Modifying thruster into a quad

Hi guys.  I have a 5’8 Hayden.  Its a fun board but i prefer quads.  I live in san diego and the waves tend to be a bit flat faced so quads have always helped me generate speed.  The plan is to buy some fcs plugs ( the orginal kind) and drop those in there.  I think it would look a lot more low profile than adding futures boxes, plus i dont have a set of futures quad fins.  Here’s a pic of the measurements of the thruster, can you please shoot me some suggested measurements for placement of the quad fins?  like how far up and out off the stringer do i place each end of the fin?  thanks!  i’ll document my steps for anyone who else with the balls to drill into a fresh Hayden. 

I referred to an old email from Hayden where i asked.  It was missing some details, but he said measure up 4 7/8" from the tail.  From there if i understand correct, measure from the stringer out to the rail, and then mark the mid point, which for me is 2 1/2" .   Then my quad fin is 4" long so i measure up another 4" and out 2 1/2".  I tested it on a few of my other boards, seems to be correct.  As always measure twice, thrice, or even more times cut once!!!  What do you guys think?

here’s the Greenlight fin placement diagram, and a couple others, hope it helps



Looks like those placements guides from Hayden are pretty close to the McKee multisystem. See here: http://www.mckeesurf.com/?page_id=267

You say your “prefer quads”, so would guess you have maybe one or two in your quiver. What do YOU like best? McKee type layout (i.e. rear fins closer to stringer) or the more “rail orientated” layouts like those in the pic’s posted by Huck?

Here’s a link to another layout guide: http://www.gearbox-surf.com/resources/PDF_Files/gb_quad_fin_layout_2014.pdf

As an aside, have you given any thought to:

a) the install process?

b) adding extra glass reinforcing?

c) any other ‘after glass’ fin systems?

 

 

 

Thanks for the feedback guys.  My quiver is pretty much anything but thrusters and they’re all such different shapes and sizes i dont really have much to compare with this Hayden.  However i will say i never met a quad i didnt like.  The closest thing i got is a 5’6 diamond tail Christenson, kinda like a dumpster diver, think he calls it the Kevin Bacon.  Its a good amount wider by about an inch in the tail.  Looking closer with the ruler,  Hayden basically recommended me to run the quads parallel to the stringer.  However looking at these resources and measuring all my quads shows the top part of the quad fin should be towed in by about 1/8".  So with that slight adjustment i think i got it.  

Hayden’s measurements put the quads a little closer together than Greenlight recommended.  Thats how Barca is running his quads, he said it keeps the thruster feel but more speed and better turns.   

http://surf.transworld.net/1000157233/photos/quivers-dustin-barca-2/

The plan is to get those single fcs plugs, drill a hole, mix up two part epoxy and some milled fiberglass and just drop them in there.  I can get the cant off the 5’6 with my bevel square.  

Others with more experience than me will have better knoweldge, but …

Keep in mind that when installing fin plugs, there is usually a “patch” of at least an extra layer of glass around the fin plug(s) … check the fcs install and note the “football shape” patchs they glass in when doing the laminate. I doubt your board will have any of those “patches” anywhere near where you are looking to add the new fin plugs. So, you may need to add some as part of your install process otherwise the strenth of your install could be compromised.

Hopefully some of the experienced crew will chime in …

 

Yeah good point about the fiberglass patches… Wouldnt hurt to add them.  Found this video from fiberglass hawaii doing the exact same thing im doing, this guy didnt make any patches though.  

 

https://www.youtube.com/watch?v=iumdWGx98Ig

Just looked at that video.

When installing X2 plugs you are supposed to join also to the underside of the deck (so called H pattern). Maybe the video installer could get away without this because he has additional strength from the centre stringer. Your board is EPS and without this your plugs will not be strong enough.

No need for  milled fibre for strength with Epoxy resin.

Would not recommend FCS plugs in this board construction. If this way your only option due to lack of tools,jigs etc at a bare minimum would put patches on bottom and do the H pattern. Would however suggest on getting a quad fin postion figured out very helpfull to have a fin system that allows some adjustment. Probox, surfinz,4wfs. EPS I think is better with under the glass boxes with flanges to distribute load.

If you are limited to fcs plugs suggest first installing higher density foam disks etc first. Got various low tech solutions depending what tools you have.

M

 

 

I don’t have any jigs which is why I’m going for the x2s although thr fusion plugs would be ideal. 

Depending on what other tools you have you could make a simple jig for Futures or FCS Fusion boxes. Then glass over. Is it worth it worth it unless you have a router and bits?,As an idea fcs developed the  fusion box and other under the glass boxes with flanges especially because of the softer EPS foam blanks. I honestly dont recommend the X2 plugs in your board. If it is absolutely the only way and for example you only had a hole saw as a tool you could find some higher density foam eg from old surfboard, cut a bigger disk from this and resin and glass into your board before doing a standard x2 plug install. Hate to put anyone off DIY but consider having Fusion etc put in properly to your prefered position. I think even Gearbox recommend high density inserts for light weight EPS as do 4wfs for their after glassing OTG box which is what I used a lot for adding extra fins to already glassed boards. Your board is unlikely to be super light weight EPS like that used for compsand cores for exampleso you will have to make a judgement on its strength for X2 plugs. but certainly  H pattern.

 

 

If i do this i definatly want to use x2’s.  i have a router so lack of tools isnt an issue.  I just think the fusion plugs would make the tail too heavy and mainly take up too much room on an already narrow tail.  Hmmm is it worth the risk??  i can do the H pattern, i have all the tools for  that.  You’d just pour straight 2 part epoxy in there, no milled fiberglass?

anyone ever try this??

GSI make a big thing of their EPS being high density and waterproof so that is true helps with the X2 plugs. I think you will find not much extra weight with fusion etc vs plugs and resin but sometimes plugs fit in the contours better. The Epoxy resin is plenty strong enough without milled fibre. I do 2 staged pour in case of exotherm for the resin depending on air temp. Hope someone can come in also with advice to help you make up your mind. Still think getting quads right can be tricky and aided massively if the box has some fin position adjustability even if only backwards and forwards…

Just an idea … what about a plug like this?

splug-sticker.jpg

http://www.shapers.com.au/categories/Surfboard-Fin-Systems/S%252dPLUG/

Has forward and backward adjustment … plus a larger “footprint” but does not have to be linked to the deck with the “H” pattern cut like FCS plugs …

???

 

the x2’s should do the job for quad rears, make sure you anchor to the deck. and do it in 2-3 pours with icepacks under the deck.

if you try and do it in 1 pour it will exotherm, and you’ll end up with a molten eps cave under your lam.

I’ve got a snapped 5’6" hypto in the shed. 5 fin setup

Rears are 4 7/8 from tail. 2 3/8" from rail, 2 5/8" from centreline. No toe in.

FWIW I have used a lot of s-plugs. They are very solid, but unless you do two cuts with the router they will definitely exotherm with the large volume of resin they hold.

X2s will be fine. I’ve done straightforward FCS epoxy installations without exotherm issues. I always score around the rim of glass after drilling with the flute of a drill to create a better bond. Even on thirsty eps I’ve not noticed leaking around plugs.

Thanks for keeping me motivated tej! Yeah i think x2s will work, they have all these little channels in them to absorb the epoxy. The boxes with a flange don’t have that so it’s give and take. The leash plug is holding solid in there and that’s basically an fcs plug. Even if they did fly out I could just drop in fusion plugs and that would hide the damage. Hayden said toe them in no more than 1/8 inch. Ok I’m pumped to do this again!