This is an old Primus silent burner that has the fixed flame ring and removable cap. But… it has holes in the bottom of the burner skirt. The holes look factory-made, rather than aftermarket — or else professionally done. I’ve not seen one with these holes before. Has anyone else? Cheers Tony
Yes; but your burner is of a later design with the removable one-piece outer burner cap, whereas the burner in question has an outer burner cap with a fixed flame ring (pictured) and separate cap (not pictured). Cheers Tony
Hi @Tony Press Have a look at this thread: Primus No.4 silent burners. The sequence of features of the No.4 silent burners, I had access to, appears to be: 1925. Fixed perforated screen, deep skirt with no punched holes at the base of the burner bowl: 1926. Removable inner and outer burner cap, deep skirt with punched holes at the base of the burner bowl. 1934. Burner design appears to be the same as above (1926 burner). 1935. Removable inner and outer burner caps, shallow skirt with punched holes at the base of the burner bowl. CAVEAT: I was using tank dating. It is of course possible that the burner could have been exchanged after manufacture. Best Regards, Kerophile.
Hi Tony: Some where I have an Optimus that has that same fixed perforated screen, with solid lid and perforated skirt, with holes punched directly through, not with the "hanging chads" of later Primus (& Optimus) burners. I'll dig it out and get back to you. Peter
interesting. thank you. it was not on a Primus stove i presume. I've not seen that combination. For clarity can you please confirm it is No.5 size? or? A side profile of yours will also confirm it is early, deep aka deep dish? The holes on yours are perplexing, i agree with the appearance of original. Re unique / developing Primus silent burner, fyi another example: An early Primus silent being for a 54 made it unique as well (re rizer). The Ben / Murph example also revealed something new for CCS, link , an early/late combination along the lines of this thread. It is: deep dish: same as early/earliest with *holes: that came later. That example has the later inner/outer caps. *the later holes on that one do have the "hanging chads" thanks again PS IF this thread is re No.5 size? another related discussion, link, among the, still, open questions: [Primus vs Optimus old deep dish silents] if anyone can tell the difference betwixt the two, pray tell ?
Hi @OMC The silent burner of a Primus /Optimus/Radius No.4 stove is physically smaller than that used on a normal No.5 type stove. The screw fit to the stove is smaller diameter, suitable for an Optimus No.00, 1 pint tank capacity stove. “ kerophile said: ↑ G'day Bruce, Here as promised are the dimensions I took of some silent burner caps; Primus No.4 stove; Inner Cap = 33.5mmOD, but lip at bottom extends to about 35mm diam. Centre hole diam.= 16.3mm, Height = 14.5mm Outer Cap = 38mm OD, but about 40mm on lower lip. Height at max, the top is domed, = 24mm. 5 Rows of holes. Primus No.5 stove; Inner Cap = 39.5mmOD, 42mmOD on bottom lip. Centre hole diam. = 16.4mm. Max Height = 16mm Outer Cap = 44.6mm OD, 47mm on bottom lip. Max. Height = 26mm. 4 Rows of holes. Primus No.6 or No.25 (# 4142) Inner Cap = 44mmOD, 45mmOD on bottom lip. Centre hole diam. = 16.4mm. Max Height = 20mm. Outer Cap = 49mmOD, 52mmOD on bottom lip. Max Ht = 26mm. 5 or 6 Rows of holes. I will have photographs somewhere if you need them, I trust this helps. Best Regards, Kerophile.
This Optimus No. 5 from c. 1915 has that same kind of burner: I'll photograph some burner details and post them. It's the only one I've seen with this burner, and it is clearly original to this stove. Peter
You asked if anyone had seen a Primus with holes. I won't bother next time. Btw it is 1926 so much later.
Sorry, @Driftwood. I wasn’t having a go at you. I was trying to clarify in the thread (after my editing time for the initial post had passed) that I was referring only to burners with a fixed ring for the outer cap. The error is in my lack of clarity in the initial post. My apologies. Best regards Tony
@OMC The burner is a No. 5 size. It came unattached to a stove, with no provenance except “pile of old stuff”. Except for the holes in the burner skirt, it looks the same as other ‘fixed outer ring’ burners I’ve found on old Primus stoves. @abbahco1 Excellent! That looks like the same setup as mine. I’ll stick mine on a stove later today and see how it performs and post some more photos. Cheers Tony
Tony: I'll post some detail pics of it soon. Have to bring it down from the attic! It has the round holes, with no overhanging "lids". It's the only one I've seen: Optimus, c. 1915. Might be worth checking a catalogue on here. If your burner was independent of a stove it may be Optimus, rather than Primus. Quite clearly the burner on my Optimus is original. Peter
@abbahco1 I’ve lined this burner up against one I have that came with a Primus cap, though not attached to a stove (see it in the background of the photo below). They look very similar, except for the holes in the burner skirt. Here are more photos, with the burner fitted with a nipple with a 0.32mm jet, a brass inner cap from a old Primus silent burner, and a Primus top cap. Cheers Tony
I think it's an Optimus burner, Tony. I've never seen a genuine Primus burner with straight holes drilled through the burner bowl, but I have an Original Optimus with that same burner. Later Optimus silent burners (from the 1950s on) also have holes drilled straight through the bowl. Peter
Thank, @abbahco1 I post it in the Reference Gallery as an early Optimus. I’ll also see if there are any small features that might distinguish Primus from Optimus (aside from the holes). Cheers Tony
