Spring loaded fin for rocks/shallows/flatwater/rivers

[deepmud]

I've been thinking on a solution to the problem of the "sudden stop" problem of hitting rocks/logs while paddling - not an issue for surfing, but those of us in little streams and extensive shallows (fishing?) this is a pain. I found this option just this morning while trying to find pics of the Coreban river-fin that was put on the back of iSups with glue-on mounting nuts and such...

This uses a standard fin box. How great is that?

No idea how well it tracks - but seems like it can't be much worse than a rubber fin. Pretty clever idea - and if your other option is "no fin at all" it might be wonderful. I'm very tempted to try one.

https://www.amazon.com/SUP-River-Fin-Pivoting-Shallow/dp/B01JDTJW8O

http://www.frogfishfins.com/



EDIT: added a PIC - linked from their site:

[deepmud]

I did a quick search - no Hala Stompbox posted up either - this is built into the Hala board,it's a cool option, but no way to retro-fit, and no way to add it to a standard hard board. It does go COMPLETELY flat, but I find with an iSup at least, the bump of the fin box that sticks out will be higher in the water than the middle of the board squished by my weight - if I can float over a log, my finless (pulled the fin for the creek) finbox will clear it too.

[sailwave]

Fantastic idea and oh so needed! 11.5" seems larger than what it needs to be for for most activities and rider sizes.  I would think a 7" should be added to the product line. Hats off to innovation!

[deepmud]

I'd like to know the square-inches to better compare to others - but my guess-timate is that it is similar to a Futures Keel fin? It has to be narrow to lay back, so they made it longer to make up the area - figuring that it won't matter what you hit since it fold.

No reason  you can't just cut it shorter tho', I think.

[deepmud]

borrowed stills from their video - shows the action - it just hops/clicks across the bottom and folds on the big rocks nicely.

[capobeachboy]

I bought a bunch of Corran's tail mount kick-up fins for ULI when he left for Canada. Slater Trout told me he mounted one on his 12'6" Boardworks for the Dusi race in SA and that helped him win the race as it was very low water that year. You can retrofit them to an inflatable or a hard board and they are removable. I thought it was a great idea as I've run rivers on ULI inflatables finless and had the 3/4" drop on the single fin box catch on a rock and send me flying. Anyway, they're still around and a great option for low-water paddling.  PM me if you want to buy one.

[PonoBill]

The fin on the Hobie Mirage Eclipse is sprung, and it's a rudder! Doesn't get as much out of the way as that tall, skinny thing would, but it shrugs off rocks.

[deepmud]

Bump - anyone who has been tossed onto their face this spring - I'd pm Capobeachboy or get ahold of frogfish  for a no-parts/bolts option and go up some creeks.

[Weeble]

interesting.  I'm wondering how it would perform on a race board.  I currently run a Futures 10" weed fin on either my 14 Bark (for touring) and my JP Australia 14 Open Water Race, so the shape isn't that much different, but I wonder about the base.  I wouldn't use it for ocean paddling of course, but when we race train in our intracoastal, or go touring on the intracoastal or Florida Keys, sometimes run into stuff just under the surface.  Our Intra-coastal is famous for pallets, and giant palm fronds, plus some other various chunks of something.  Down in the Florida Keys, It gets pretty shallow around some of the islands and rocky.  Last weekend while touring around up in West Palm Beach, as we approached an island that we were meeting friends at, there was a submerged tree trunk.  The tide was moving so that shallows were murky.  About 10 feet from the beach, my fin caught it and threw me down hard. 

[2Rivers]

I bought a bunch of Corran's tail mount kick-up fins for ULI when he left for Canada. Slater Trout told me he mounted one on his 12'6" Boardworks for the Dusi race in SA and that helped him win the race as it was very low water that year. You can retrofit them to an inflatable or a hard board and they are removable. I thought it was a great idea as I've run rivers on ULI inflatables finless and had the 3/4" drop on the single fin box catch on a rock and send me flying. Anyway, they're still around and a great option for low-water paddling.  PM me if you want to buy one.

I'm not sure, but some may be available through Riot as well...
http://riotsups.com/flip-up-skeg/

[Weeble]

So I ordered one and it came in yesterday.  It uses two fin screws, one in the front and one in the rear of the fin.  I'm hoping to try it out tonight, but if not, I'll be going to Sanibel Island this weekend and I'll give it go there.  I don't do white water paddling, but I am looking for a fin that does well for touring when it can get shallow such as around Sanibel or down in the Florida Keys.  It's no fun catching a rock, or other submerge debris.  Also, down in the Florida keys, with the tide changes, you can find yourself in some shallow areas.  I'm just hoping the fin tracks decently in normal water.  I'll post after I get a chance to take it for a paddle.

[deepmud]

I'm interested to hear how it turns out - please report!

