[img_assist|nid=1047255|title=Hansen logo on 9'5" Powerflex|desc=Logo on Hansen 9'5" Powerflex|link=none|align=left|width=0|height=0]I'm working on restoring a Hansen Powerflex. The existing fin seems too brittle to be useable so I'd like to find a new fin which will fit in the original "Wonderbolt" fin box. Found some helpful info within the forum including contact info for Juan Rodriquez of One World Surf Designs (I have e-mailed him). I also found the great info on how to shape and laminate a bamboo fin which I'm tempted to try.
[img_assist|nid=1047256|title=Hansen 9'5" Powerflex with Wonderbolt fin box|desc=Hansen 9'5" Powerflex with Wonderbolt fin box|link=none|align=left|width=0|height=0]
There was some discussion about the Hansen "Wonderbolt" system and fin box but I did not see any pictures so here are a few.
[img_assist|nid=1047254|title=Hansen Powerflex with Wonderbolt fin box|desc=|link=none|align=left|width=0|height=0]I also read a few posts by people who did not have the original polypropelyne fin so here is a picture showing what's on my board. I'm not sure if this fin is the original wondering if it look like the real deal to you experts... this shape does not seem to show up in any of the pictures or info I have been able to dig up.
[img_assist|nid=1047258|title=Hansen 9'5" Powerflex fin for Wonderbolt fin box profile view with scale|desc=|link=none|align=left|width=0|height=0]
A profile picture with a scale included. The tip of this fin is not complete.
[img_assist|nid=1047257|title=Hansen 9'5" Powerflex with Wonderbolt fin bolt top view|desc=Top view of Hansen wonderbolt fin bolt from 9'5" Powerflex|link=none|align=left|width=0|height=0]
My board has some markings on the top side near the fin bolt but they are not legible. Does anybody have an idea when this board was made?
The ''markings'' by the bolt, on the deck, is the board number, and the last character appears to be a letter ''C''. The letter C was the symbol used Bill (Willy) Clark, one of the group of shapers at Hansen, when I was shaping there. The board was probably made in the 1966/67 time frame. The fin does not appear to be original, or at least it has been modified.
If you are looking for a replacement fin, don’t go asking around for a “wonder bolt” style because that is not what you have. Wonder bolt was a term used by Dewey Weber for his proprietary fin system in the mid 60s. He was the only one to use it. Con had a fin system that was similar, but the two aren’t interchangeable. The fin on your board is specific to the Hansen brand. When removable fins first became common, just about every major brand had their own system. This was roughly '65 to '67. Fins Unlimited and WAVESET changed all that around '68.
That looks like an original fin that’s been worn away at the tip. I had a Hobie with a fin made from the same material and it had that same ‘flaky’ appearance. Pretty sure it’s polypropelene which becomes brittle with age. It is rare to find one of those fins in decent condition. Even when they were new, we’d snap them off by turning hard when the water was really cold ( below 40f)
I copied and pasted, then removed “.thumbnail” and the image appeared full size. Why I am seeing thumbnails, only, and they don’t seem to link to the full size image file?
Thanks for the inputs on my Hansen fin. I found another picture on the web of a '66 Hansen 50/50 with a glassed on Pivot fin. By scaling up the drawing and printing it at similar size to the fin on my board I was amazed to find that the angles of the straight portions of the leading and trailing edges match perfectly. My conclusion is that the fin may be an original in the Hansen Pivot profile using the Hydro-Wedge finbox.
I'm in progress now attempting to make a replacement with a plywood core, brass threaded insert and a clear laminated halo.
