Buccaneer 24 Builders Forum

Discussion in 'Multihulls' started by oldsailor7, Jul 22, 2009.

  1. freddyj
    Joined: Oct 2013
    Posts: 287
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    Location: kansas

    freddyj Senior Member

    I ordered the wood from Homestead Hardwoods. I was very pleased with the service from them and the delivery time was shorter than expected. As far as the quality of the wood, I have nothing to compare to since I've never seen marine plywood before.
     
  2. freddyj
    Joined: Oct 2013
    Posts: 287
    Likes: 23, Points: 18, Legacy Rep: 37
    Location: kansas

    freddyj Senior Member

    I am having a very hard time telling if I am dealing with amine blush or not-fully cured epoxy. If I let it cure 24 hours it gums up my sandpaper when I sand it. So I tried wiping with a damp rag first and then sanding, it still gums up the paper. What am I doing wrong? How does one tell the difference?
     
  3. Corley
    Joined: Oct 2009
    Posts: 3,781
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    Location: Melbourne, Australia

    Corley epoxy coated

    Sounds like your epoxy hasn't fully cured it will go rock hard when it is. I like to set a heater up nearby for a good cure if it's cold.
     
  4. freddyj
    Joined: Oct 2013
    Posts: 287
    Likes: 23, Points: 18, Legacy Rep: 37
    Location: kansas

    freddyj Senior Member

    So how do you tell the difference between blush and uncured?
     
  5. Corley
    Joined: Oct 2009
    Posts: 3,781
    Likes: 196, Points: 63, Legacy Rep: 826
    Location: Melbourne, Australia

    Corley epoxy coated

  6. oldsailor7
    Joined: May 2008
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    Location: Sydney Australia

    oldsailor7 Senior Member

    You have not-fully cured epoxy. Amine blush is something quite different.
    This usually occurs if the ratio of hardener to resin is not exactly correct.
    What brand of epoxy are you using. :?:
     
  7. freddyj
    Joined: Oct 2013
    Posts: 287
    Likes: 23, Points: 18, Legacy Rep: 37
    Location: kansas

    freddyj Senior Member

    I am using Axson epoxy. So, amine blush is different looking?
    If the epoxy is still tacky after 24 hours, does that mean I can recoat it without sanding at this point?
     
  8. 2far2drive
    Joined: Nov 2011
    Posts: 116
    Likes: 11, Points: 0, Legacy Rep: 82
    Location: Houston, TX

    2far2drive Senior Member

    like OS said, sounds uncured. I know you are in norcal right? The temperature for epoxy work is very important. I used to blow it off like I do everything and I lost batches several times. Now I have a digital thermometer and humidity deal in my garage. You need appropriate hardener for the temps you are working in, including overnight.

    I used all west (I get a good deal on it) and it blushes. I noticed my blush when humidity was high during cure (Houston Texas, no surprise there). The blush on west appeared yellowish and sometimes cloudy, mostly yellow though.

    when fully cured, get an SOS pad and warm/hot water with dish soap. If the yellow / white cloudy stuff washes off, then its amine blush.

    no amount of sanding worked until I washed it. Came right off.
     
  9. 2far2drive
    Joined: Nov 2011
    Posts: 116
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    Location: Houston, TX

    2far2drive Senior Member

    Ahh Kansas. Is your workspace heated??? West with 209 fast hardener refuses to cure lower than about 48f. Even at 50f it can take 2 days. Get some heat lamps if you don't have any already. Building in the winter can be rough if you don't have a heated workshop. I dont... So most of my building stops for now.

    I've paid the price for ignoring temps. Just saying from a professional "ahh I'm sure I can swing by" type person, when they say 48f or whatever, THEY MEAN IT! hahaha. Good luck and get back to us.
     
  10. freddyj
    Joined: Oct 2013
    Posts: 287
    Likes: 23, Points: 18, Legacy Rep: 37
    Location: kansas

    freddyj Senior Member

    Thanks for the great info. Yes, I'm in Kansas. It's a heated shop. When I'm out there I run it up to 70 or so cause I like to work in a t-shirt and I hate cold hands. But, when I close up for the night I turn the heater down and since the shop is well insulated, it only gets down to 55 overnight. But, the parts may be on the concrete floor which stays cooler. At least this time of year the air is real dry. The epoxy stays clear, so from what I gather it is probably not blushing, but not cured all the way.
    So, at this point could I just recoat, or should I wait a few days and then sand it first?
     
