Dirty Tires

Here is a method I use for making tire look dirty, where the dust and dirt collect in the treads.  To start I mix a slurry of water and pigments, in this case using Mig Dried Mud.  The slurry should not be to thick, I like to have it runny as to get into all the crevices.

Next is to coat the wheel with the slurry, making sure to get it into the crevices, treads, and all areas you want to have the dirt showing.  I also apply the slurry into the wheel wheel and bottom of model.









Then you have to let it dry, I usually give it about an hour.

After that you can rub off the excess, I use a my thumb or finger, to be able to get the right pressure
and have better control taking off just what I want.  You can also use a stiff brush to change the effect and pattern in some areas, like the hub.