Silly, isn't it. And yet, I've experienced this feeling, this little hairs rising on the forearms, this sharp inhalation of breath, this sudden need for some type of jism deflector to avoid a soiling from a potential mild mini-orgasm, every time I get a good mix.
Mind you, I'm the one doing all the work. I could build a muller, but space is at a premium at the college. And so I mix by hand and by shovel. The recipe is simple. 100 lbs of play sand ( I'll use olivine sand if I can get it, which I can't), 6% bentonite by weight, add water to suit. The current batch had been sitting in a barrel since May. The top was dried out. The bottom still moist. A good turning and adding just a few handfuls of water got it back up to snuff.
I have a further irrational conviction that a really nice molding sand for casting metals requires some forehead sweat in it. I can provide copious amounts of that as needed. I have been told that I am the second sweatiest person on the planet. It takes mere micro-ergs of effort on my part in order for sweat to pour from me. I kind of consider that healthy.
One final act before I put the sand back into the barrel for the next casting class. I make a little sand castle. Childish? Nope. Child like!