I Lettered In Drafting…
..in both high school and college.
I stunk at both Wood Shop and Metal Working in high school, but did manage to get a industrial course that I was not only good at, but liked as well when I got to Drafting. So I kept at it, taking couple more classes in it during my time at good ol’ NBHS. After getting out of the Navy I took a Blueprint Reading in my first semester in college and realized that being a Draftsman was what I wanted to be when I grew up.
Every drawing has something called a Revision Letter that is used to keep track of any changes made to a drawing. Some places start with an A, some start with no letter before going to A, but the Valve Store(tm) starts with a – and then the first change is an A. In the beginning of my training as a draftsman I was taught that there are 5 letters that are are never used as a Rev Ltr because they might be confused as a number, I, O, Q, S & Z.
With out using those five you still get 21 revisions before you have to start over again at AA. Because ASCO has been in business for 126 years now, a few of our older drawings have the honor of dual letters. Even though there is now a prefix, those five letters are skipped again the next time around. One of the sets of drawings I was working on the other day had a B as the first letter, meaning it has had over 40 revisions. This particular drawing’s previous Rev Ltr was BH, so naturally the BI letter combo was skipped and next pair in line was used – BJ.
Now, maybe because I was in the Navy or maybe because I’m a guy or maybe I have a dirty mind, but I think there are a few 2 letter combos that don’t include the fab five that should not be used as Rev Ltrs, that’s one of them. The next one is less likely because a drawing would have to be on its 122nd revision for it to occur, but FU probably should get a pass. The next one my dirty mind comes up with is at 177and that is HJ.
Got any more?