Think I really messed this one up! (0.1% catalyst not 1%)

Discussion in 'Fiberglass and Composite Boat Building' started by green1181, Aug 6, 2015.

  1. green1181
    Joined: Apr 2008
    Posts: 9
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Western Australia

    green1181 Junior Member

    So spent the day stripping the transom and stringers from the boat, cut 2 layers of 17mm ply for the transom and new stringers. Mixed up some polyester resin and cloth and sandwiched them between the 2 layers of ply.

    After I was finished I realized that I used 1ml to 1kg of resin! I have not clue what I was thinking...too many beers and too tired I guess.

    Since there is some catalyst added do you think it will eventually cure or should I rip it apart while its still wet (been just over 12 hours) and re-do the entire thing? Can I use the cloth that I have between the layers? Just the materials I used were almost $400 so I would like to salvage it if I can.

    thanks for the help!
     
  2. waikikin
    Joined: Jan 2006
    Posts: 2,365
    Likes: 130, Points: 73, Legacy Rep: 871
    Location: Australia

    waikikin Senior Member

    Well..... & I'm no where near being chemically qualified, I think you are going to have to wear this one. It may be "possible" to recylcle the under catlalysed material but not worth the concern.
    Just chuck & start again, treat as a learning experience & use the planning skills you've invested in to do better in the future:)

    All the best in your endeavours from Jeff
     
  3. TeddyDiver
    Joined: Dec 2007
    Posts: 2,579
    Likes: 123, Points: 73, Legacy Rep: 1650
    Location: Finland/Norway

    TeddyDiver Gollywobbler

    Set a warmer to heat the layup up to (now I don't remember excactly) about 70 C so it will kick.. Be aware not to burn everything!
     
  4. jorgepease
    Joined: Feb 2012
    Posts: 1,614
    Likes: 48, Points: 48, Legacy Rep: 75
    Location: Florida

    jorgepease Senior Member

    I wouldn't trust it
     
  5. SamSam
    Joined: Feb 2005
    Posts: 3,900
    Likes: 197, Points: 63, Legacy Rep: 971
    Location: Coastal Georgia

    SamSam Senior Member

    I would rip it apart, scrape the wood clean, wipe/scrub with acetone, and then scratch/roughen up the bonding surfaces all to hell with something like a nail or sharpened screwdriver or 16 grit bonded sandpaper (like a disc for a grinder). Vacuum off all the loose particles. I would then lay the wood out and coat the surfaces with catalyzed resin and let that sit for awhile so it soaks in, then re-coat and laminate/sandwich in 1 or two layers of 1 1/2 oz mat and clamp it up with clamps or removable screws.

    Mat is sold here by the oz per square foot, so 1 1/2 oz mat would weigh 13.5 oz per square yard.

    My first fiberglass work was with auto store polyester resin, used to stiffen up the body of a van. I totally under catalyzed it and it eventually hardened, but it took months of exposure to the air. Yours will probably never harden, not being exposed to the air.
     
  6. gonzo
    Joined: Aug 2002
    Posts: 14,980
    Likes: 822, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    A catalyst speeds up a chemical reaction. The reaction will happen without it, but take a lot more time. The problem with a very slow polymerization, is that the resin will start absorbing water and make a gooey mess (technical term). Heat will increase the reaction speed, so heat lamps may make it cure in a reasonable time.
     
  7. ondarvr
    Joined: Dec 2005
    Posts: 2,534
    Likes: 326, Points: 83, Legacy Rep: 506
    Location: Monroe WA

    ondarvr Senior Member

    You have a couple of issues going here.

    Resin will eventually become hard even without catalyst, but becoming hard and actually curing correctly are two very different things. Even if it became hard it would be weak and most likely fail.

    The other issue is using cloth and polyester resin for anything, the two don't work all that well together, the bond between the two pieces of wood would be poor even if it was catalyzed correctly.
     
    1 person likes this.
  8. TeddyDiver
    Joined: Dec 2007
    Posts: 2,579
    Likes: 123, Points: 73, Legacy Rep: 1650
    Location: Finland/Norway

    TeddyDiver Gollywobbler

    Jorgepease and Samsam, polyester resins are thermosetting resins. The catalyst starts the reaction which continues due excess heat as it's an exothermic reaction...
     
  9. SamSam
    Joined: Feb 2005
    Posts: 3,900
    Likes: 197, Points: 63, Legacy Rep: 971
    Location: Coastal Georgia

    SamSam Senior Member

    I was going to bring this up but I forgot.

    green1181, with polyester resin, normally use mat for the first layer against wood and also between layers of cloth or woven roving. Cloth and polyester doesn't stick too well to wood or cloth on cloth especially if the resin cures between laminating sessions. A lot of times you can peel it right off with a little effort.
     
  10. jorgepease
    Joined: Feb 2012
    Posts: 1,614
    Likes: 48, Points: 48, Legacy Rep: 75
    Location: Florida

    jorgepease Senior Member

    The other thing is I'v heard so many bad things about using polyester with wood.
     
  11. gonzo
    Joined: Aug 2002
    Posts: 14,980
    Likes: 822, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    There are all kinds of tales about that. However, millions of successful boats around the world prove them wrong.
     
  12. green1181
    Joined: Apr 2008
    Posts: 9
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Western Australia

    green1181 Junior Member

    Thanks for all the input. I checked last night and it is starting to get hard in places. I didn't know about the matt being better than cloth, I've just been reading forums and lots of people say to coat the stringers with 6oz cloth because it bends better.

    I did use some matting for the transom so I hope
    that will be ok, I also caught my mistake and used more catalyst
    when I soaked the matting sandwiched between the two layers.
    I am going on vacation for 5 weeks soon, hopefully we get some hot,
    dry weather and it doesn't make a gooey
     
  13. Milehog
    Joined: Aug 2006
    Posts: 396
    Likes: 26, Points: 28, Legacy Rep: 215
    Location: NW

    Milehog Clever Quip

    What's a decimal point between friends?
    We has a highway project where they were blasting a cliff next to a road to remove unstable rock.
    The engineer specified .5 pounds of dynamite per hole. The powder monkey read it as 5 pounds of dynamite per hole.
    The clean up took a few days.
     

  14. gregkuiper
    Joined: Jan 2015
    Posts: 69
    Likes: 1, Points: 8, Legacy Rep: 33
    Location: Irvine, CA

    gregkuiper Junior Member

    I had a similar issue and first attempted to put on a hot mixture of resin/catalyst thinking it would force it to cure. I then tried baking it in the sun and using a blow dryer. In the end I had to cut out the whole area out since the resin never cured.

    It sucks, but best to cut your losses now and fix.
     
Loading...
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.