swingforever, the only way to determine the correct lie angle is by using a dynamic measuring method. This is why the lie board was developed where the golfer actually hits real golf balls to see where the sole of the club is touching the ground as it comes through impact. Looking at your divots helps because it can be a good indicator that the lie is either correct or incorrect for you.
Here’s the problem with using finger to floor or wrist to floor measurements and also any other static lie angle measurement which basically do not work: when a golfer addresses the golf ball with a certain club, the golfer establishes a hand location or hand height. When the golfer swings the club, there is a significant amount of centrifugal force pulling on the golfer’s hands and arms from basically the weight of the clubhead and the distance the clubhead is from the golfer (read as club length). This centrifugal force changes the golfers hand position or hand height from the set-up position to the actual hand location at impact. For most golfers, the hands move more upright by approximately 1 1/2 degrees to sometimes over 3 degrees. Of course when the hands move more upright, you flatten the golf clubs lie angle relative to that particular golfer. The second thing that happens concerning the lie angle is that the clubheads center of gravity is not in-line with the centerline of the shaft when the club is swung. So, the centrifugal force we just talked about also now acts through the clubheads center of gravity location during the swing thus bending or bowing the shaft downward. This lowers the toe of the club thus flattening the lie angle. Using a #2 iron as an example it would be in the vicinity of 1 ½ to 2 degrees. The amount of lie flattening varies according to the shaft flex, shaft bend point, club length, swing speed and head weight. So, shaft flex is very important in determining the correct lie angle.
So, with all this shaft bending going on and the golfers hands moving from one position at address to another at impact, everything is trying to bring the toe down or flatten the lie angle. This is why the toe is always up at address on every club you hit a full shot with. Of course, the putter is not included in this. Now you can see why that the only way to overcome all the many variables affecting the lie angle in both the golf club and the golfer is to use a dynamic measuring method to find out exactly what the lie angle is at impact for any given golfer. The lie board fitting method is still the best way to do this. Finger tip to floor or wrist to floor is absolutely worthless in either fitting lie angle or club length. View anyone suspiciously who uses this if you are fitted. This is a convenience or show method only to make you think the clubfitter is knowledgeable.
The basic procedure to use a lie checking board is this: Put a piece of ½” wide black electrical tape on the sole of the iron. Using real golf balls, place one on the hard hitting surface of the lie angle board. Set up as you normally do and strike the shot. After the hit, look at the tape on the sole of the club and place a mark in the exact middle of the tapes smudge mark. If the clubhead did not hit the board on any swing, simply do it again until you get the mark. This smudge mark is where the tape actually touched the board. Next, either visually or with a ruler, place a pencil mark very low at the exact horizontal center of the clubface (measure ½ the width of the face lines). Now, place another pencil mark at the bottom of the face that corresponds to the location of the smudge mark center you placed on the sole. Next, measure the distance between the two marks. The lie needs to be adjusted 1 degree for every ¼” difference. If the mark is towards the toe, the lie angle needs to be flattened. If the mark is toward the heel the lie angle needs to be more upright.
I really like to check 3 irons in the set, say a #3 iron, #6 iron and a #9 iron. In this manner you are sort of double checking yourself. Fun stuff, give it a try and start hitting the ball where you are aiming.