SUP Sports Hammer: 4 Fin Versus 5 Fin for Surfing

[Night Wing]

Using more than one fin on a surf sup for flatwater is just going to create drag.

A single large center fin will track better and cut through the water more efficiently.

Drag or not, I have found while a single large fin will track better and cut through the water more efficiently in flat water, the single large fin does not turn a board more efficiently. The 5 fin setup on my board turns my board quicker on flat water than the single large fin depending on how I use my paddle when I want to make a sharp turn (90 degrees without sticking the nose of the board way up into the air as in a tight buoy turn) thereby when it comes to turning, the 5 fin setup gets the nod for efficiency (in my case) over the single large fin setup. In other words, I paddle leisurely on flat water so drag isn't my sole criteria because I'm in no hurry to get from Point A to Point B and back again to Point A.

This is why people should experiment with their boards to see what works and doesn't work for them because there will always be trade offs in conjunction with how a sup board is/was designed by it's shaper.

[Badger]

Night Wing, how much total flatwater time have you put on the Hammer so far? It takes most beginners at least 40 or 50 hours to develop a paddling technique and really learn how how a board behaves.

You should be able to turn that board 90 or even 180 degrees standing flat on the board with just one stroke of the paddle, regardless of how many fins it has. The board doesn't carry enough speed on flatwater for the side fins to help it through a turn.

The side fins are angled and canted to help it turn in a planing situation while on rail when surfing. They do nothing when the board is being paddled. The fact that the fins are not pointed straight ahead is what causes the drag when going slow. It becomes less of an issue when the board is on plane.

The nubster does not make it a five fin. It's too small to be considered a fin. A true five fin would have a center fin similar in size to the other four. The nubster is meant to slightly enhance the turning ability of a quad in a surfing/planing situation. It doesn't have enough area to to have any measurable affect on flatwater paddling.

I think you are jumping to your conclusions a bit too soon. It takes a lot of experience for someone to just go out on a board and say this or that doesn't work.

The great thing about this forum and the internet is that you can research how things work and study technique. There are many tried and true ways to do things. It's not all personal preference.




 

[addapost]

Seems like an awful lot of fin to me, regardless of the board or the conditions (surf or flat). But if you think it works for you, have fun, that's really what it is about.

[Night Wing]

#Badger

Looking at my paddling log book, I've got about 27 hours of paddling on flat water with my 8'11" Hammer. Yes, I know I don't have a lot of riding hours on my Hammer and I'm well aware of that, but I'm letting my Hammer "speak to me" and I'm listening to her. I could be jumping to conclusions, but my paddling technique is still evolving at this point.

With my 12'2" Hobie, which I bought last November of 2015, my log book shows I've got around 132 hours on flat water. Turning my Hobie on flat water is a "pita" especially if it's on a nice glide with some speed. I want to turn the Hobie, but the Hobie wants to keep tracking in the direction I was heading so it wants to turn sideways like in a skid. I think you would refer my skid to being skatey. So I'm comparing my quad + 1 Hammer against my single fin Hobie from a dead stop and also when I'm gliding.

You forget I come from a 12 year kayak background so I'm using some of my kayak paddling techniques to compensate for the canted side fins which produce drag when I'm riding my Hammer. My old Ocean Kayak SPTW was 14'9" long, 26" wide and weighed 55 pounds (empty = no gear). When I bought my SPTW, everyone in the kayak community said it was too long to make a 180 degree turn, from a dead stop, in 3 paddle strokes. Yet, by experimenting with my paddle stroke, I was able to make a 180 degree turn, from a dead stop, with ease with 3 paddle strokes, 2 on one side, 1 on the opposite side. Some of my friends who had  shorter lengthTarpon 140's (14' long, 28" wide and weighing 65 pounds, it always took them 4 paddle strokes (sometimes 5) to make a 180 degree turn from a dead stop. I tried my paddling technique on their 140's and I could turn their 140's in 3 paddle strokes. As they say, "different strokes for different folks".

As for my nubster fin, it's probably due to my paddling technique (good or bad right now depending on one's view), I've found I can tell the difference when making a 90 degree turn with the 4 fin compared against the 5 fin (for argument's sake since you don't consider a nubster fin to be a 5 fin and I can and will accept that) from a dead stop. I think the design of the Hammer underneath and it's rocker has something to do with it, but I'm no engineer. Just a guess on my part.

Anyhow, what works for me may not work for someone else, but it behooves someone with any type of board not meant for flat water (like a short surf sup which my Hammer was designed for) to experiment and think outside of the box if they want to see how well (or not) a short surf sup will perform on flat water which their short surf sup isn't designed for.

