I bought myself what would now be called a Propelling Pencil to use when I was Drawing at Uni.
Not Artist type Drawing but straight Technical Drawings of things Open & In Line for Assembly.
I splurged on that Pencil when I redrew a drawing that couldn't be assembled and had all nasty Red Pen Marks on it when it was returned with references to Stress Points that had been introduced by the rework. The Professor being Typical of most University professors just replied that it was a Fitting Problem not a Design Problem even though there was no way that the parts which could easily be made could be assembled.
So for the rest of my Mech Engineering Course I just replied whenever asked
"That's a Fitting Problem not a Design Issue."
Got me out of needing to do so much work.
I still have that Pencil around here somewhere as it was a very nice thin one that felt great in your hand. For that matter I still have all of my drawing instruments and a very old Slide Rule which I most defiantly know where it is though by now I couldn't do any more than Multiply & Divide on it. None of the Advanced Stuff that was a mainstay of what I used to do.
Keep Up with TechRepublic