Can someone tell me how to make a scent/scrape dripper?
Take any small animal water bottle with the feeder tube/bead stop on the end.
Remove the bead from the metal feeder end, and take some clear plastic tubing that'll fit over the feeder's end. Make a loop in the tubing, roughly 6" in diameter.
Fill with the fluid of your choice, and squeeze the bottle to make the liquid pass around the loop and drip out. Now when the temps drop down (night time) it won't drip, but as the temps warm up (daytime) the pressure inside the bottle will force out liquid slowly. You don't need a lot of temperature difference to make it work, maybe 10deg or so.
Good luck!