On a side note, since I do mostly flat water cruising because I've got some nice private lakes near me where I have access to and a large public 20,000 surface acre lake 25 minutes from my home, I wish I could get my hands on a Starboard Converse 9'x30" and a King's Super Simmons 9'x30" to demo test ride them and compare them against my Hammer 8'11"x31 since all of them are quad + 1 fin configurations.

As "Addapost" said in his comments, I'm having fun and that is what counts in the end.

[Zooport]

I think fin size, number and configuration is a matter of personal taste.  If you like the way it handles, then you made the right choice.  Your tastes will continually change, so go with it and have fun. 

[Badger]

That's the way I am too. Constantly changing and progressing. A lot of my enjoyment comes from the never ending progression. I've been through nine boards in three years learning about volume, the dynamics of board shape, the effect of fins, paddle length and technique, etc and I still have a long way to go. The fun doesn't end when I leave the water.

Just to clarify one more time. A quad with a nubster is still a quad. It's not a five fin or a quad+1 or a 4+1.

+1 indicates a center fin that is larger than all the other fins.

With a five fin set up, all the fins are approximately the the same size.

The board has a five fin configuration, meaning that it has five fin boxes.

The nubster is so tiny that it doesn't need to be added to the description. The title of this thread should really be "SUP Sports Hammer: Surfing with or without a nubster".

[PonoBill]

I have a theory, based on nothing more than mental models and a little bit of experimenting, that a tiny central fin between twin fins acts as a fence to block interference between the fins. I picture the pressure waves from the fins angling inward, hitting the nub and reflecting back towards the rail instead of interfering with each other. It's probably bullshit, but it's consistent with the way the wake behind the board looks: Just a roiled surface instead of the braided look with twin fins alone and a deep divot (draftable) with a single fin. I did a few videos. Should have saved them, but as soon as I have my blackfish somewhere warm again I'll do more. Maybe not relevant to sufboards since asymmetric foils for quads generally point outwards (LA twin fin foils point inward) and the rear fins of Controller-style quads are symmetric, but there still should be pressure waves moving between them.

A tiny nub fin between my LA dual fins makes a big change in the speed I can maintain--I think there is less drag with the added fin than without it--very much a counterintuitive result. It's not a small difference, it's more than ten percent.  I haven't been able to come up with any good reason for that--this is the best idea I've got other than I'm just deluded. It could well be that a 4 plus nub fin setup would yield comparable substantial and unexpected changes to the performance of a board.

I'm going to try just a fence--not a foiled fin, just a low aluminum fin. Might be better, might be nonsense. I think what goes on with multiple fins would need a supercomputer to really model.

[Night Wing]

That's the way I am too. Constantly changing and progressing. A lot of my enjoyment comes from the never ending progression. I've been through nine boards in three years learning about volume, the dynamics of board shape, the effect of fins, paddle length and technique, etc and I still have a long way to go. The fun doesn't end when I leave the water.

Just to clarify one more time. A quad with a nubster is still a quad. It's not a five fin or a quad+1 or a 4+1.

+1 indicates a center fin that is larger than all the other fins.

With a five fin set up, all the fins are approximately the the same size.

The board has a five fin configuration, meaning that it has five fin boxes.

The nubster is so tiny that it doesn't need to be added to the description. The title of this thread should really be "SUP Sports Hammer: Surfing with or without a nubster".

If the description needs to be changed, I would. However, there is no way for me to edit the title since this system doesn't allow me to after a certain amount of time and that time has passed. If a moderator can change the title to, "Surfing with or without a nubster" (without the quote marks), then by all means edit the title to make the change.

[RATbeachrider]

I tested the knubster on the 8'3x29 Sidewinder with 19" wide tail and the board was like a log on a hard bottom turn.  Too wide of a tail, not enough concave and no vee.  Awesome board as a quad.

[Badger]

That's the way I am too. Constantly changing and progressing. A lot of my enjoyment comes from the never ending progression. I've been through nine boards in three years learning about volume, the dynamics of board shape, the effect of fins, paddle length and technique, etc and I still have a long way to go. The fun doesn't end when I leave the water.

Just to clarify one more time. A quad with a nubster is still a quad. It's not a five fin or a quad+1 or a 4+1.

+1 indicates a center fin that is larger than all the other fins.

With a five fin set up, all the fins are approximately the the same size.

The board has a five fin configuration, meaning that it has five fin boxes.

The nubster is so tiny that it doesn't need to be added to the description. The title of this thread should really be "SUP Sports Hammer: Surfing with or without a nubster".

If the description needs to be changed, I would. However, there is no way for me to edit the title since this system doesn't allow me to after a certain amount of time and that time has passed. If a moderator can change the title to, "Surfing with or without a nubster" (without the quote marks), then by all means edit the title to make the change.

