sanders

[schneiderkyle24]

what do they do in game if anything?

[thebear05]

Sanders are used to provide adhesion between the rail and the locomotive wheels when wheel slip occurs. All locomotives have sanders fitted. Wheel slip usually occurs when starting a train with too much throttle, too steep a grade or a very heavy train, as there is very little resistance between the locomotive wheels and the rails. The Climax tends to wheel slip above 90% throttle.

[Nighthawk29]

I've wondered if they actually do anything in game right now or not. I use them occasionally and it seems like they do help a bit, but it could just be my imagination.

[Knsgf]

Almost all engines in game never slip and thus sanders on them do nothing. Climax is the only exception currently.

[Schlappspaten]

Slipping is not always visible, just look at this Porter struggeling and then starting after sand application: https://m.youtube.com/watch?v=3MyNQ0AaM9k&t=1032s

I stopped there on purpose to demonstrate the importance of low gradients, the astonishing pulling power and the use of sand. Oh, and longer trains are fun... (with physics on realistic of course)
Edit: the link points directly to the starting manoeuver and skips about 16m30s