How best to clean dusty gritty negs?

[Gadget]

Agree with purlin and Ray T.

Drying  would depend on whether the negs are separate or on a roll/in strips. We had a drying cabinet with film clips at college but I later rigged up a little clean cabinet and some string as a line and little tiny clothes pegs.

Gadget

[Ray T]

The 35mm ones should be in strips and it's unlikely there will be much space at the end to attach a film clip (or other fabricated device) but you have holes all the way down the edges that you can use to hang the strip. A paperclip with a small weight on the end hung at the opposite end should stop them curling.

Photoflow etc. (or well diluted washing up liquid) will help prevent streaks but I gave up wetting agents for methylated spirits as a last wash. It dissipates the water and drys very quickly. I'm told that press labs used to use it when speed was of the escence to meet deadlines.

It does sound that the o/p is going to have greater problems though. A pre-soak in slightly soapy water might help.