Greetings, Shredderz! If you’re a regular reader of the blog by now you know that I have a soft spot for the Bonzer. The Bonzer is a board I have written up numerous times, and I don’t expect that to stop any time soon! As the title suggests, this post will focus on the dramatic concave that you see in early versions of the Bonzer. A friend read some of my earlier posts on the Campbell Brothers‘ iconic design, and was kind enough to send some close up shots of a few of the Bonzers he owns. Give him a follow on Instagram when you get a chance. He has an insane collection with a lot of gems from Santa Barbara-area shapers.

As you can see, the photos really give you a great idea of just how extreme the double concave is in the tail. Pictured above is a vintage Campbell Brothers Bonzer, which I would guess was shaped sometime during the Seventies. I’m still tripping out on the curvature of the fin box, which looks like it was modified to fit the bottom contours of the board.

The second board is a Bing Bonzer, which I think was also shaped during a similar time period. Check out those branded side bite fins! The tail of the board is practically scooped out, which would have helped create water flow out the back. I am far from an expert on fluid dynamics, though, so rather than butcher the science behind this influential design, I’ll instead refer you to Malcolm and Duncan Campbell’s helpful rundown on Bonzer mechanics.

Finally, you can see a comparison between the Bing Bonzer and the Campbell Brothers model at the very top of the page. As you can see, the two vintage Bonzers are extremely similar to one another, which shouldn’t come as a surprise, given that the Campbell Brothers actively worked on the Bing version alongside Bing Copeland and Mike Eaton.

Thanks to Jesse for supplying the pics for the post! And if you have any photos of any rad boards you’d like to see featured here, don’t hesitate to reach me by email, or DM me on Instagram.