8.5" Greenough 4A base dimension???

Discussion in 'Surfboards and Surfboard Design' started by clintopher, May 8, 2019.

  1. clintopher

    clintopher Well-Known Member

    79
    Jul 12, 2011
    Would someone mind taking a measurement on their 8.5 Greenough fin and letting me know what it is? I have a fin I'm reshaping for a mid length board and I want it to end up close to a Greenough 4A profile. I have a 10" to reference for overall shape and I've got the fin close to where I want it but the base is still too long.
     
  2. DawnPatrol321

    DawnPatrol321 Well-Known Member

    Mar 6, 2012
    I have a 9" Greenough 4A in my LB, that probably doesn't help you much though.
     

  3. clintopher

    clintopher Well-Known Member

    79
    Jul 12, 2011
    It might. I have a 10 in mine so I could try subtracting half of the difference between ours from yours to come up with a guess, i.e. 10" base - 9" base / 2 - 9" base. That should get me close.
     
  4. DawnPatrol321

    DawnPatrol321 Well-Known Member

    Mar 6, 2012
    I don't know if i'm doing this correctly but I measure 7 and 1/8" on the base of the fin itself. If I were to measure the longest part, which includes the extra piece that sticks out to hold the screw it's 7 and 13/16". Hope this helps.
     
  5. clintopher

    clintopher Well-Known Member

    79
    Jul 12, 2011
  6. DawnPatrol321

    DawnPatrol321 Well-Known Member

    Mar 6, 2012
    Anytime! Good luck.
     
  7. LBCrew

    LBCrew Well-Known Member

    Aug 12, 2009
    Find a high quality picture of the fin you want to replicate and scale it. You'll get a perfect match.
     
    DawnPatrol321 likes this.
  8. jaklsurfs

    jaklsurfs Well-Known Member

    501
    Apr 26, 2015
    if your close on the base dont sweat it too bad it will work , unless you butcher up the finish
     
  9. jaklsurfs

    jaklsurfs Well-Known Member

    501
    Apr 26, 2015
    I use pictures of the ones i want to make ,print them up and use them as a template, glue
    them to the material and cut them out on my bandsaw and clean up the profile
     
    antoine likes this.
  10. jaklsurfs

    jaklsurfs Well-Known Member

    501
    Apr 26, 2015
    Have some foam fins with carbon glass job on one of my older boards( my first epoxy) first thing you notice is the balance of the board ,the fins dont weigh much
     

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  11. clintopher

    clintopher Well-Known Member

    79
    Jul 12, 2011
    The original fin was a RFC El Gato. I reshaped it before this post using my 7" fcs flex fin and 10" greenough as french curves and it was a little too hard to turn but I left it pretty thick and the base was untouched. I reshaped it this weekend getting rid of some of the base and thinning out the fin a bit. We'll see how it works out next time in the water.

    Up next is a stab at making side bites. The purpose for even doing thins in the first place is I snapped one of the side fins. Being broke, I figured I'd turn the El Gato, a fin I never really liked in my LB, into a serviceable fin for the Stubby. Also, being broke yet having epoxy on hand, it hit me after I had another go at the fin that make a couple side fins from scratch couldn't be too difficult. I know I have some fiberglass somewhere. Putting my hands on it might prove challenging. But since I'm just experimenting anyway, I'm not opposed to making a micarta out of epoxy/fabric and shaping that.
     
    DawnPatrol321 likes this.
  12. LBCrew

    LBCrew Well-Known Member

    Aug 12, 2009
    That's the spirit, clinto... DIY!
     
  13. jaklsurfs

    jaklsurfs Well-Known Member

    501
    Apr 26, 2015
    Ive used a greenough fin as a template for a surfboard nose