This is probably the worst over pressurised lantern that i have seen so far and could be yours for £40
I wonder if at sometime in the lantern’s life someone fitted a shrader valve, or something similar, to the fill cap and used compress air from a compressor. I would think it almost impossible to bulge that fount with the lantern’s inbuilt pump. Just thinking Cheers Pete
You'd be surprised at how little effort is required. Other instructions warn of the consequence of adding too much pressure "Overpumping will cause the bottom of the container to bulge . . . " Although not yet frail I'm neither beefcake nor in the flush of youth but I'm confident I could easily cause the baseplate of any X246A / X246B to bulge like the one in the image posted by @MG
Standard British engineering practice for the insurance of pressure vessels dictates a user test pressure of twice the working pressure and a manufacturers works test of twice that. So a Tilley should be OK at around 60 psi and have been works tested to 120psi. We know very well that after 1957 this is not the case and even Tilley acknowledge they won’t stand the 60psi. 100 pump strokes with 1.5 pints of fuel in the tank gets a Tilley to around 2bar or a little under 30psi. That’s proper pints of course not the short measure used in the US. Most lamps are self limiting because of the design of the pump. For instance a Vapalux pump will only generate about 60psi as a max. I know this because I have tried and even with all my weight pushing on the pump I could not exceed about 56psi. A Tilley pump might go a little higher though because the pump tube is 16mm dia and the Vapalux is 17mm so it is perhaps just possible to get to 60psi with a Tilley pump. I have in the past joked that in 1957 Tilley sacked their last engineer and employed an accountant. Not true of course but certainly from then to today in my opinion the engineering standards at Tilley are deplorable. ::Neil::
