well, i have no clue why you would talent for Defensive Mastery & Harden Skin. It's never worth it in anyone's opinion to waste 2 talent points to stop 2 monster damage(concidering they deal 40-100), not to mention wasting 3 points to stop 2 physical damage(Harden Skin). There is also no reason whatsoever that singed would need a Pickaxe. AD builds for him completely go against his play style, which is based around his poison. I'm pretty sure you screwed up on his runes too, seeing as he in no way whatsoever needs .78 crit damage.

To be full honest, this build seems almost to be a troll post. Take a look at other builds for singed before making your own. But when you try to make another one, don't copy someone else's build. You can have the same ideas, but they give you the build description space for a reason. Use it.