Arc welding rods

What's the best size and number welding rod to use when welding 1/8" mild steel? Is there a chart somewhere I could get to see what rod works best in what situation? Thanks

I use 3/32 diameter rod in a 7018.... I have a DC welder.. Do 90% of the welds with that DC welder and 90% of the welds with that rod.. I weld anything from 1/8 inch to 3/4 inch with that rod.. I dont do anything really BIG... If was making a loader bucket and the bottom was 5/8 inch thick i would get some 1/8 inch or 5/32 diameter rod for that... but for  brackets / trailer / 3 point hitch / misc anything,... i use the 3/32 with multiple passes.... the thing with 7018 rod is it has to be kept DRY... its a low hydrogen rod.. I have a small refrig 2 cubic feet with a 10 watt light inside.. Seems to do just fine..... 7014 should be similar, but not LOW HYDROGEN, so not as critical on heat.

one thing about the 7018 rod on DC is the flue lays easy ontop of the weld.. A chipping hammer will knock it off easy in a few seconds............ sometimes using a 6011 or 6013 rod you will get the flux STUCK in the weld and harder to get it chipped off... especially on AC welders............ you have LESS flexibility with an AC welder.

 This site has a lot of info. and videos on all kinds of welding. 

1/8 rod size is nain thing I use if stick welding and 6011 rod on most things 
 1/8 - 7018 also if new metals and can position the project for weld direction 

7018 is a low hydrogen rod... it will suck up humidity of left on the shelf in the garage.. Spec says to put it in a welding over and maintain it at 250- 300 degrees, but i have a 2 cubic foot refrig with a small light bulb that keeps it around 120 degrees and that seems to work real good.... I have had rods in there for a year and they weld fine... but your right, you can NOT leave them set on the open shelf.

I like the stuff called Super Missell Weld anybody can use it. DC welder works nice.

How come nobody's mentioned JB Weld?  REAL easy to use and no AC or DC.

two standbys 7018 and 6010 5p +  

Good thread, I've been welding my own stuff since high school, and do a better job with my stick welder than my wire one but it is just for light stuff.  Several years ago I picked up a Lincoln tombstone AC/DC off craigslist because I was going to use it to remove rust from a trailer frame with a big electrolysis tank.  With the suggestions made, I'm going to have to try the DC side for welding.

6010 and 7018 are what is always around.  Not that I know much,but if I can get to it with out doing it over head,it general stays as long as the original. Sometimes even longer.

For 1/8" steel  I would use 5/64ths rod.

7014 is the primary rod I use.  I sometimes use alloy 1000 from Blue Demon but I only buy it if it is on sale because it is spendy.  For poor quality metal I use 6011.

 I run a DC inverter stick welder from Longevity.

There are several booklets you can pick up from welding supply houses putout by rod suppliers that give a good overall use guide for their rods and use of them for general welding and specialty welding . 
 Certanium Rods sales guy came into shop and had me try a few of their rods - said could cut down on different rods needed and stock fewer types by switching to theirs . Problem was it was 4 times the cost of present stock .  
 On DC 6010 P but 6011 AC gives similar weld character , 7018 AC by ESAP gave me good results for years and when i welded new grouser bars on tracks of my HD5 and D6 I used 7024 drag rod .
 now with my Pow-Con machine (Thermal -Arc) inverter welder or my Miller 304 I can wire feed, TIG, or SMAW in either polarity with one machine and have output of over 180 Amp . E70S wire for most work using .035 wire .
 Problem is all welding supplies have went out of site on cost be it shield gas or wire itself.