Hi, has anyone got a Pither stove. These things seem quite unique in operation, I can get it to light now using a blow torch! But I'm not sure on the correct use of the tool that slides into the grooves of the cheek plates and how to remove the ash without removing a lot of unburnt coal with it? There's a butterfly valve on the stove exhaust which is seized open, is this used to control the rate of burn? I would imagine that if I could close it, the stove would just emit loads of fumes? Definitely not a stove to use without a CO alarm!! Thanks for any tips on its operation.