I’ve been thinking something like this might work. I’ll find out in the next couple of weeks.
I’ve never had a great way to rough cut risers that had fiberglass or G10 in them, whether as accent stripes or an I-beam.
I used to use a jig saw or band saw as much as I could while trying to stay away from the composites.
Not willing to spend $145 on a carbide tipped blade, I ordered one of these portable bandsaws for $100. They cut steel, brass, aluminum, fiberglass, etc.
Built a stand with dust collection out of scrap plywood and hopefully off to the races.
Fingers crossed.