https://www.bodyshopbusiness.com/common-sense-spray-gun-tips/

I have a selection of tips which I use depending on what I am spraying. I also have three or four different guns, primer, finish, trim and clear coat. There is no ONE tip which serves all purposes/paints. It's a matter of experimentation to get the exact finish you want. I think you will be disappointed/unhappy using the .8 for the prime coat on the inner fenders. You'll get a lot of "mist" and not really the coverage you are looking for.

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