It doesn’t matter if you’ve got a rad, sustainable, wood fin if you have no way to attach it to your board.
With fins being Wave Arcade’s main focus, we had to develop a reliable way to craft bases for the different fin boxes we wanted to sell fins for.
After research on the web and musings in the garage, there are a lot of ways to go about this. Most of which prove semi-challenging. It started to make sense why you don’t see a whole ton of fully wood core surf fins. But, we already knew this wasn’t the quick and easy way to do things.
Think about it – most wood fins you’ll see are made using a thin wood veneer center that’s either layered up in fiberglass or made using RTM. While these fins still look pretty sweet, they don’t seem to capitalize on all of the flex, weight, and sustainability properties that a fin made of mostly wood does. These types of fins are still primarily resin and fiberglass.
Glass-on wood fins are much more manageable, but we’re not making boards to reliably test them out – yet.
Having our fins be mostly wood is key. It allows us to highly reduce the amount of glass and resin per fin as well as maintain wood from the fin base to tip. We believe this gives Wave Arcade fins unique performance characteristics that would typically only be found with a glassed-in wooden fin.
As far as we know, there’s no one else making fins like this all that frequently.
Method 1 – Wood Bases
The first attempt at crafting a fin base for our bamboo fins was to simply shape it out of the laminated bamboo sheet and glassing over it along with the rest of the fin.
This method has the benefit of looking great, having the core extend all the way through the fin, and being fairly easy to craft.
It came with some major downsides though. Sharp corners are difficult to glass around. Drilling any pin/screw holes present some major problems too. Additionally, if the fit is not right, any post clean-up and reshaping will likely require some more glassing. No bueno.
Method 2 – Silicone Base Molds
At first, method #2 seemed promising. I picked this one up on some old Swaylocks threads. It involves casting silicone caulking molds from the fin bases you want to build and using those molds to cast resin and fiberglass around a thin wood base tab.
This method would be great if you were making a few fins every once in a while, but once you start working in batches, things get challenging.
The silicone bases can be difficult to make themselves, and small irregularities between molds of the same fin base cause a lot of clean up work.
Canting fins presents a whole other challenge of jig making. The challenge is amplified by however many fins you want to make at once.
Lastly, this method produces comparatively weak bases to a traditional fiberglass fin. It is very difficult to ensure a proper ratio of glass to resin all around the wood tab and any points of stress for the base. They also looked sort of messy.
After making about 100 different types of fins with this method, we decided to ditch it and chalk them up to prototypes – which do surf great! (If you’re okay with a sketchy fitting fin). Ask for a free fin prototype if you see us around.
Method 3 – Fiberglass Layered Bases
The next method resulted in a cleaner looking base that was strong and maintained a good amount of a wood throughout the fin.
This method involved a few more steps, but resulted in wood fin base tabs that were superior to any other method we’ve tried at that point.
The bases for this method involve some processes similar to how most solid fiberglass fins are made.
Unfortunately, this method turned out to be extremely time and labor intensive. And it still required a good deal of post-processing to get the bases just right. A little refinement was necessary.
Method 4 – Fiberglass Layered Bases 2.0
We took Method #3 and decided to simplify it. Using glass panels layed up to the desired thickness, we craft our bases individually and join them with our foil, glassed, and finished fins.
This method results in super clean bases, that fit right without much processing fuss.
The big question mark that remained was base strength, but after some rigorous testing surfs we’re confident that these fin are comparable in strength to the fiberglass, resin-transfer, and composite fins you can buy off the shelf.
Now go buy some fins.