Just scanned this thread for the size of the pieces to be welded and cannot find any mention. If this is a practice weld then make sure you are using metal of significant dimensions (old horse shoes are great) as thin metal cools VERY quickly and is hard to weld. Once you can weld the heavier pieces then you can progress to the finer work if that is your desire.
Also, let it soak in your fire for a while to make sure its hot right through. This can take a bit of fiddling so the outside does not burn before the innards are hot enough but a gentle, steady air flow will help so your fire hot but not raging.