I meant the nubster doesn't need to be added to the description of the fin set up, not the title of the thread. With or without a nubster, it's still just a quad.

[PonoBill]

Can be done at any time. And it shows up in the recent posts with the new title. Always handy for making a point.

[Badger]

Yes but it only does it for that particular post that you are writing. I don't use recent posts. I open the site with unread posts and click the orange "New". The new title doesn't appear until I read the post and it's easy to miss.

I prefer unread posts because I like to see the new posts of a thread in the order that they were written. With recent posts everything is all mixed up and in a backwards order.

[SUP Sports ®]

#Badger

Looking at my paddling log book, I've got about 27 hours of paddling on flat water with my 8'11" Hammer. Yes, I know I don't have a lot of riding hours on my Hammer and I'm well aware of that, but I'm letting my Hammer "speak to me" and I'm listening to her. I could be jumping to conclusions, but my paddling technique is still evolving at this point.

With my 12'2" Hobie, which I bought last November of 2015, my log book shows I've got around 132 hours on flat water. Turning my Hobie on flat water is a "pita" especially if it's on a nice glide with some speed. I want to turn the Hobie, but the Hobie wants to keep tracking in the direction I was heading so it wants to turn sideways like in a skid. I think you would refer my skid to being skatey. So I'm comparing my quad + 1 Hammer against my single fin Hobie from a dead stop and also when I'm gliding.

You forget I come from a 12 year kayak background so I'm using some of my kayak paddling techniques to compensate for the canted side fins which produce drag when I'm riding my Hammer. My old Ocean Kayak SPTW was 14'9" long, 26" wide and weighed 55 pounds (empty = no gear). When I bought my SPTW, everyone in the kayak community said it was too long to make a 180 degree turn, from a dead stop, in 3 paddle strokes. Yet, by experimenting with my paddle stroke, I was able to make a 180 degree turn, from a dead stop, with ease with 3 paddle strokes, 2 on one side, 1 on the opposite side. Some of my friends who had  shorter lengthTarpon 140's (14' long, 28" wide and weighing 65 pounds, it always took them 4 paddle strokes (sometimes 5) to make a 180 degree turn from a dead stop. I tried my paddling technique on their 140's and I could turn their 140's in 3 paddle strokes. As they say, "different strokes for different folks".

As for my nubster fin, it's probably due to my paddling technique (good or bad right now depending on one's view), I've found I can tell the difference when making a 90 degree turn with the 4 fin compared against the 5 fin (for argument's sake since you don't consider a nubster fin to be a 5 fin and I can and will accept that) from a dead stop. I think the design of the Hammer underneath and it's rocker has something to do with it, but I'm no engineer. Just a guess on my part.

Anyhow, what works for me may not work for someone else, but it behooves someone with any type of board not meant for flat water (like a short surf sup which my Hammer was designed for) to experiment and think outside of the box if they want to see how well (or not) a short surf sup will perform on flat water which their short surf sup isn't designed for.

On a side note, since I do mostly flat water cruising because I've got some nice private lakes near me where I have access to and a large public 20,000 surface acre lake 25 minutes from my home, I wish I could get my hands on a Starboard Converse 9'x30" and a King's Super Simmons 9'x30" to demo test ride them and compare them against my Hammer 8'11"x31 since all of them are quad + 1 fin configurations.

As "Addapost" said in his comments, I'm having fun and that is what counts in the end.

There definitely is a difference in lateral resistance, drive, and drift that can be felt and experienced when using my StubNubs shown in bottom image (2.25" / 4.34 in2 or 3.19" / 7.84 in2)...you can also feel the difference when they are moved fore and aft in the box...

Wide tailed quads generally will almost all gain more drive and transition from rail to rail smoother, with the addition of a nubster in the center box...especially, with my board designs that incorporate lots of Vee and belly spline into the tail...if you use a smaller one and move all the way back in the box it will have minimal addition of drag but, reward you with a little bit more drive off of the bottom on bigger days...on smaller days most boards will be a little bit looser without one...but, there really isn't much downside to not using one...

There are also 5 fin box boards on the market where adding the forward quad sidebiter boxes was almost an afterthought because the designer doesn't believe in it...or, have experience with it...;-)

Additionally, I've seen the 5 boxes clustered so close together that there is no way a quad + nubster would work well...too stiff...etc...

http://supsports.com/sup-fins

[Night Wing]

@WarDog

My fin configuration looks exactly like the seafoam green Hammer (with the black exposed carbon black rails) in your series of photos) for my 5 fin placement. My nubster is at the back of the 10" fin box (toward the tail) as in the same photo.