Quad convertables

[Slowman]

With the release of the FCS's TC aqualine tri-quad fin set it looks like there is an intention to have boards that can be ridden as either a quad or thruster set up.

From a little research on the net, I see Reidel and a few others are saying normal thruster shapes work well as quads too and the innovation for quads is mostly in the fin placement. On Reidel's website he even has quad pintails and guns which look a bit ugly bt if they work what the hell.

How hard is it to add the extra FCS plugs after construction to make a "convertable" from your thruster. If it works I see this as adding some versatility to a board.

[ric_vidal]

How hard is it to add the extra FCS plugs after construction to make a "convertable" from your thruster. If it works I see this as adding some versatility to a board.

Adding plugs isn’t a huge concern, your local ding fixer could probably do that. I don’t know that an individual can readily get their hands on FCS plugs or have the necessary tool attachments/jigs, not that it is rocket science.

I’m not buying into the placement and all that do-dah.

Always whack in a couple of short fin boxes as an alternative, BUT that has other considerations.

[Natho]

The best Quads are designed specificaly for a Quad set up, rather than a board designed as a thruster with an extra plug here and there.

So setting up a thruster as a Quad will more times than not = a dog Quad.

I don't have enough time right now to go into all the reasons why.

[Slowman]

...
So setting up a thruster as a Quad will more times than not = a dog Quad.
...

So it might work with some? Any examples that might work rather than go into details?

[longbum]

...
So setting up a thruster as a Quad will more times than not = a dog Quad.
...

So it might work with some? Any examples that might work rather than go into details?

I'd say this is THE fad, converting your boards into something else. Can a thruster be converted to a single fin of twinny and have the same feels as an original one of those......?
answer = NO.

[kreepykrawly]

When they first came out years ago we used to call them Thrashers. I wonder if anyone else called them that.

[Slowman]

...
So setting up a thruster as a Quad will more times than not = a dog Quad.
...

So it might work with some? Any examples that might work rather than go into details?

I'd say this is THE fad, converting your boards into something else. Can a thruster be converted to a single fin of twinny and have the same feels as an original one of those......?
answer = NO.

Notwithstanding the original heading of this thread, I am not talking about a conversion, I am talking about a convertable. That is, a board that can be changed between a thruster and a quad.

Like I said with FCS's tri-quad sets there seems to be some intention. I don't expect it to be feasible with all plan shapes but with boards with some area in the tail like swallow tails and semi-fishes I thought it might be feasible. To my untrained eye some of the semi-fish designs in quads look the same as some thrusters.

Just exploring the options and feasibility is all I want to do.

Looks like McKee multisystem is one attempt

[jfdi]

Sounds to me the answer lies in whether the front side fins for 4 fin setup are positioned in the exactly the same place as you would a thruster. According to what Longbum is eluding to, to get optimum benefit in performance with 4 fins (and check out his photo on his quad in photos post - what a shot !), the answer is no.

Putting 5 fins in is being done, but major performance differences in aspect of a boards deisgn can be achieved with just slight differences in dimensions by cm's, so Longbums' comments make good sense to me.

Check out this and you switch between thruster and quad in the graphic and instantly see the placement difference :

http://www.surfingguide.org/boardspecs/fins.aspx#quad

[longbum]

^^^exactly !
In a quad set up the front fins and back fins are positioned more forward. So if you go for a 5 plug setup with the option to change between a quad and thruster, well ya gonna have a board that goes well as a thruster but pretty shitty as a quad or vice versa, so why bother ??
My opinion is that these guys are trying to take the shortcut and just jumping on the latest trend bandwagon. Waste of time really.
Do yourself a favour and just go either way, thruster or quad.

[Slowman]

^^^exactly !
In a quad set up the front fins and back fins are positioned more forward. So if you go for a 5 plug setup with the option to change between a quad and thruster, well ya gonna have a board that goes well as a thruster but pretty shitty as a quad or vice versa, so why bother ??
.

Agreed but what could make it work is a special set of quad front fins with offset tabs to push the front fins forward of the thruster set up.
So you have regular side fins for thruster - offset tabs for quad
But what about fin proximity to the rail? Thats different between thruster and quad.To vary that your looking at a double plug with two parralel slots!
My head hurts

That would be interesting. I have both a thruster and quad in Sydney (6 boards actually) but I'm currently on an island just off the Philipine Sea south of Japan (plenty of typhoon activity this summer) and only have one board, which I leave here. After riding my new quad it seemed if 2 extra plugs would be all it took to make my afterburner 2 boards in 1, the versatility it would deliver would be worthwhile. This place is no surf destination but gets pretty good waves sometimes however it is good to have a versatile board to cover a wide range of conditions. I also have a mountain bike I keep here, I don't think it would be "polite" to bring the whole quiver, if you know what I mean .

[Slowman]

Noooooooooooooo!

Sorry, yes it's true typhoon Sepat is going to churn up some big seas.

[SharkBoy]

interesting post

I just got a quad, it is 5'11" x 18 5/8" x 2 1/4" single concave, I have had alot of fun and hell trying to figure it out with different fin set ups and such.

The fin positioning is as follows:

Front fins, 11/4" up and toed in about 1/4" based on a 4.5" fin, 1-1 1/8" off the rail

Back fins 5.5" up, 1 1/2" inches off the rail, toed in the same.

I am no shaper but it does seem to me that the front fin positions are pretty similar to my grovel type shortboards. (I have had several types and have noticed that the front fins are usually at this same position)

I am considering putting in two plugs in the tail to try it out as a thruster, in fact, I am wondering if the shapers made a bit of a mistake because I thought quads were supposed to have less toe-in then thrusters.


does surfing a board with extra plugs sacrifice to any serious degree the performance?

[bombora]

A convertable board that DOES work _ though it's not a quad _ is the MR twins in various configurations. Trailer fin taken out, a la today's gutless "waves" and you get classic twinnie speed out of nothing and looseness; trailer back in and I've had a ball in OH conditions when the waves aren't too evil (that's when the thruster comes out).