Sorry Lance, perhaps I should have explained in more detail. The redline in this instance is more of an optimum operating pressure indication as opposed to a maximum. Indeed the Petromax Lantern English operating instructions say to pump until the manometer indicates above the redline prior to operating the rapid heating device. I shouldn't have assumed everyone was familiar with this type of stove and lantern. Cheers, Graham.
Too late to edit the above. Ehhh 4B's i don't mean to critize but i'm fair sure you know the gauge is working proper so i might suggest i was out of line. Perhaps one of our mods will remove my posts. lance
Hi Lance, No problem at all - I took it as it was meant in terms of being clear safety advice and appreciate it as such. My description of "redline" whilst visually accurate (i.e. it's a "red line") was not correct in terms of the normal meaning of the phrase as regards to a pressure guage. It's not actually a red "area" above a certain pressure meaning danger. Cheers, Graham.
So, any helpful tips on how to operate a stove in such a way? My basic technique is to only heat one item per burn, then turn it off and let my stove cool a bit, open the filler cap to equalize pressure, and then re-light for the next item to be heated. My technique is rather kludgey. Any helpful tips/good rules of thumb out there? On a related note: I've been told not to use a pot that is "too large." How large is too large? Any rule of thumb here? I've been sort of eyeballing an imaginary circle whose radius is equal to the distance from the center of the stove to the end of the pot support and then figuring that my pot shouldn't go more than an inch or inch and a half (give or take) beyond that. What do you think? Is my imaginary circle idea a good rule of thumb?
I guess it's come full circle with this topic H-J. The theme I started was that once the obvious precautions have been done to replace seals in a stove, job's done provided that care is taken to use the stove sensibly. That would include keeping an eye and an ear on it to ensure it's not overheating. I've not had one do that to the point where a valve's popped, but the self-pressurising of a Svea 123 or Optimus 8R has been a bit strenuous at times! Turning down the heat checks it, by which time the food or drink is usually in need of a gentler flame too. I think that's what Arch meant when he refers to their use within bounds that ensures that the safety valve isn't activated. Cheers, John
Thank you, John. I generally listen and watch my self pressurizing stoves. Only once did one of my stoves (a Svea 123) start sounding like it was running with so much pressure that any question entered into my mind. I just, as you suggested, turned it down. Still, I'm relatively new to classic stoves, so any tips for safe operation or how to select appropriate pot sizes welcomed.
Well, "ask and ye shall be given." Check out this post from SNOWGOOSE. https://classiccampstoves.com/threads/12016 In particular, take a look at the last two paragraphs on the below included page. In particular: "According to information furnished by Optimus, gasoline stoves normally operate at an internal pressure of 7 to 10 pounds per square inch [psi]*. Their safety valves are designed to pop at 65 psi and each stove is proof pressure tested at 100 psi before a shipment. In operation, temperatures in the tank should not exceed 150 F [65.56 C]*." HJ *Items in brackets "[ ]" inserted by HJ
I know someone already made a rig to test the caps. Wonder if I could make one of my own using an empty tank to check the caps reliability. Ron
Hi Ron Bill made one with a 111 tank and a bike pump. Clever fella that Para. There is a thread about it somewhere. He took out the NRV and put a bike valve in place of the pump. Dan
