Optimus 48L

Discussion in 'Stove Forum' started by taku, Aug 7, 2012.

  1. taku

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    For my money, the Optimus 48 is one of the prettiest and well proportioned brass stoves made. I have been on the hunt for a boxed Optimus 48 for quite some time now - they are just not terribly common here in the US. But now, at last I have one. I would appreciate help deciding what era it was manufactured in, so am including a gallery of pictures that will hopefully provide enough clues to narrow it down.

    Here is the tin the unit arrived in - relatively good shape...

    1344304169-Optimus_48L.jpg

    Next, the frontpage of the instructions sheet. I was wondering if the numbering in the upper rh corner is significant - 90452?

    1344304259-Instructions_frontpage.jpg

    The burner assembly...

    1344306210-Burner.jpg

    Top of tank detail...

    1344304337-Top_of_tank_detail.jpg

    The photo below shows that the pump assembly has been re-soldered to the tank. You can also see a rather innovative air screw replacement, and sadly, the travel cap for the tank is not present on the end of the pump...

    1344304363-Air_vent__pump_repair.jpg

    Well, whenever you find something that has seen some use and repair, the question is will it perform as it is supposed to - in this case, the answer is, happily, yes!

    1344304389-Quietly_burning.jpg

    I could see no markings on the windscreen at all, so was wondering if it is a replacement. The burner itself seems to provide the best clue as to when it was manufactured - "Primus/Optimus" would put it after acquisition of Primus - but I would be interested in your thoughts.

    Also, what would an appropriate air screw for this stove look like?

    Many thanks for your help.

    don
     
    Last edited by a moderator: Jun 26, 2015
  2. Doc Mark

    Doc Mark Subscriber

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    Hey, Fuelish,

    Don, I think the 48 is one of the best brass stoves of it's size, no matter who made it! I love the powerful, yet great simmering burner, and I have three 48's in my collection. I'd guess your stove dates to the 1970's, and yes, I'm sure the air screw is a replacement, but as you say, nicely done. As for getting back to original, you could try Basecamp, and see if they have a proper air screw for it. Or, give A&H a shout, and see what they might have.

    The original windscreen for my own 1970's 48 is one of those folding tin ones, that folds up flat, and opens up to surround the burner, and stands on hard wire legs. I can't lay hands on it right now, but can take a photo in a week, or so, when time permits me to dig into the piles of stuff in the Hobbit Hole. Or, just check the Reference Section, in the Catalogs and Parts section, and you'll see what was offered in their catalogs during that time period. Here's the part in their 1972 catalog:

    https://classiccampstoves.com/threads/126

    These work like a champ, and really help protect the burner whilst priming, and after that, I open my windscreen just a tad, and leave it on place when cooking outdoors. Perfect! Hope that helps, and congrats on your new 48, a fine, fine stove, indeed! ;) 8) :thumbup: :clap: :clap: :D Take care, and God Bless!

    Every Good Wish,
    Doc
     
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  3. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi Don, I think this is probably a very "late" Op.48L.

    Tell us what the markings on the base of the tank say... "Made in Sweden"?

    Have a look at this thread and see how the features of your Op 48 compare:

    https://classiccampstoves.com/threads/19437

    Finally, don't be in a hurry to replace the knurled air-release screw. I believe I have seen knurled valve screws on a few late PTC Optimus/Primus stoves and have several knurled screws in my spares box.

    I will need to have a look at stove photos in the CCS Stove reference section.

    Best Regards,
    Kerophile.
     
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  4. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi Don, Have a look at the second Primus No.1 in this thread:

    https://classiccampstoves.com/threads/7282

    It is a post PTC stove and is filled with a slotted filler cap and a knurled air-screw.

    Best Regards,
    Kerophile.
     
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  5. taku

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    Thanks for your comments, gents! Before my original posting I had a look at Kerophile's reference, and noted that the filler cap is different and there is no marking on the preheater cup. Here is some additional information:

    The writing on the top of the tank states "Sole Makers of the Genuine Apparatus".

    The gasket in the filler cap says "Sweden".

    Bottom of the tank states "Made in Sweden".

    Below is a closer look at the air screw. What made me think it was a replacement was that it is two piece, with the outer knurled knob of some white colored metal soldered to the inner screw of brass. Well done, however!

    1344353656-Air_screw.jpg

    The windscreen works fine, except the burner assembly has to be removed from the tank in order to remove it. It is in two halves, but once installed cannot be removed without doing damage.

    Kerophile, you state that this is a "late PTC" model - could you clarify please? When did production of this model end? If it is a later model, it could very well be a hybrid,having bits and pieces from available parts bins.

    Don
     
    Last edited by a moderator: Jun 26, 2015
  6. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi Don, I am conscious that I am really pushing the Optimus 45/48 "dating guestimate method" here.

    I was thinking late 1970s, perhaps early 1980s as a likely date for your Op.48L.

    Following the formation of the Primus Trading Co. in 1962 a lot of miscellaneous stove parts became available and "mix and match" became the name of the game. I feel that cost cutting also became an issue and quality suffered in my opinion.

    Seeing the close up of the air-screw, and your description of its composite construction, now makes me doubt that it is an original Optimus component.

    Best Regards,
    Kerophile.
     
  7. hobowonkanobe

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    I found one of those for $20, but, it was sans burner domes, pot stands and box.
     
  8. taku

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    Yes, I would agree. Based on examples in the reference gallery and your thoughtful comments, this is likely a very late production item - late 70's early 80's sounds right.

    I will keep my eye out for an appropriate windscreen (this one will probably fit one of my other stoves) but it will do for the present. The air screw will also work until I find one that is closer to original. In any case, the stove works wonderfully and will get a field test in the coming week. Thanks all, for your comments.

    Don
     
  9. brassnipplekey

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    Discus tingly nice stove .
    One of my flavourites .
    Lovely to have , Lovely to hold But if you break it, consider it .....repairable :-) .

    Nick