[Tying2Fly]

I have been fly fishing for a few years now but often have something wrong in my casting technique and need some help. Sometimes I am ok and it all goes as planned, but then sometimes I have trouble with my fly and leader will land in a heap or pile up. I seam to have the most trouble when using my lighter rod and lines like my 4wt than when using a 5wt or even 7wt.

[mattnmtns]

It sounds like you are inadvertently making a pile or puddle cast. Basically it sounds like you may be making a low or very open back cast then dropping the tip of your rod before your line straightens out on your forward cast.

I am by no means a casting expert, maybe someone else will chime in.

[Silvercreek]

I suspect it is neither a pile or puddle cast. Puddle/pile is aimed high and then is a downward mend. It is a controlled cast in which the angler aims high above the target and collapses the cast on the target.

I may be wrong and only the caster can tell me but, it sounds like he is reverting to a "beginner's cast" from 9 to 3 o'clock, with a long round arc, and stopping too low on both the forward and back casts.

I suspect that the fly line hits the water well before the leader because the cast is directed down instead of forward. With pile/puddle, the cast is aimed high and not low. If I am right, the cast also has a very wide and inefficient loop formation due to the wide arc of the rod tip path. Another symptom is that the angler does not or cannot fully extend both the forward and backward loops before beginning a cast in the opposite direction. For example, he begins the forward cast before the backcast fully extends. Both lead to a lack of power and an inefficient cast.

Take a video of your casting motion. Look carefully at where you stop the rod tip both in the forward and backward direction, the path of the rod tip, the loop formation, and whether you allow the forward and backward loops to fully extend before reversing the direction of the cast.

If I am right use the video to correct your cast.

Another possibility is that you may just not be able to properly load the rod because you are casting at shorter distances. If you can you double haul, this will help load the rod at short distances.

If you have no way to video, an exercise you can do is to cast side arm. Look at your loop formation and tighten it up. Also see if you are fully extending both forward and backward cast before making the opposite cast. Make your casts at 180 degrees from each other, and practice laying both your forward and back casts down along a straight 180 degree line. Then move the casting back vertically once you can do it horizontally.

[streamer]

One of the mistakes I used to make (and still do when I'm tired) is to not put the hard stops in my forward cast and my backcast. Here's how it went:
I'd pop the line and fly free from the friction of the water and then I'd follow that line with my rod tip until I felt a little weight (the "load"). Then I'd push the rod tip forward AND THROUGH to the water rather than stopping the rod tip and THEN following the cast down to the surface.

Especially if you are not hard-stopping the rod tip on the forward cast, but instead pulling the cast down to the 9 o'clock position, you increase the arc of the cast, the direction of the cast is more up than out, and it falls down into a pile. Sound familiar? If so, just focus on the hard stop of the rod tip in both directions. That oughta help tighten your loops.

Streamer

[Silvercreek]

Streamer gives good advice. You have to STOP! the rod. A sluggist slowdown to a stop is a cast killer.