Two recent videos from WWM’s Steve Quillian have highlighted the use of finger-guided rip cuts with a circular saw. This trick allows for narrow rip cuts without setting up any actual guides or jigs, so long as the cut is within about one inch wide. (I’ve never tried this cut myself so this width range may be off. UPDATE: Steve comments below that even wider rip cuts are possible, up to about 5 1/2 inches.)
This trick seems very useful in the field, and maybe in any situation where an absolutely straight edge is overkill or you also have a planer handy. Probably much faster/simpler than either setting up your table saw or clamping on a track saw jig.
Steve’s over in San Antonio, Texas this week replacing a fairly unique sash with a new Accoya copy. He needed to trim off some material on the stiles (vertical pieces), and used this finger-guide method to take off most of the waste material. Final trimming was done with an electric planer. The live video doesn’t show it clearly, so below is a close-up screenshot from another narrow rip showing where to place your hand (from one of Steve’s other sash fitting videos).
FamilyHandyman.com says this technique is safe as long as you grip the saw before turning it on and don’t release it until the blade stops.