  11. bregalad
    Joined: Dec 2010
    Posts: 113
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    Location: Georgia

    bregalad Senior Member

    I think you should wait until either it fully cures, or you figure out what else is causing the problem. If there is some persistent issue you don't want to add more goo.
    Temperature and slow cure may well be the problem. Heat and time will fix that.

    How did you measure the ratios, by weight or volume, and how accurately?

    Is all of it in the same state or did some areas fully cure? If some areas cured and some didn't you probably have mixing issues.

    Do a small test patch (say 1 sq. ft.) measuring and mixing precisely and controlling temp. for say 24 hrs. If that doesn't cure you need to find out why.

    Edited:
    Which Axson epoxy are you using? Personally I wouldn't choose any on this page http://www.axson-na.com/axna-con-epoxy.html in lieu of more proven epoxies for composite construction. I've had good results with West, System Three, and with Marinepoxy from Duckworks.
     
  12. freddyj
    Joined: Oct 2013
    Posts: 287
    Likes: 23, Points: 18, Legacy Rep: 37
    Location: kansas

    freddyj Senior Member

    There's not really a problem. I just wanted to get some feedback so I could make more efficient use of time. I'm using Axson 2108 laminating resin. I am weighing it accurately when I mix. It eventually gets rock hard, but takes more than 24 hours. My dilemma is: when it is appropriate to recoat without sanding and how to tell if its blush I'm seeing. After 24 hours in my cool (not cold) shop, the surface is almost as sticky as masking tape. It's colorless so it must not be a blush. If I could recoat without sanding at this point I could get a lot more production done quicker. I only have 2 or so hours an evening to work on it, so it would be nice to come in the next evening and just start recoating. Otherwise I have to wait two or three days so I can sand without excessively gumming up lots of expensive sandpaper.
     
  13. outside the box

    outside the box Previous Member

    Freddyj
    Is this what you are using?
    http://www.axson-na.com/TDSs/TDS - AL 2108 US Rev 02.pdf
    If so it might seem that your issue if cracking off over time beyond 24hr is heat related, the attached sheet suggests your pot life 20-30min ( 1pound at 77degf) with demold of 8-12 hours so yours curing beyond 24hrs
    would suggest low temp in your curing enviroment (as long as you have total cure with no soft spots, soft spots imply a mixing error)
    It will have blush Of some sort (even the low blush systems do) and the guys before have rightly mentioned a warm water suds wash, we wipe off then we esol wipe (ESOL is a hydrocarbon solvent blend specifically designed for the cleaning up of Epoxy systems). I wouldn't recote without abraiding after the blush being removed, only time I would recote without the above is when using peel ply.
    What made you go with the 2108?
    Was this given as an option by your supplier?
    http://www.axson-na.com/TDSs/TDS - AL 2103-2103LPL US Rev 01.pdf


    Regards
    Craig and the Ezifold Team



    QUOTE=freddyj;723673]There's not really a problem. I just wanted to get some feedback so I could make more efficient use of time. I'm using Axson 2108 laminating resin. I am weighing it accurately when I mix. It eventually gets rock hard, but takes more than 24 hours. My dilemma is: when it is appropriate to recoat without sanding and how to tell if its blush I'm seeing. After 24 hours in my cool (not cold) shop, the surface is almost as sticky as masking tape. It's colorless so it must not be a blush. If I could recoat without sanding at this point I could get a lot more production done quicker. I only have 2 or so hours an evening to work on it, so it would be nice to come in the next evening and just start recoating. Otherwise I have to wait two or three days so I can sand without excessively gumming up lots of expensive sandpaper.[/QUOTE]
     
  14. freddyj
    Joined: Oct 2013
    Posts: 287
    Likes: 23, Points: 18, Legacy Rep: 37
    Location: kansas

    freddyj Senior Member

    I have used the 2103 before. It is a white version of the 2108. I wanted a clear epoxy for some reason.
     

  15. bruceb
    Joined: Nov 2008
    Posts: 1,275
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    Location: atlanta,ga

    bruceb Senior Member

    Take a day off

    Do some tests. Keep a temp/time record of every batch you mix. If you set up a graph sheet, it only takes a moment to write it down. Always make a couple of small test samples with scrap wood, and keep one in the shop until it sets, and take the other one somewhere that stays above 70 degrees and compare them every 4 hours.
    If you don't get control of your epoxy system, you are going to mess up!
    I realize you are sort of forced to use the Axson system, but from reading the product info, it seems like a system more suited for production type settings where temps are closely controlled. I am sure it will work, but you might have to adjust your work area to its needs.
    As an example, I have five different catalysts and three different resins for the system I use, which allows a much wider practical working performance. I just got a good (overnight) cure in 45 degree weather without having to add heat.
    B
     
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