Hi all I find this to be an odd ball of a stove, notably the filler cap, the spirit cup, the pump rod which has an O seal and not a leather, and a pump rod tube is soldered into the tank horizontally and not the usual lip on the tank to angle the tube down towards the bottom of the tank. The top of the legs have just been rough cut, not the usual flat end. On picture 7, the right of the two is the Optimus pump piston, the other one is of the Juwel 41. Regards Ian
Hmmm has someone been playing stove doctor before you owned it. The funny thing is the smaller engraving of the number 1 above and to the right of the lager number 1. seen in picture 2.
Yes, Andrew is right, some one has had the pump tube out in the past. I love that filler cap, what beautiful knurling, (nurling ?)
Hi Ian, I believe that your Optimus No.1.1 is essentially original. It is a later madel Optimus No.1 dating from the late 1960/1970s, after the formation of the PTC in 1962. The pump-tube was installed horizontal on this particlar model and the soldering can be rather untidy. This does not affect the operation of the pump. They left the top of the stove legs with a sheared finish rather than tidying them up to squared ends, as they did on earlier stoves. In my opinion the stove markings are shallower and less impressive that on earlier Optimus stoves. I took some additional photos of my Op.1 super 1 and have posted them on CCS: https://classiccampstoves.com/threads/optimus-1-superscript-1-from-late-1960s.9879/#post-124683 Best Regards, Kerophile.
Horizontal pump-tubes can be found on some lanterns, too. Because the NRV end is above the fuel level during normal operation, if it fails, you get a gentle loss of pressure rather than a fuel leak. So it might be argued that it's a safety feature which also saves you having a mess to clear up...
I think that this stove is later than suggested here. I was still buying Optimus stoves in the 1980s, and this late model didn't appear until around 1982, shortly after which the domestic models were abandoned. You can see here how the attention to detail has been compromised: the pump, less expensive (and narrower bore) filler cap with air release built into the cap (this was a feature of less expensive models like the Primus No. 51 decades before), legs much less well made (and often bent into shape during the final assembly and rough-cut at the top), burner often off-centre, pump assembly much less well constructed (with a flimsier solder joint). The Optimus stoves from the 1960s and 1970s (including the Primus & Svea brands) were much better made. The last brochure I received from an Optimus dealer that included the venerable domestic models (1,2,3 & 5) was in 1985.
Hi, Abbahco, i believe this was one of the last Optimus No.1 models made, so I have no problem accepting the 1980s date that you propose. Best Regards, Kerophile.
I should have said also "Greetings, George". It's been a long time since I was here. Nice to get up to date on the new site, Best wishes, Peter