Iron Ring Rapid
Not far downstream of Shipwreck Rock Rapid, you will encounter some slack water passing through a series of boulders. Iron Ring Rapid is the first major horizon line that you will encounter as the river bends sharply to the right. There is a pool on the left at the top and a large shelfy ledge on the left bank. It's a great place to get out and take a look at the rapid and also the easiest portage.
Aside from walking, there's really only one line through this one, and either you're on it or you're going to wish that you were. That goes for about any water level though obstacles and river dynamics change drastically with volume. As you look at the top of the first drop, your attention should be directed to the large slanted mossy boulder on the right shore.
Water washes up onto this slanted undercut and then funnels down the first drop. Most rafts will enter very close to the left shore and drive straight for the downstream edge of the undercut. At fall flow as you enter here with a raft, you will notice two fluffy waves in the channel. If you put your left tube on both of these as you're driving to the right you're probably on line. At fall levels, provided that you are somewhat on line, the current will most likely push you through the second drop with no effort of your own.
It is at lower water levels that things begin to get more complicated and your margin of error gets extremely thin. The bottom of the First Drop changes from a sweeping tongue of water to a steep and trashy hole that offers upright passage to only perfectly placed boats, and the out wash of the hole directs not toward the Second Drop, but to the left and toward Woodstock Rock, quickly and with great force. Remember, Iron Ring was once coined a Class VI for a reason! There is a big eddy below the rapid to the left and undercuts on the right.