Up north for Christmas. North here is above the artic circle. Finally came about to fettle this old HV. First time soldering with a blowtorch. Had great help reading @kerophile 's links above - thanks! Result would not have passed HV's quality control estetic-wise, but after 50+ years on a shelf, it is now a usable stove. It has seen some rough use; risertube bendt, or rather punched sideways bending the top panel. Thus the burner is off-centered by a few cm. Had to thrust the NRV open by use of a hammer. Other than that a new rubber seal and a pumpleather could only do good Come summer, I will search out dads old woodfire-kettle and serve him coffee-memories out in the garden.