(04-10-2020, 09:42 AM)Hank Knight Wrote: Spiral bits cut with a shearing action and generally yield cleaner cuts than straight bits. They can still tear out chunks of the workpiece when used with reversing grain direction. The bit I used on my desk apron is a hybrid spiral bit called a "compression" bit. It has more cutting edges than a standard spiral but and they are arranged so they compress the wood from the top and the bottom toward the middle as they cut. This dramatically reduces the chance of tear-out. The downside is that they are expensive. The apron and feet on my desk had grain running in every direction. I had one chance to get the cut right and I couldn't afford to risk tear-out. For me, this was justification enough for the purchase of the bit. It was well worth the cost; it did a beautiful job with absolutely no tear-out.  Here's a photo of my Whiteside compression bit.

9D6169EE-9183-4F46-88FF-EF661A751FF8 by Hank Knight, on Flickr

NOTE: The bit wasn't much help carving the feet. Like any edge trim bit, it only works on flat 90 degree edges. I used it only for flush trimming the apron and as much of the feet as I could. When the router base encountered the up-curve of the feet, I stopped the cut and finished the job with a block plane and scrapers.