Not sure I'm missing it and hasn't come up till now...which skill is used

In all the cases I can think of, Ranged (Light) covers the skill. Other than grenades, there aren't all that many thrown weapons. If you're talking about thrown weapons like tomahawks or boomerangs, the only precedent I can think of in-game is the ascian throwing daggers: they rely on Ranged (Light), but you add your ranks in Brawn to the damage.

There is precedent for these types of weapons in the game. One example I can think of is the Age of Rebellion adventure "Operation: Shadowpoint," where Onderonian Beast Riders have javelins. There, it seems as if the javelins use a static damage rating, but I would prefer them to be linked to the throwing character's Brawn like Blackbird suggests.

There is also the Ascian Throwing Dagger, which has a +1 damage rating and doesn't add a difficulty die when engaged, which is nice, and also something I'd do with normal "throwing" weapons like axes, etc.

I'm not sure if there are any other examples...but that should give you a good start anyway.

Thanks will have to look up the weapons damage

In all the cases I can think of, Ranged (Light) covers the skill. Other than grenades, there aren't all that many thrown weapons. If you're talking about thrown weapons like tomahawks or boomerangs, the only precedent I can think of in-game is the ascian throwing daggers: they rely on Ranged (Light), but you add your ranks in Brawn to the damage.

I think an argument could be made that throwing large rocks or cabers might be Ranged (Heavy), but since that's usually something done with the Force rather than muscles, the point is probably moot.

I think an argument could be made that throwing large rocks or cabers might be Ranged (Heavy)...

on Ranged (Light), but you add your ranks in Brawn to the damage.

Yeah, if you used two hands to throw something heavy , I'd totally go Ranged (Heavy).