It was high time to fix this lamp. It's my first alcohol-burning lantern to fettle with - Primus 391. Here is she, after cleaning and with pre-burned 200CP mantle already. Of course it was not always like that - this morning she looked little more miserable. As the lamp came without jet I've decided to refurbish her back to original configuration - for burning alcohol. Air-tube end (the one which hides in the collar) was partially crushed, probably to restrict air flow in alcohol config. I've repaired the tube and planned to turn brass component, similar to what Morgan is showing here: 1952 - Primus no 1321 för sprit (alcohol) However - as a quick fix, before I'm back in my factory's shop - I took old nut of proper size and shaped it by hand into matching form. I have no idea how small the opening should be so I took this guess. Turned out to be perfect. Second missing part was small mesh disc which Nils mentions in this thread: 1952 - Primus no 1321 för sprit (alcohol) I've punched it from one of these ugly, plastic funnels we get with our lamps. Mounted on pricker rod. Last missing part (I hope) was box nut which seals the whole assembly. I don't have any Primus donors laying around so I took it from Optimus spare parts. It almost fits, I needed to cut graphite sealer a bit and tape threads with Teflon tape - Optimus thread is not the same as used on this Primus. With this primitive but invisible fix I managed to seal the assembly. To save Primus original globe I run test with expendable Petromax glass. Forming new 200 CP mantle shown below. After the new mantle was pre-burned I re-assembled the lantern with original globe. The light output from this tiny lantern is exceeding all my expectations! My so-far best small lantern, Optimus 930, is falling on Place 2 now. Especially that it's rated on 300 CP. This tiny Primus 391 is brighter than Optimus 200/1200 in my collection!
Thank you very much! Fount on this Primus is on the verge of qualifying for de-plating process. Lots of nickel corrosion and places where underlying brass is shining through. But I gave it a chance and kept original plating. It’s a working lamp, not showroom piece so I’m OK that it shows her age.
Well done on the fettle, it's working very well. What year is it from? The hole in the air tube restrictor should be 3.5mm for the 391. The nut you found must be close considering how well it is working. You should put it in the gallery.
No renovation is complete without field tests. After all - these are tools, not just art pieces. Obligatory walk through the woods, to check post. Moderate wind and no rain - perfect for lantern test. Light output is outstanding! Heat production also. After tests I can say that Primus 391 feels best indoors or in shielded areas. At least my lamp. With night breeze the lantern flickered and I needed to adjust its position towards the wind, to keep the light. It is a perfect tent or boat lantern - especially due to lack of kerosene fumes on start/finish. Especially on boats, where many use alcohol stoves, this lamp would make sense. Noise level is moderate, not as noisy as Optimus 1551 but still far from Primus 981. Below is a "family shot" showing different Primus lamps side by side. I post it because I lacked such comparison when I was looking for field lanterns some time ago. Standing on the bench, from the left, are 2x Optimus 930, lighted lamp is Primus 391. To the right of it is Primus 981 and Primus 1020. Hanging behind is the mother of them all: Primus 1001. Monstrosity on far left is Optimus 1550.
Very well done on the restoration. Say, the hood on the 391 in the first picture looks almost like its never been used. What a picture-perfect clean up.
I'd say you're off to a great start there, Kuman! I see you've also got a Radius 119 laying around - those are great runners too once you get it to run perfectly (which shouldn't be a problem given your skills). My eyes are also drawn to the framed drawings in the background. What can you tell me about those?
Thank you Gentlemen! @Lighthouse yes, I agree with you, Radius119 is a great lantern. It is in fact this Radius which triggered my appreciation of the classic form of Primus lanterns. Acquired taste, I suppose. Before that I was a dedicated Optimus fanatic, with their steam-punk shaped founts. Good eye you have to spot these glass cage rests in the background. I’m fettling a few Radiuses 119 right now. These 2 below will be shelf-queens, given the good shape of vent ceramics. The other Radiuses in my shed have brass vents so these I use daily. But since this is alcohol-burning thread: - one of these Radiuses (with cooking plate) came to me equipped with alcohol jet and pricker: If I’m not mistaken they are P/N: Jet (Munstycket sprit): 119/28S Pricker (Rensnål sprit): 119/87S I intend to keep this configuration, given the success of Primus 391 operation, but I lack air-limitting tube 119/25S. Does anyone have a picture of it or some dimensions, so I could fabricate it?
With risk of derailing my own thread even further - these are plans for my wooden sailing boat: 1957 Laurinkoster, drawn by Arvid Laurin, of course. I renovate and sail her since few years. I’m lucky to live in a place where she was built and spent her entire life, Rosättra. Being able to check some doubts (during keel renovation) with her builder Janne Gustafsson was priceless. We are lucky in Sweden to have access to Swedish Maritime Museum (Sjöhistoriska) with their huge archives of drawings and plans!
@Henry Plews you are an angel! Thank you! Anyone in need for such a tube? I’ll make one for myself, can make more while standing at the machine anyway.
I'll take you up on that offer. I have a 118 where the top end of the tube is half burnt away. I'll send a PM.
