Note: This isn’t a recommendation but just letting you know what I’ve done in the past.
Many people including myself have used Ronson Lighter fluid which is Naptha which is also Coleman stove fuel for cleaning and rinsing watches. It does work well but can be VERY dangerous due to it’s extremely low flash point. Absolutely no flames in the area and good ventilation is a must! Fortunately only small amounts are needed so that keeps the fumes down a little. Again its use should be approached with great CAUTION.
One advantage is that it doesn’t dissolve the shellac used to hold the roller or pallet jewels in place as does alcohol and doubles as a cleaner and rinse! Soaking the parts for a while is necessary if the parts are fairly dirty.
Other cleaners like carburetor etc. might be a bit harsh. I’ve never tried it on watches so don’t know for sure. I also know nothing about the sand you mention so I can’t comment on that.
Naptha does evaporate quickly so drying is very fast and easy. If the parts are placed under a light bulb they will dry quickly. The parts shouldn’t be allowed to get too hot as the shellac will start getting soft somewhere around 130F and will melt up around 170F. The hairspring will dry quickly if using pure Naptha. I used Naptha many times in the past for cleaning hairsprings, jewels and complete movements. Buying Coleman Camping Fuel was a cheap but effective way to go.
Again anyone deciding to go this route should be very careful about ventilation, flames and sparks.
Hope this helps!