What’s a good runoff layout for after the finish line?
I've gotten a lot of work done on my new track but I can't figure out a good enough runoff, I don't really have space for an extra turn so my original idea was to make a sort of sand put. Just got done testing it and it make the cars way slower. I don't really know how else to have them slow down without them getting launched back into the track
Discussion
The best stop boxes I've seen will isolate each lane with tall sidewalls or individual chambers so the cars don't come together. They will also have a drop off into lots of padding on the backstop and sides, so no bounce-backs on the track. On open track finishes where collisions are more likely, a simple drop off into a padded bag can help minimize any potential damage.
I saw this contraption on Etsy. I have no experience with it but it looks promising for lower speed finishes. https://www.etsy.com/listing/1701677129/race-track-guardian-hot-wheels-track?ref=hp_rv-5&frs=1&logging_key=dfaaa015f9af0d4742c47d208ecf2710b079ad2a%3A1701677129
Here are a couple photos of the stop lanes I use on the Buckeye Mountain Raceway. It's basically three enclosed woooden lanes that are slightly wider than the track lane width. I screwed cheap PVC baseboard moulding onto the sides of the wooden lanes for the side rails. The bottom and sides are lined with self adhesive velcro (the soft "loop" part) and grey foam blocks are on the ends of the lane. The bags with the stars are simply cornhole bags cut down and resewn. There are counter sunk screws that hold the lanes to the track.
It works really well, cars simply plop to a drama-free stop no matter how fast or heavy they are.
It may help to post a photo in this thread of what you have currently set up
One simple but surprisingly effective thing I've seen done was to lay down strips of gaffer's/electrical tape after the finish line with gaps in between. Check out Diecast Street League as the example
On the face of it based on your description, I would shy away from sand, kitty litter or anything that could get caught up in wheels or the car interior if running modified cars is a goal. That said, it is heartening to hear that having a proper controlled runout is important to your track design! Forward-thinking!