Saturday, 2 May 2009

DIY - Fins

There are many reasons why you may want to mould your own fins - you may want to save money, to make a shorter copy of a favourite fin or improve the performance of a fin in certain conditions.

I chose to make my own fins when I copied a Flow 66 back in 1998. It came with both an upright and swept fin and I wanted the same versatility so I copied them using a quick method that only took a few hours. I also wanted to use a Tuttle Box instead of the Power Box that was used on the mistral, so I also had to cast a new head. I also fabricated my own fin box which is still going strong today.

I will break down each of these steps into their own DIY articles as follows:

  • DIY – Fins – 1 Step Lay-up Process

  • DIY – Fins – 2 Step Lay-up Process

  • DIY – Fins – Making a fin Mould – Quick Mould

  • DIY – Fins – Making a fin Mould – Production Mould

  • DIY – Fins – Making a Fin Base Mould

  • DIY – Fins – Moulding a Fin Base

  • DIY – Fins – Making a Fin Box Mould

  • DIY – Fins – Making a Fin Box

  • DIY – Fins – Designing & Making a Fin Plug (original)

  • DIY – Fins – Making a G10 Fin

  • DIY – Fins – Making a Fin Copying Machine (pantograph)

I hope to do these articles in the coming weeks(& months!), watch this space.


  1. Promise to follow each & each update.
    Am familiar with comp'-materials tec but have no experiance.
    Thanking u in advance for the great info, if no objection will update my local comunity on our forum (1060 signed users)?

  2. No worries Ofer, the more the better!

  3. Tim,
    Looking forward to your DIY fin articles.
    Very informative site
    Regards Arnold

  4. Thanks Arnold, shouldn't be too far off getting some info on to the site.

  5. Hi Tim,

    Any idea when you will be making this series of articles?

  6. Hi Robert,
    I have out of action for a while and am planning on making a few fins soon, this will allow me to get good photos and break down the process. Which in particular are you interested in - machining G10 or Moulded Carbon?
    Regards, Tim.

  7. Hi Tim,

    I'm interested in Moulded Carbon. I have a good idea on how to make a mould. But have no Idea how the lay-up is made, cutting the Carbon and glass, putting the filler in the middle and drying. Are they Pressed together?

    greetings Robert

  8. Hi Robert,
    The layup can be 1 step or 2 step.
    In the 1 step you layup both sides of the mould and butter them up with minimal filler and then clamp the mould halves together.
    In the 2 step you layup both sides and allow them to cure or vacuum bag them individually for maximum carbon to resin ratio. You then bond the cured halves together by buttering the halves and clamping the mould shut. Both have their pro's and cons which can be weighed up depending on the type of fin being produced.

    I have 2 fins I want to mould shortly and so I will do this article soon.
    Regards, Tim.