Underburn by design? Some time ago I described my frankie version of a silent burner head for the Primus Omnilite Ti within this thread: https://classiccampstoves.com/threads/26152 In 2014 Primus announced their version of a silent burner cap for the Ti. http://www.primus.eu/omnilitetisilencer Now it's available in Europe and I was curious to see how it performs. Contrary to the pictured product the final head is different both in shape and material. It consists of mainly two parts (very thin stainless steel outer cap with a more massive inner cap) and some steel mesh inside. Besides the recommended jet with 0.36mm for cartridge gas I tried 0.35 and 0.37mm ....but it's only just a matter of time until you get a perfect underburn with this famous growling sound. With the original 0.36mm jet as recommended for cartridge gas it takes about a minute of simmering to get into underburn. With a 0.37mm jet you run into severe underburn in less than have a minute. Very impressive in some way. A 0.35 mm jet leads to just a slightly longer period of simmering before you are locked in underburn again. Note: The pictures below show the development of underburn with the smaller 0.35mm jet and Primus 4season cartridge gas. Pictures for white gas will follow. juergen
White gas performance with the recommended 0.32mm jet was acceptable, no real underburn. Running the stove with this small jet and cartridge gas leads to less power and no real underburn similar to white gas. First pic shows the 0.32 jet with cartridge gas The next pics^are white gas only Alltogether not what I had expected.... juergen
On that evidence I'd much rather have the version you constructed Juergen! I don't like the look of that underburn at all. John
I'm with you, John. I think this head will eventually make it into my collection of interesting designs juergen
try it without the wire mesh On all my experiments with a msr dragonfly and silent from a gas stove underburn was instant until I removed the mesh from the gas head.
Of course I have tried it without mesh. It's even worse. Flame lift off and extreme underburn.... I should mention that the new burner bell comes withou air inlet holes because the head sits too deep, there is no space. Air supply only commes from underneath through the five holes around the jet housing. juergen
AF thank's for good info and nice pictures! I am wondering if those mesh pieces are added later on by Primus when they have noticed that burner cap is not working properly. Maybe Primus has one or two sea containers full of non working burner caps. 8-[
I have no idea. And I have never before seen a silent head with mesh inners. But whatever they did, it doesn't work. Btw, the box says the silencer is made in EU by Primus Eesti OÜ. juergen
Have you looked inside the box for a date? Stove boxes seems have stamped date on inner surface of the box.
18. 02. 2015 Quite new There was no information sheet or something like that. Just a small bag to carry the item. That's all. juergen
ArcticFlame said It's an arrangement that works pretty well on a Tilley CS56 . I don't know about any size differential, but there's a strong resemblance between the Tilley cap and the Omnilite silencer. Maybe if the Omnilite was constructed on Tilley lines ... John
Some results of a short search for info of the Primus Silent cap. KlITyOOX5Sw[/media]]Berniedawg video Primus No 2 restoration after buried in ice 33 years German online magazine (Find the link on the right side .... "Primus OmniLite Silencer: Schalldämpfer für Benzinkocher" English translation by Google: Ken in NC
John, thanks for the Tilley link, I was not aware of this wonderful stove. I learned that the Tilley behaves similar to the Primus without mesh: Flame lift off. I could control that with reduced gas supply. But at the price of less power. At least your Tilley does not underburn. That's the difference. Ken, thr pics I have seen from Friedrichshafen 2014 are showing a different head.... juergen
Knight84, I absolutely agree with you. Primus should be able to design a working silencer which does not even come close to underburn.... If you take a look at the "magazine" Ken mentioned (it's part of the marketing of an outdoorshop in Germany....) you can see that the picture on top of the article shows a different head as well as the one on the box does. Seems as if they changed the design from a probably working one to the current version. juergen
I heard, from a good source, it is possibly recalled. Not available from Primus at this time. It really puts the making of a silent cap into perspective. Gary did a lot of trial and error to get his design down. It would seem that Primus has the resources to do that, but.... Ken in NC
Ken, yes, the Bernie caps are outstanding. I have some of the older handmade versions. In my Nova I run them on cartridge and white gas. Simmers without any of the symptons of the Primus silencer..... We will see. juergen