I've been working on a home-built solution that works with my inflatables - kind of like the Corran. It's super nice not to get tossed on your face and in heavy weeds it swings back too.

[Weeble]

Okay, so I got to use the fin twice this past weekend over in Sanibel Island on the SW coast of Florida.  My main hope for this fin was that it would do "okay" for touring.  Down in south Florida, we will do some fun, full day paddles in various areas, many of which it's our first time paddling in, so we will run into some shallow spots, or areas with a lot of debris just under the water, or even down in the Florida Keys, where there can be a lot of rocks/ old dead coral.  A few weeks back while on a fun paddle, I caught a submerged tree with my fin, and I went down hard on the board and then bounced off into the water.  So, I was looking for something that would help in that regard.  I used the fin on my Bark Laird Race 14 x 29.5 that weighs about 33 lbs.  This is my Cadillac used for touring.  Our first paddle was a beach launch from Sanibel with a short run down to canal that took us back into the interior of the island.  The run along the shore line had some small chop and some wakes from the boat traffic in the bay between the island and the mainline.  The board ran straight, and I had no problems with stability.  Once in the backwaters, I kept looking for debris to run the board over, but if you have ever been to Sanibel, they take keeping their island and waters clean to a very serious level.  Anyway, other than seeing a some manatee's with their babies, it was a quiet paddle.  However, the board ran straight.  My Velocitek Makai didn't really show any decrease in speed, and I didn't notice the fin.  The fin's front edge is squared, so I was thinking I might need to file it a bit and round it, but at least right off the bat, it didn't feel like a big fin like some of the others that I use from time to time.  On the way back out of the canal, we had a big boat come up and do an abrupt stop to allow smaller boaters behind us out, so it thru a really big swell into the narrow the canal.  We had to really ramp it up and punch out way out, and by then the wind had picked up, so the bay was choppier.  Again, no issue with getting pushed around or being unable to hold a line.  When we got back to the beach that we launched from, I caught a little wake and rode it to the sand.  I was standing on the tail, and the board just nose right up onto the beach with the fin folded up under.

The next day, we went into Tarpon Bay, which is a huge bay on the west side of the island.  A tropical storm was forming in the Gulf of Mexico and was heading our way.  In retrospect, we should have done a long, one way run with the wind but we were meeting some of the very few locals on Sanibel that paddle seriously, so we just did what they had already planned.  We had to cut across the mouth of the bay, taking the wind on our side and pushing across the white capped bay.  Shallow water in most spots.... only about 4 foot deep, so the wind driven white caps were only about a foot high, but they were also only a few feet apart, so it was relentless.  Wind was in the upper 20 mph's.  Again, the board held my line just fine.  Even went over a sand bar that my wife and one of our friends had to walk their boards over because of their fins catching.  For me, the board slid right over, but I had to "pole" across it with my paddle.  We then took some shelter between the some of the mangrove islands in the bay and worked our way in with a goal of coming out somewhere in the middle of the bay and to ride the wind back.  We finally found a spot, and did one last run into the wind, taking a angle to get into the center the bay before we turned and rode it home.  The fin did fine.  I could hold my line as best as i could with only the wind being the issue of how true I kept my line.  Once I turned and rode the wind back, the board ran like it always does with any other fin that I use.

I think this week I'll slap the fin onto my JP Australia Open Water Race 14x26.5 for a weekly fun race that the paddlers to in my area.  It's a three mile sprint with about 8 to 10 buoy turns that makes us go against current/ wind, with it, and across it.  I really only intend to use this fin for touring, but I'll run in the race just to see how it feels.  Besides, we do the race in our intra-coastal, so there's always some floating debris on the SE side of Florida.

My thoughts on the fin:  It could probably use the front edge rounded a bit to get the hard edges off of it.  The fin however, is no thicker than the Futures 10" weed fin that I pretty much use for everything on every board.

The fin attaches with two fin screws, and the spring mechanism is up in the fin box, with the rest of it outside.  One of the locals from Sanibel that has been making his own boards for years as well has building boats, liked the fin mechanism, but thought that it could be manufactured better/ stronger, and that it should have a bit of a flange to it to go against the board and cover up the fin box.

But so far, it has done what I was hoping for

[Weeble]

Here's a side by side with what I usually use

[deepmud]

So - it doesn't SUCK! Nice

It really helps to see it with your regular fin. I'm wondering about that spring in salt water, long term but worst case you get new ones occasionally maybe?

Duct tape over the slot? I think they can't make the fin cover it or it wouldn't work with various inflatables - and how much hydrodynamics do you need to worry about when there is that  slot portion sticking up with a fin in it?

Just having it not SUCK with a way to tip over rocks and bumps is pretty cool. I keep seeing the local lake with people taking inflatables out with no center fin so they can run the creek - I don't have the short side fins to compare but they LOOK like they SUCK at going straight.

A great option to have. I wonder why two screws?