re: Spline material

That’s a fine saw for removing the excess barb, just be careful as you cut since it’s prone to chipping off the corner of the grain allows it. As has been mentioned, cut from the raw side in. As has also been mentioned, blue tape is a good idea. I’d mask off the sides with tape before using the flush cut saw so you don’t accidentally knick the side with an errant tooth. Sand to finish.