Yes I've always done the 'check back half an hour later' for all welding, grinding and especially casting and in this case nothing was apparent. But it must have been smouldering undetected as it went up a good four hours later. The foundry is very well ventilated, the 'big six' fibre cement cladding having hundreds of openings where they meet the dwarf walls so the air gets changed pretty quickly (by intent) but probably disperses the smell as well.too close for comfort ,,, a cup of tea at the end of the day after hot work is no bad habbit then a look about and go home ,,,
glad it all ended as well as it did ,,,