Hi ,looking at the style of tank I presume it's a table lamp or heater, I have just checked all my lamps with that type of tank and they all have that same curved base plate which tells me yours is normal, if it was curved down where the base plate touched down below the sides then it would be blown, hope this helps. Regards Ian
Thanks, both. Yes table lamp but for some reason was a bit concerned as not looked at my other one for so long
They're all like that - a smooth symmetrical curve which doesn't extend down as far as the base-rim (or anywhere near it). What to look out for are when the curve of the base=plate is asymmetrical, when the lamp rocks on its base or when there's a worn patch of paint in the centre of the base. Any (or all) of those would suggest the tank has been over-pressurised - usually because someone's tried to compensate for poor light output when they should have replaced the vapouriser. It's usually only tanks from late 1956 onwards e.g. the later X246 with clip-on handle, X246A and X246B models and their contemporaries. Also note, some folk hammer the baseplate back in to stop the rocking. This is NOT a fix of the problem because the soldered base-seam is still torn and potentially dangerous.
