Sheet metal bed floor

For those of you that have built a new bedfloor, did you spray the bottom side of the sheet metal with anything before welding it in? Just wondering if I should spray mine with some weld through primer, just to slow down the rust process. Don't know if thats really a big deal or not, just looking for some opinions.

yes spray primernt he underside

whats up man im in the process of doin mine now. what im doing is spraying weld through on my welded edges then comming back across the whole underside with dp40 its a ppg metal etch then im weldin it in...dont know if its the right way after its all in there ima come back from the bottom as best i can with some black singlestage of somesort to seal it...then i'll prolly just undercoat the shit out of it. but dont undercoat before you weld in or directly on top of primer, cause the undercaot will burn and it absorbs moisture...but oh well just my two cents...by the way how is everyone smoothing out there seams i was just plannin on knockin down the welds and seam sealin it since its gettin rhino lined..and suggestions on another way do ya'll knock em all the way down and putty them? just wonderin...

I turned my bed up on end on sprayed it with rustoleum once everything was welded up. I wouldn't spray it before you weld it though.

mine came out real good by seamsealing all the bottom,i used 1&1/4 square tube and did every joint under the bed after cleaning it w/denatured alchohol,then sprayed it w/rustoleum red oxide primer,then satin black (same co.) for the top welds use a flap disk on the welds then seamseal!