it cool down, put the mantle (Luxor for type 300/400) on and tried to light up my Optimus 300. It produced some light but I think that the performance was poor and there were (soft and sooty) flames around the mantle. I repeated preheating. And even after lowering the pressure, there were more (soft) flames around the jet/mantle than expected. There were also dark/brown spots on the mantle. Maybe the mixture is too rich or there is too much of it flowing from the nipple/needle point? Or is something wrong in the gas chamber? Should I try different/bigger mantle? As I recall, the excessive soft flames occurred after I used the wheel and moved the needle up and down (before and after, it was in the down position all the time)… so maybe something unstuck (while during the first test without the mantle, the blue flames looked quite small and there were no soft/sooty flames).
Hi Franta, how much pressure / how many pumps are you using ? - it looks like not enough pressure to me but difficult to tell from here.. I can also see in an earlier picture you posted that there was a pricker placed in the jet/nipple. In my experience these tend to be larger than the hole in a 300 jet. This might be an indicator of a worn jet ? Also make sure everything is done up tight - jets can loosen with use. Many here use a little metallic grease in the threads. (copper/nickel) The mantle is fine (quality and size) - the black stuff usually dissappears after correct burning for a while - or you can use a blowtorch to burn it off
The pressure was low, but when I pumped more, it was getting worse (more soft flames and unstable light) so I rather stopped. This time I continued pumping and after some break point the lamp started to produce decent and stable light and even the dark spots on the mantle disappeared. So I am happy now.
Excellent news Franta ! - I am very happy for you. Not an easy fettle for a first attempt - so congratulations on a job well done. Now onto the next one.... One question - what are you pre-heating with ? - it looks very "orange" in the earlier photo
@Franta You did an excellent job of restoring your lantern. It looks great and appears to be running very well, congratulations. As for sonic cleaning, I use a cleaning liquid concentrate that is made for cleaning fired brass bullet cases. This product, and other brands like it, can be bought from a gunsmith or gun dealers. Cheers Pete
