[kp91]

You have a very good chance of getting blow out when cutting across end grain. When milling all 4 sides of a rectangular piece, you go across the end grain, with the long grain, across the end grain, then the long. This allows the cut across the long grain to clean up anything blown out on the end grain pass.

Since you are doing a triangular piece, you have continuously varying grain. The suggestion of using a backer board is probably the simplest and best way to prevent this. Another easy way is to keep your piece long, so you can trim off the last 1/2 inch.

If you can post a picture of the entire shelf piece, I might be able to offer another suggestion.

 

[kp91]

thanks for posting the picture. Definitely using a backer board or leaving the piece long and trimming after profiling would solve the problem.

That is some good looking poplar. I personally, love the green tint parts, I actually try to include it during the build process.