Looks like a #3. You can do a great deal with a jack and a smoother. If you want to get the most out of them, i recommend the Rex Mill website (
www.rexmill.com). There's some great information on sharpening and tuning them to get the most from them. If you're not familiar with using planes, starting with a dull tool that's out of adjustment will cause you to pick up drinking and cussing habbits until you finally swear them off after a 12 step program.
Taking an evening to clean up the plane, sharpen it, and finely adjust it will do two things for you. First you'll be really familiar with your tool before you really rely on it to work well. Additionally, the tool will be capable of precise predictable work.
Once sharp and tuned, grab a piece of scrap or two and start going to town. Play with the settings so you know how it responds.
One mistake a lot of people make is setting the lever cap too tight. You should be able to adjust the depth of the cutting iron without loosening the lever cap. If you over-tighten the lever cap, you're puting tremendous stress on the frog casting (the piec the cutter/chip breaker assembly seats on). Iron is brittle and it does crack.
In general, the main issues with tuning a plane are sharpening the iron, adjusting the chip breaker so that it seats properly at the cutting end of the cutting iron, seating the tote and knob snug to the sole casting, making sure the toe, throat, and heel register flat along a straight edge, setting the throat opening properly, and making sure the frog seats flat to the sole. Rex Mill explains how to do all of this. The main goal is to have a tool that can be finely adjusted and works without chattering.
If you wind up liking hand planing, an aftermarket thicker A2 cutting iron and possibly an aftermarket chip breaker will go a long way to reducing chatter and reducing the time between sharpenings.
Have fun with it. I developed a strong appreciation for hand planes after picking up my first $10 smoother at a flea market.
Paul Hubbman