Hello and welcome, we were all new to this at one time, much help can be found here for developing your skill and craft of picking for the enthusiast, not so much for opening locks that are actually securing something. I am sure you can appreciate the distinction. Otherwise we are here to help and promote the positive aspects of lock picking.
Those 40mm Ace hardware padlocks have security spool pins inside. Although they look like they would be as simple as a master lock, they aren't. Search around the forums and youtube on picking and defeating spool pins.
Spool pins are a fun bunch to pick.... just ease up on the tension and work it slowly up (you should feel your tension wrench rotating backwards) ease it slowly or you will probably drop all the other pins and over set that pin.
Watch BosnianBill on youtube, he talks through his entire video and describes what he is feeling and what is happening..
have fun and keep to easy locks at first so you dont get discouraged.. Ask questions and watch videos.
I picked another similar 40mm china lock but that one gave me trouble aswell. 
