anyone attached a small straw to a rattle-can?

Can't do it. Paint can nozzles are different from the lubricant ones that you can attach the extension. Even if you are able to switch nozzles the paint will be too concentrated and will run.

You woudn't gain any control by attaching a straw. If you want to control you will need an airbrush. If you still want to use the paint from the spray can decant the paint and shoot it through an airbrush.

lambing wrote:

There is so much overspray with a rattle can, I was thinking of attaching a thin straw (like on a WD-40 can) to the rattle can nozzle in order to cut down on waste and control where the paint goes. anyone ever tried it?

I would only use a tube like that to use with lubricants, paint would be a very bad idea.  If you don't wanna waste paint, get a gravity feed airbrush.

That might work for decanting paint from a spray can for airbrushing or touching up with a brush, but I'd advise against trying to actually paint something using that method.

Also, you may note that when you spray WD-40 "straight" without the extension, you get the usual fine mist, but when using the extension it can often be less finely atomised, stream-like and "splattery" .

Definitely not a good idea.