I'm trying to make my reins more comfortable. They're kind of stiff. Should I soak them in oil over night or something like that? My son is 6 and is learning to ride and the stiff reins seem to be making it hard for him to grip them.
Also are there any reins especially for tiny hands?
NO SOAKING! It won't make the leather explode or anything but it will shorten its life and make it weaker, meaning it could break when your son is riding. Not something you want.
My fave product is Hydrophane leather dressing. Get a paintbrush, and paint a thin coat on the reins, both sides, and then while it's still wet, gently roll the reins back and forth. If the oil soaks in immediately, don't roll it yet. It's too dry and will crack or weaken the fibers. Continue painting on thin coats until it doesn't soak in immediately. Then roll back and forth. If oil is present on the surface for more than 30 min. or so, you've oiled enough and you should wipe off the rest with a towel.
Rolling with the oil on it is the key to softening leather. All my tack is butter soft. I mean soft. The added bonus to Hydrophane is that it waterproofs as well, and doesn't leave that icky gooey residue behind.
ETA: They do make thinner width reins for little hands, but they're usually pony-length. There are curb reins like you'd use with a pelham, they are 1/2" width but are not laced so they will probably slip thru his little hands. If you do some digging, you may be able to find 1/2" wide reins somewhere, but I can't think of anywhere off hand.