Deck Seams Kerf Width

Ready for new decking on a ‘52 Riviera and original planks look to be closer to 3/32”. Some of the curved seams looked to have hand carved tooling marks - they are original. I’ve read references to 1/8”. I have both kerf width blades so no issue.

Pros and cons to each, if any? The edges should be broken slightly, as I understand it, during sanding.

This has been bounced about a good number of times. One thing we know for sure is that with each restoration that a boat goes through the seams get a bit wider due to reefing out the old caulk, and then attempting to clean up the edges. There are many ways of cleaning out these old seams— I have literally heard of hack saw blades to carpet knives, and everything in between.

If you happen to see a restored boat or two at a show, the seams range from a scant 1/8" to over a quarter. I have seen some that were as white as the sun and approaching 5/16" in width.

A number of years ago, an almost original pre war Barrelback was found in New Hampshire. This boat had never been refinished—still had original hull side script, original oxidized varnish, and original plank seams. The boat had been kept in a boathouse with a fair amount of humidity, so the planks were very true to their original dimensions. The seams on this boat were about .077 or on the shy side of 3/32.

Now—I can’t speak much for post war boats, but I am thinking they would be similar. I would personally stay around 3/32" max knowing full well that they will grow over time.

The seams were generally done by machine. There are certain models, such as the post war Riveieras, and 20’ Custom, where it is widely believed the seams were waterfalled over the transom by hand cutting.

Thank for the thorough response. I will go with the 3/32.