I am trying to mount a roller shade in between two wood beams on my porch. The problem is that the beams are a hair too close together to accommodate mounting the shade.
I am trying to remove a small amount of material (~1/4") from the side of each wood beam, about 3 inches deep. I've illustrated the problem on this picture.
I'm unsure which tool or approach would be best to complete this job. I've considered a few ideas:
A straight router cut with a guide on the outside could do it, but the depth of cut I need extends past the capacity of most routers. I suppose I could hammer it out with a chisel but it would take a lot of effort. Another idea I considered was using a power planer to shave off material in large passes, but that approach poses problems considering I'm trying to remove material to a specific depth.
Anyone have suggestions?