Trim Path with sharp ends

You can also use the Taper  option present under Strokes. This is default and has been added to After Effects.

You can use the Start Length and End Length properties to control tapering (which means to get narrow or thin towards an end) at the Start/End points of the Stroke. 

Check out this article that goes over Tapering in detail:

https://helpx.adobe.com/after-effects/user-guide.html/after-effects/using/taper-shape-strokes.ug.html

Hi mSet_One,

Did you complete your motion graphics comp? What did you end up doing?

Thanks.

Kevin

You can't do this with a Shape layer but what I've done in the past is to use a pressure-sensitive brush to draw a tapered line. You'll need a steady hand and a wacom tablet to do it. Once you've drawn it you can then Auto-trace it onto a new Layer as a mask. Then Apply the Scribble effect and zero all the Stroke variation settings (as in the diagram) Animate the End value to make it reveal. You may need to also animate the Angle setting to get the leading edge to look right.

Hi after spending hours searching I now realize I can't use trim paths with a vector image with sharp ends

unfortunately this functionality is not native yet in Ae. the common term is "taper". we want taper strokes. ask for it here please: Feature Request/Bug Report Form

for workarounds there are various methods. here's some you may consider:

1. using a 3rd party plugin called "Trapcode 3d Stroke" that has a taper parameter

2. using a text layer or a complex rigged shape layers setup. see more information here: Re: Gradient Along Stroke

3. using a 3rd party plugin called BAO Boa: BAO Boa - aescripts + aeplugins - aescripts.com

Also is AE prone to weird crashes on Win10?

no. this has something to do with your setup. make sure your Ae is up to date, and if it still crashes be more specific as to when exactly.