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System Three epoxy

Discussion in 'Strippers, Stitch-n-Glue, and Other Wood Composite' started by tuckerman, Sep 26, 2013.

  1. tuckerman

    tuckerman Curious about Wooden Canoes

  2. Dan Miller

    Dan Miller cranky canoeist Staff Member

    According to the System Three website, 5 Minute QuickCure is not waterproof, only water resistant. Typically, 5 minute epoxies have significantly less bonding strength than slower curing resins. You should call System Three and discuss your intended use with them.

    If you compare apples, the 5 minute epoxy is much more expensive at $220/gallon kit, where S3 general purpose resin is about $120/gallon kit and West System at $140/gallon kit.

    I've only used West System for larger epoxying projects. I do use Quick Cure and S3 T-88, but only in certain situations.
     
  3. Greg Nolan

    Greg Nolan enthusiast

    I generally have some of the System Three 5 minute epoxy on hand as a general use glue for small tasks, when I want a quick cure. I have found quite satisfactory, generally measuring the 1:1 ratio by eye, squeezing out blobs onto a scrap piece of cardboard and mixing with a stirring stick It is fairly thick -- I have never felt the need to use any additive. It is described as highly water resistant, but not water proof -- this would be sufficient, I think, for repairing stems, at least the upper part of stems not usually submerged. I don't know that I would use it where extremely long periods of submersion are expected. I have not had any problems using this stuff.

    I also generally have some System Three T-88 on hand for general use, for larger tasks when more time is required, or when I just want to work at a more relaxed pace. For a job where the close fitting of parts is fussy, I prefer this to the 5 minute stuff. On the other hand, if the fit is clean and easy, with 5 minute stuff, you can often simply hold together two parts being glued, avoiding clamping (although 5 minutes can seem much longer when you have to hold something together with no movement).

    T-88 is similar in thickness to the 5 minute stuff, and again, I have not had to use thickeners or additives (though I did add graphite for color on one repair job). Both are thicker than West 105 stuff, which I have used when I needed its consistency when applying a kevlar patch to Royalex, and where I wanted no question about its use on something to be submerged for some time.

    I have also recently been using West's G-Flex, which is supposed to be less rigid than most epoxies, and is supposed to be better for difficult woods such as white oak. I have not had an opportunity to observe any such differences or advantages, but it certainly is a good general-purpose epoxy.

    For splicing canoe stems, I presume the joint will be somewhat scarf-like, and so will be partially end grain in character. I would be concerned that even during during the quick cure of 5 minute stuff, the open grain of the wood might suck epoxy into the wood and away from the joint faces, leaving you with a glue-starved joint. For such a joint, I would use a slower-curing epoxy -- coating each face of the joint and allowing the wood several minutes to absorb as much of the adhesive as it will, and then re-applying more epoxy just before clamping. Perhaps this is being overly careful, but why run even a small risk just to save a couple of minutes?

    For a stem repair, I would use either the T-88 or G-Flex (or West 105 with appropriate hardener and thickener) in preference to any five-minute product.

    The repair is meant to last a long, long time in an area that is not easy to reach or repair if there is a failure -- what's the rush? And the a 1/2 pint or pint of the 5 minute stuff is about the same price as the same amount as the other stuff.
     
  4. OP
    OP
    tuckerman

    tuckerman Curious about Wooden Canoes

    Thank you Dan and Greg.
    Good, sound advice!
    - Tuckerman
     
  5. donwells1

    donwells1 Curious about Wooden Canoes

    For Years I have gotten my epoxy from Douglas & Sturgis in Richmond, Ca. and have had good luck with it, what I get has a 45 minute pot life with 24 hour cure time and it is Chrystal clear. Their 1 gallon kit I believe is only $98.00 so that is a lot cheaper than some of the others out there.
     
  6. mayday

    mayday East Tennessee Canoeist

    I like RAKA products. Used their 127/350 on my wood strip 9 years ago and after MANY HUNDREDS of miles, its still going strong
     
  7. Jim Dodd

    Jim Dodd LOVES Wooden Canoes

    I'll add another cheer for RAKA, and their 127/350 non-blush hardener!!

    Ever since my first conversation with Larry, I've used nothing else.

    The 6oz cloth comes rolled, and without flaws.

    Jim
     

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