Rounded pin tail 3 fin bonzer

Hi there,

I see in all the posts here that most of the 3 fin bonzers are made with a diamond tail or rounded diamond tail, witch is the classic design. I have one, it’s a 6’3" made by Sean Wilde, and is one of my favorite…

Now, I was considering making myself another 3 fin bonzer for bigger surf. I was thinking 6’8". I would use this board in big barrelling beachbreaks and was therefore wandering what the effect of making it a rounded pin tail ( instead of the diamond) would be.

Has any of you ever tried this? Would the fins placement have to be different?

Thanks for your help.


How big is the beach break your going to be surfing the board in? If its like head high and under you’ll get away with the diamond tail. Anything above that you should consider the rounded pin. Diamond tails are more stylish and add more of a retro feel. You might take that into consideration. If your a fast and fluent surfer you wont have to worry about the tail so much. They will both give you clean lines.

When it’s head to over head high, I’m doing OK with the 6’3" diamond tail… I would only use this board when the surf gets over 6’…

All of my singlefin boards have a round pin tail (with or without wing) But what would be the effect of the ventury concaves in a round pin? Wouldn’t the narrower water flow exit reduce the ventury effect?

any thoughts to a roundpin bonzer-5? seems like the 5-fin would be a better complement to the shape you’re going for and the conditions you want to put the board in. in fact, i’m getting ready to start one myself.

check out this little gem that lob just posted up…

For standard widths the fin placement does not change much. On that board 10.5" for the rear edge on the runner. Only on very gunny boards do you have to adjust the placement. (Bonzer diagram refers). But as has been said,5 fin is a better option unless you’re doing a light vehicle bonzer.

Fantastic work by Lob. Every line on that board is so clean.

Bye the way.

I still can’t get my head around how there can be a venturi effect in a hard bottom turn like this.


I tell you a secret: in that case is not for the Venturi effect

the concaves channels are also used to help the side runners and overall tail area to maintain the board grabbed without spinning…

That board looks great, and I understand that a bonzer 5 would be momre appropriate for what I’m planning to surf it into… the multi “channel like” conncaves and five fins would give more hold and allow one to go deeper in the tube.

But what I really like in the bonzer 3 is the fact that I can ride it as a single fin… I get this same kind of lines but with more speed and more hold.

Would the bonzer5 feel more like a truster?

If you like the 3 fin bonzer then make one. If your worried about it having a single fin on big waves then adjust the shape of the board accordingly. Make the rocker a little bit more extreme and pin out the tail. Jerry Lopez had no problem riding sigle fins at pipeline and I don’t think your riding waves like that. Make a 3 fin bonzer with the same shape as the one above. That would serve you fine. I would go with the channels if i was you.

If you haven’t already checked it out look at this website-

It’s onw of the guy’s who works (owns?) Moonlight Glassing, the folks who do most of the Campbell Bros boards. Lots of good stuff there. I liked this Bonzer3.

Look at this one! Bonzer 3 round pin with a great swirl. Looks to be about the size you’re looking for.

Now you’re speaking… that is exactly what I was thinking of. And this swirl!

Supreme, I was actually first thinking of 2+1 with deep channels, but got afraid of having to glass those (and lazy maybe…lol), but it’s funny that you’re saying that 'cause I just remembered a board of Tudor (check out the thread “Joel’s board” by goin left)

I’m gonna do a bit more of searching, refine a nice template, and I’ll keep you in touch on the project.

Thanks for all your usefull answers


Yea man definitely keep me posted as to what you decide on. Send me some pictures when you start shaping.