I can relate full well to the slide rule. When it was known I would be attending Brooklyn Technical HS (a 'specialized HS', admittance by exam), my father's buddy went into Brooklyn Progress Blueprint (up the street from their office, and that was THE K & E dealer for engineering supplies and surveying instruments). He bought two K & E "Log-Log Duplex Decitrig" slide rules for me: a pocket model and a 'full length' one. Both came in leather sheaths. I was presented with these as a gift. Made more sense than the usual fountain pens given to boys entering HS in those days. I used both slide rules thru HS and engineering school. We were the last surveying class (I went to 'surveying camp' as a Civil Engineering elective in college) to do our calculations longhand, using logarithms of trig functions, interpolating to get minutes and seconds of arc, and being up most of the nights doing it. I still have those 2 slide rules in my desk here at home, along with K & E drafting instruments, a K & E planimeter, and assorted other stuff us old dinosaurs still use, tho I do use a Texas Instrument pocket calculator instead of 'logs' or slide rules. I still use an 'engineer transit' (made by Brunson) for field surveying and field layout work, and still keep my field notes in a hardbound 'field book'. I do my drawings on a ca 1900 drawing table with a "Vemco" drafting machine with Dietzgen scales on it. 'Point my leads' in a wrinkle-green finished sanding device where you crank the 'lead holder' (parlance for a draftsman's mechanical pencil) and it runs against a sanding cup (which you can't get anymore unless you find New Old Stock). I have been doing a lot of structural design calculations for high end home alterations, additions and some new builds. Covid has sent real estate prices into the stratosphere and people are buying decrepit houses and pouring 7 figure sums into them. I average two structural jobs a week for unlicensed designers or contractors, filing them as a PE. A game I play is to do the calculations mentally, or at least 'get a rough number in my head' and 'race the calculator'. Old school, where we were taught to literally use our heads rather than relying on AI.
Getting back to the original thread: got another use for swarf. Bear repellent. We have a black bear or two who know when garbage pickup will occur. These bears make the rounds of the big plastic garbage and recycling containers and wreak havoc. Bears tore the side of the plastic garbage container with their claws, and routinely will drag large bags of garbage off into the brush, or will strew garbage all over. The garbage pickup is done by a truck with hydraulic arms that grab the containers and go thru a dump cycle into the compactor body, so the driver does not leave the cab. When the bears strew the garbage, the drivers will get out of the trucks and do a cursory policing-up, but there is still some cleanup. A few weeks back, I cleaned out the chip pan on my LeBlond engine lathe. I had been machining a lot of steel, taking hogging cuts to rough some larger shafts to size and then finishing cuts and chasing threads. The chip pan was filled with oily, jagged swarf. I got a few brown-paper grocery bags and a pair of work gloves and packed the steel swarf into the grocery bags. The cutting oil was soaking thru the brown paper as I rammed the bags into the garbage container. I took the garbage & recyling containers down the driveway that evening for trash pickup early the next morning. We found the bear had left the garbage container alone, but had still gone for the recycling container (likely attracted by remnants of cat food in the tins, and remnants of food and condiments in empty cans and jars). Some cleanup and a resolve to solve the problem across the board. I sprinkled a couple of handfuls of oily swarf on top of the recycling container's contents and added a dash of diesel fuel to both containers. No more bear problem in that regard. We know the bear is around as he leaves some large 'scats' on the lawn and driveway. However, the oil swarf seems to do the trick for keeping him out of the garbage and recycling. We have to use plastic containers furnished by the 'private sanitation company', and those have no latches on them to keep the bears out, nor will the plastic stand up to our local bears' claws.
Bears have an incredible sense of smell and will eat very nearly anything including soiled infants' diapers. Apparently, the smell of cutting oil and cut steel must have over-ridden the allure of household garbage. Wife and I do like seeing the bears, and we like them as wild animals. I've wound up within about 4 feet of a black bear a couple of times, and have a healthy respect for them. They are highly intelligent and reasonably dexterous as well as incredibly strong for their size. Wife is worried that the bears might get a mouthful of steel swarf, swallow it and wind up dying in agony of lacerated innards. I tell her the bears are too smart to woof down a mouthful of steel swarf, and 'dark sulphur cutting oil' even though it contains lard oil, must not be a condiment bears like.
