Problem with spline Blueprint

Hi I’m trying to create an aiming system using a spline mesh for a projectile that arcs.

The problem I’m having is that the spline or the mesh is not doing what I want it to do and I don’t know why. That I’m trying to achieve is explained in this forum thread.

[Forum Thread][1]

This video shows the problem I’m having,

[You Tube Video][2]

the components on the blueprint consist of 2 spring arms and 3 spheres the position of which im using to set the world position of the spline points when the spline is spawned. 2 of these spheres are attached to the 2 spring arms which I adjust the length of and update the spline points location to as they move.

at begin play I add a new spline component and set its points using the world location of the 3 sphere components

I then add a spline mesh component between each spline point. I have set the spline mesh forward axis to Y and its start roll and end roll to -1.5708 which rotates it 90 degrees and faded it in the direction that the spline is facing for this particular mesh.

Then when an event is fires every tick I extend my spring arms a set amount which moves the spheres atatched to them. spring arm 2 which has the middle sphere on the end extends half as much as the last sphere and spring arm. I then set the points of my spline to the location of the spheres. In the case of the middle sphere I also add an extra height value to the x location.

I then set the spline mesh to match the local vocation and tangent of the spline.

I’m not sure where im going wrong but the adjustments made to the spline mesh are wrong when I run the game and open the gate that fires the event that drives the spring arm / spline adjustment.

also you may notice in the video that the actor is attached to the player pawn facing downwards, this didn’t happen until I add the spline adjustment event to the blueprint and I’m not sure what is happening.

Any help would be apreciated