Now and then, I've heard a few older machinists talk about having maintained a sort of  journal, usually during their early years in the trade, more often than not during their apprenticeship.  While sadly, apprenticeships are by and large a thing of the past, the notion of keeping a journal appeals to me as a valuable practice that one can still egage in to their benefit, even absent a formal apprenticeship. 

So, these are the pages of my metalworking journal.