Before I post the following question I apologize if this isn't the correct board to ask, but I was not sure which one because it relates to techniques, baits, and electronics so I figured the general forum would be the best place...  

 

 

So, lets say I scan an area with my Garmin 93 UHD and I'm using my side scan/down scan and I see a good looking brush pile... I bring up my curser and mark it with a way point with my curser crosshairs to mark it's exact location as opposed to my boat position so I feel confident I have the true location of the pile marked..  I turn around and zoom in on my mapping to bring up my boat icon with the alignment mark (40 ft.  to be exact) out from the bow of the boat and my rings around the boat to pull up directly in front of the waypoint so that I can begin fishing the area. I make several long casts out in front of me using texas rigs, deep cranks, jigs, etc to attempt to hit the pile.... Problem is - I can never seem to hit the pile no matter what I do.....    Would anyone be willing to give maybe better advice on a way to get yourself lined up for brush or other targets that you want to fish? 

Zoom in all the way before marking waypoints with a cursor, or you WILL be a curser, many units will distort or add error if you are zoomed out. Also practice with known distances to determine what is causing the offset.

I used to circle around to check the accuracy of the waypoint and if necessary replace it with one using 2D sonar.
 

Now I use MEGA 360 and MEGA Live to find the brush pile before I cast but that’s probably cheating.  ?

Find a brush pile or something that you can drop a marker bouey on...  Then practice scanning the brush pile, dropping a waypoint, then lining up to the waypoint and casting... If your waypoints aren't being set accurately, you will know pretty soon by doing this...

Are you sure your bow is pointed at the brush pile?  Your boat icon can be pointing any direction if you are not moving.  The bow of your boat can be pointed one direction, and the bow on the boat icon can be pointed the opposite way.  Try using marker buoys, then as you gain confidence in your unit, graduate to using only your electronics.

Throw a bait with an exposed hook, it'll find every brushpile in the whole lake.

When I'm damiki fishing in the winter, I feel like Paul Bunyon chopping down all the brush

But I'm directly above it, so no pendulum effect

 

You can also try a heavier weight as it might be falling away from the brush before getting to it.

Your crank bait may not be getting to total depth do to line size, speed and casting distance. You may be running right over it just not getting to the depth. Find a spot on the shore to line up your cast with as well that puts your brush pile between you and it, then you can triangulate yourself.

On the Garmin Echomap units you have to make sure you're dropping the waypoint on the cursor and not the boat position. It actually takes an extra step to ensure the waypoint is on the cursor. There is an icon on the top right of the screen to put the waypoint on the cursor rather than boat position.