Here are detail photos of a well-preserved early (pre-1911, as it lacks a date code) Primus No. 5 in original condition, still sporting its original pre-reform silent burner (R 133) that was used until 1924 (I posted someplace the insert that was included by Primus to introduce customers to the "new" design, with fully removable outer hood). The early silent has no perforations cut through the burner bowl, which has the earlier straight-edged flange, not curved like the new R 138 of 1924 (later 4138, with "Primus steel" outer hood, or 4139 with brass outer hood). This particular No. 5 has the spirit cup riveted to the top of the tank, a feature that appears to have been changed by 1911 (at least my No. 5 from that year has the higher-up integral "cone" spirit cup which is of one piece with the central rising tube, located just below the burner joint, and seems to have been in use until the late teens. I have included detail close-ups as well as general shots. The delicate Primus cast-iron trivet is correct for this date and tank is unblemished, except for a discreet (and old) solder repair around the air release valve.
@abbahco1 Great stove. I have two questions: 1. Have you seen other pre-1911 Primus Nos. 5 or 1 with the "lumpy" feet? All of mine have no "foot" at the bottom of the leg. 2. Do you have an idea of the "evolution" of the trivet decorations. I have a few cast iron trivets, some without stoves; but you seem to have a good series that accompany known dated stoves. Cheers Tony
Hi Tony: The early "patent" models have the angle-cut leg bottom (which was retained for the Primus/Optimus Nos. 2 & 3 right throughout the history of paraffin models). The 1 and 5 models seem to have acquired the bulbous leg tips around 1909-10 (the likely date of this stove). (Optimus closely mirrored everything Primus did in this regard). The leg re-design, with the bulb foot appears to coincide with the familiar B.A. Hjorth stamps included on the front and right-to-front vertical panels, and the PRI-stove-MUS trademark (the older Patent models were plain). In 1930 (U) Primus altered the leg design again for the 1s and 5s (including the Jr and Sr models) to the intricate "step" shape leg, with vertical foot that was retained up to 1964, and the last AB BAHCO primus models (even though the official change-over to Optimus/Primus Trading AB is 1962). Regarding trivets: the earliest Primus trivets (for the No. 1 - pre-1900) had twice the number of connectors between the inner and outer rings, whilst the inner ring also doubled as the flame spreader for he roarer burner. The trivets pictured here seem to come from as early as 1907-8. The British agent/associate Condrup manufactured parts under license to Primus from the earliest years, including cast-iron trivets. By 1924 the pressed-steel trivets were common, though the cast iron ones were offered as alternatives. In our native Australia, many cast iron trivets were locally produced (usually unmarked) by such suppliers as Brandt's in Sydney and T.W. Sand in Melbourne. I have many of them: they are more robust than the Swedish ones, and are more likely to have survived, though many of them display the familiar cracking to the inner ring. By the time Companion (Melbourne) was licensing Svea patterns, cast-iron trivets were a thing of the past. Regards, Peter (how's our winter down there?).
@abbahco1 Thanks for that information. I will have to keep my eyes open for pre-1911 bulb-foot stoves... On the trivets, I have a few cast iron ones that show design differences in the patterns: some with "Primus", some without, but with the 0 and the diamonds on them. I should get around to posting them all in one post and see what others make of the sequence of patterns on them. I also have a couple of Brandt Bros trivets. It's been below 0C in the mornings the last week or so - a bit cooler than where you are. Cheers Tony
Hi Tony, You can identify Optimus cast-iron trivets through the sloping angle of the pot supports and the words "Made in Sweden" rough-etched on the underside. The cast iron trivet for the 1 & 5-size Primus stoves was given as R 538. By 1917 they were still picturing the earlier cast-iron trivets with multi-connectors, and also the very first pressed steel ones (the 1917 catalogue is included here on this site). P
Tony: Just saw you fettling photos of the No. 30 - great work. Looks as though someone has splayed the upper portions of the legs out a bit (those would have been vertical originally). A question: once you had removed the solder from the burner riser, how did you manage to seal the joint reliably? (as it must have leaked once, causing the overkill solder repair). Very interesting detail photos - my No. 34 and early No. 124 range have similar parts..best, Peter
@abbahco1 Peter, I think the trick is to not use too much heat so that the excess solder melts and can be wiped off, but there is still molten solder in the joint that sets rapidly. I use propane and remove the solder patiently. I've done this on a few stoves now (and have a few more in the line-up). I always pressure test them to make sure the joint is sound. Tony
Good to know. My 1924 Primus No. 5 has a less-than-beautiful solder repair in the centre that I wouldn't mind cleaning up..very nice job on the No. 30. The burner is slightly later - I wonder when it was put on? In 1921 the silent burner would still have been the early R 132 design (with the fixed perforations and the lid). It would have had a brass inner cap stamped, like the R 133, with Up/Oben/Dessus..best P
Asiatic scripts on Pre 1911 primuses is interesting could You add better quality photo of: PRI - logo - MUS and PRIMUS No 1 bottom stamping @abbahco1
Like the bulbous feet newly added to the legs those side inscriptions seem to be another feature added just before the introduction of date coding i.e. most likely 1910, as already noted above. As far as I can make out, as one would expect for that year, this also has had the word 'patent' removed from the 'Made in Sweden' tank top inscription.
Hi Gieorgi: yes, later today - I have a better camera now than when those photos were taken, so I'll haul both stoves down and create a new portfolio of systematic detail photos. Peter
graver made master die with master die - with press - was created die die - with press - creating engravings (on tank) - in top tank create process in upper process - die's was distorted repaired reconstructed thats - sometimes - could be counted on tank changes on "engravings" - could be sorted - in a few aspects
If I'm following this correctly, I think @gieorgijewski is interested in the shape/type of bottom stamping, rather than a date code?
ok... again earliest example - could be finded by me of "second multi language asiatic script" was from 1915 and for P100 was that thats mean minimal 4 years gap in existing examples where "1911" and "1912" is represented by many examples about extra photos of logo and bottom stamping - I was asking more then year ago. @Tony Press @Blackdog thats all...
