Dry vs Wet sanding

As for me, I pretty much always wet sand.  The only time I don't is when something might be damaged by water.  It helps the sandpaper (or whatever you're using for sanding) work more effectively because its not getting gummed up with sanding dust.  That sanding dust that gums things up can also build up and cause gouges and scratches on your model, depending on the material that's gumming it up.  I usually bring my sanding to my kitchen sink and do it with running water whenever possible.

Hi Nickg;

 "Wet Sanding " is just it says. You sand the object of your work( Frustration?) under a gentle stream of water( temp to suit you, NOT HOT). What this does is cause the usual dust from sanding, which would clog the paper, From doing just that. That way your sanding is smoother and much more to give you a truly smooth finish.

   Dry sanding is alright with wood. With plastic it clogs the paper. Why? Well dry sanding generates heat. Generates heat? Yup. From the friction you make rubbing the abrasive over the surface. The clogs then mess up real fine work. The answer? Wet Sand anytime you can! Also, on some surfaces you want to sand in a circular pattern. Dry Sanding Does not like that. Clogging quicker and wasting paper.

Eaglecash867 & Tanker-Builder

Great! I just learned something new. Thanks.

Just an additional note if you wet sand over the kitchen sink.  Its always a good idea to put a wire mesh strainer over the opening to the garbage disposal, just in case you drop something.  Not fun trying to dig small parts out of the garbage disposal, especially if you have big hands.  

As a general rule, if you're sanding to remove material...gross shaping...that would best be done dry.

If you're sanding to finish...smoothing a surface, removing fine scratches and that sort of thing...that's always best as wet sanding. In some cases, depending on the material being sanded, the wet-sanded material may actually act as an additional fine abrasive to polish out your finish.

gregbale

As a general rule, if you're sanding to remove material...gross shaping...that would best be done dry.

If you're sanding to finish...smoothing a surface, removing fine scratches and that sort of thing...that's always best as wet sanding. In some cases, depending on the material being sanded, the wet-sanded material may actually act as an additional fine abrasive to polish out your finish.

 

thank you for the clarification. 

And...as an addendum to TB's description...I'd point out that it doesn't have to be done under running water over the sink.

I usually do my wet-sanding with a little margarine tub of warm water at my workbench, just dipping the sandpaper occasionally as needed. Just be sure to give your part a good rinse or rub-down with a clean cloth when finished.