Dear all, in terms of weathering what is the different between Odorless Thinner and White Spirit? Than you!

As far as i know, they are pretty much the same thing except that white spirits might be abit stronger

Richards right odourless is less 'HOT' keep white spirit for cleaning brushes.

Not exactly guys. White Spirit and Mineral Spirits are the same product, just different names depending on where you are. Odorless of either is more refined to remove the detectable vapors from it and thus the strong smell. Odorless do seem a bit more mild and are better for model work.
You can buy it inexpensively in gallon jugs at WalMart or any big box store. Klean Strip Odorless Mineral Spirits is the brand I use. A gallon jug lasts years.

How about turpentine ? Grumbacher makes both an odorless thinner and turpentine . What would it's uses be ?

Evaporating too much of your money! First, turpentine is a wood product, and is gummy, thick, and too harsh for use in model building. In many cases it will never dry on the model.
It's not necessary to spend extra money on Grumbacher and always use mineral or white spirits, NOT turpentine. There are good thinners that work as well or better for a lot less.

Matt, you may be thinking of gum turpentine which I believe is used for making furniture polish (as well as a bizarre sounding ingredient in self-medications for supposed ailments). Artists' turpentine is certainly thin (though it can become thick if it goes off) and actually more volatile than mineral (white) spirit, so it dries faster. It has been the traditional thinner used by artists for oil paint, though I think it may be falling out of favour due to recognition of its extreme volatility and potential effects on health.

You are correct however that there is no need to spend the money on it and that it has no particular advantage for modellers, unless you favour a diluent that evaporates extremely fast. (If you do use it ensure adequate ventilation and possibly a vapour mask.) No doubt there are oil painters who swear that it is necessary for certain things.

Both white (mineral) spirit and the odourless thinners are also potentially hazardous - although with the latter there is very little smell, it is still turning in to vapour at quite a rapid rate, if not being quite as volatile as the former, and less so than the genuine turpentine.

Matt,

Perhaps gummy was a bad description. Artist's turpentine is however too harsh for use on models and when mixed with oils or enamels, it has been known never to dry on occasion.
Turpentine is distilled from wood. Mineral Spirit is distilled from petroleum.
Mineral Spirits are a "thinner thinner" and will give the best results on models, whatever you use it for.