Epoxy pot life—Is there a formula based on amount of epoxy?

Discussion in 'Fiberglass and Composite Boat Building' started by ahender, Apr 1, 2023.

  1. ahender
    Joined: Jan 2009
    Posts: 91
    Likes: 4, Points: 8, Legacy Rep: 10
    Location: Athens, GA USA

    ahender Junior Member

    If 3 ozs of epoxy has a pot life of 60 minutes, is there a way to determine pot life for larger quantities, with temperature and container shape being constant? Also, for each 18 degree F temperature increase, gel time is reduced in half. How does this temp increase affect viscosity percentage? Thanks.
     
  2. jehardiman
    Joined: Aug 2004
    Posts: 3,823
    Likes: 1,204, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Depends too much on the shape of the "pot". Avoid shapes that concentrate the mass (Yes, it is possible to set epoxy on fire through catalyzation heat!) Wide shallow pans give the longest pot life for pre-coating. But really you should consider pre-preg and/or infusion if you need that much.
     
    fallguy likes this.
  3. fallguy
    Joined: Dec 2016
    Posts: 7,769
    Likes: 1,727, Points: 123, Legacy Rep: 10
    Location: usa

    fallguy Senior Member

    I won't give you any absolutes.

    If you keep epoxy below 72F; the viscosity increases and around 60F becomes unworkable and drives higher content when worked for each degree.

    If you drive epoxy above about 85F; the stuff does thin, but will kick quite easily.

    The in between 72-80F is sort of the magic between workability and being thin enough to flow.

    I always try to work the stuff between about 65-75 degrees; then sometimes increase ambient after the work to drive the cure.

    I don't have anything other than experience, but below 72 and the epoxy I used went up in percentage in final product, so I always stored it up off the floor and heated the shop to 72F.

    Your 18 degree question is outside my comfort.

    One time, I heated epoxy over a water bath for neat coating, but maybe only 4-5 yards at 2 oz.
     
    Last edited: Apr 1, 2023

  4. ahender
    Joined: Jan 2009
    Posts: 91
    Likes: 4, Points: 8, Legacy Rep: 10
    Location: Athens, GA USA

    ahender Junior Member

    Thank you both for replying.
     
    fallguy likes this.
Loading...
Similar Threads
  1. andysailor
    Replies:
    4
    Views:
    4,026
  2. Space
    Replies:
    129
    Views:
    4,925
  3. mrdebian
    Replies:
    11
    Views:
    790
  4. abosely
    Replies:
    8
    Views:
    1,339
  5. abosely
    Replies:
    4
    Views:
    853
  6. leaky
    Replies:
    19
    Views:
    2,252
  7. abosely
    Replies:
    6
    Views:
    959
  8. Klink Sanford
    Replies:
    29
    Views:
    2,928
  9. ajse
    Replies:
    2
    Views:
    958
  10. Robert Biegler
    Replies:
    6
    Views:
    1,915
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.