Results 1 to 15 of 15

Thread: epoxy or not?

  1. #1

    epoxy or not?

    I am in the process of reassembling a set of kitchen chairs. Many of the joints are quite loose. I am thinking epoxy would give me more working time while doing the glue up as well as take up some of the "gaps" at the joints. I don't think that yellow wood glue would give me time to line everything up and get them clamped up. I have never used epoxy in this type of application. My concern is the outlay of cash for the large containers. I cannot speculate the next time I will need to use the balance of epoxy I will have to buy. I know I can buy the smaller quantity in the two part syringe type package but think I will need several of these for the chairs. I am concerned by the time I would use up the remainder of the larger containers them may be no good. Any idea on the shelf life once opened? Any suggestions or direction would be great. Thanks in advance. Chris

  2. #2
    Join Date
    Mar 2009
    Location
    Sterling, Virginia
    Posts
    644
    West system is great and I don't think it has a shelf life. The hardener turns amber then gets darker with age but it still works fine. If you can get the epoxy also get some #404 adhesive filler for it. You mix it in to thicken the epoxy to help with filling and sagging on vertical surfaces. They have a good web site with a lot of information.

  3. #3
    Join Date
    Mar 2009
    Location
    Upstate South Carolina, USA
    Posts
    176
    I use epoxy on joints of chairs that I build and it works great. For $25 you could buy more than enough two part epoxy with a 24 hour cure time. I mix in sanding dust to color it, but I have also use artist oil paint in the past. The downside is that it is difficult to to this job neatly. I use blue painters tape to limit wher the epoxy can go, but still even with wiping there is some sanding to get rid of the excess epoxy. But maybe you are neater than I am...guess you could use a glue sringe and a steady hand. If you keep the containers capped the shelf life is more than a year.

    Perhaps you should also consider the chair lock kind of super glue also available. I repaired some antique kitchen chairs for a friend last year, and I used Titebond 1 on the joints that had come completely apart. Then I used chair lock super glue squirted into the other joints, which were loose, and everything worked out okay.

  4. #4
    Epoxy is a good choice for extended working time and gapfilling. It can bond to itself when regluing a failed joint in the future, which is not true of yellow glue. Don't worry about shelf life. If the resin eventually crystallizes it can be fluffed up by heating in a water bath like honey. The hardener will develop a darker color and ammoniac smell but still work. Epoxy works best with rough surfaces (80#). Don't use the 5 minute formulation. Various thickeners are available.

    Epoxy cures in an exothermic reaction, so to extend the working time mix small quantities and spread it out in a wide container to increase surface area. A large quantity of epoxy in a small pot can get smoking hot and nasty very quickly. If using a syringe, put only as much in the syringe as you can dispense in a few minutes.

    Clean up with vinegar, denatured alcohol or acetone. Be sure to wear latex or nitrile gloves as epoxy is a strong skin sensitizer.

  5. #5
    Join Date
    Apr 2013
    Location
    Kansas City
    Posts
    2,652
    I use it all the time for the reasons you note. I like West for the pump system, but prefer T-88 for handling smaller quantities.

  6. #6
    Epoxy is good, but try to get good fitting joints first. If the joints are worn and you can't do anything to tighten them up, epoxy is about the best gap filler.

    But good tight joints are better.

    Mike
    Go into the world and do well. But more importantly, go into the world and do good.

  7. #7
    Quote Originally Posted by Kevin Jenness View Post
    Epoxy cures in an exothermic reaction, so to extend the working time mix small quantities and spread it out in a wide container to increase surface area. A large quantity of epoxy in a small pot can get smoking hot and nasty very quickly. If using a syringe, put only as much in the syringe as you can dispense in a few minutes.

    Clean up with vinegar, denatured alcohol or acetone. Be sure to wear latex or nitrile gloves as epoxy is a strong skin sensitizer.
    Kevin is absolutely correct about even slow epoxy "going off" because of the heat it generates. What I do is put my container of mixed epoxy in a larger container of ice.

    Mike
    Go into the world and do well. But more importantly, go into the world and do good.

  8. #8
    Quote Originally Posted by Kevin Jenness View Post
    Be sure to wear latex or nitrile gloves as epoxy is a strong skin sensitizer.
    Nitrile gloves do not stop acetone or MEK. Found that out when a cut on my hand started burning, then searched out an answer. Latex works though.

  9. #9
    Join Date
    Sep 2004
    Location
    Los Angeles, CA
    Posts
    919
    Use white vinegar to clean up epoxy ooooz out. Really! It works if you wipe off the excess epoxy before it hardens. This trick will save you hours of clean up time. Of course, your project will smell like vinegar for a while!

  10. #10
    Join Date
    Feb 2005
    Location
    Easthampton, MA
    Posts
    986
    You can download the manuals of West System and System Three epoxy. A good source is Jamestown Distributors. Do no buy the five minute epoxy. It's not as strong. Get the slow set for longer open time. Study the manuals thoroughly and don't be afraid to call them up and Jamestown as well. I find going to the source is better than a forum. If anyone knows the product it's the manufacturer and dealer.

  11. #11
    Join Date
    Dec 2003
    Location
    SF Bay Area, CA
    Posts
    15,332
    I like to mix my epoxy in a smallish container and then transfer it to a more shallow one to spread it out (as stated above due to heat if you'll need it for a little while). The main key for epoxy is the get the proportions dialed in pretty tight and then mix it, mix it, mix it, mix it...then mix it again. It is nice not having to sweat it rushing to glue up your 'it was perfect until I glued it up' project that you spent so much time getting just right.

    The other option is to glue in stages. One ought to be able to glue up small sections (sometimes...not always). Glue up one section but put the whole thing together so the glued up section is in the right position. Then take it apart and glue up another section...reassemble. Divide and conquer.
    Wood: a fickle medium....

    Did you know SMC is user supported? Please help.

  12. #12
    Join Date
    Feb 2003
    Location
    Griswold Connecticut
    Posts
    6,926
    Chris

    I don't know where you're at in CT, but epoxy is pretty widely available here. Just about any Marine supply center will have a few different types. A kit can range in size from the two syringe system you've seen, to 5 gallon containers. Don't limit yourself to Home Depot, or Lowe's, at least not in CT. One of the largest Marine Supply Centers in the US, is in Waterford.
    Not all epoxies are "gap filling, some come already premixed with the thixotropic agent ( thickener) in them, others will need to have micro balloons, or wood flour, or some other type of "thickener" added. The System Three, T-88, that Stan referred to is an excellent product. Very forgiving to use. It comes in 16oz. kits. No wood worker would be wasting money having a kit of T-88 at the ready.
    West and System Three have many different formulations available, and it is worth the time to peruse their websites. There are also structural epoxies available, but if your gaps are that big, I'd be plugging the seat and re-drilling the hole. Epoxy open, working time, can be measured in just a few minutes, to hours. I know of a deck that stayed "tacky" all winter, because the wrong temp range epoxy was used.
    I'm sure that epoxy has a shelf life, but it would appear to be in years, maybe decades. The resin will go solid on you, and the hardener can get a little "stiff", but put the container(s) in hot water and it will "re-liquify".

    The downside in using epoxy in the application that you intend, is that you will not have a repairable joint down the line. A traditional Hide Glue will give you a fairly longish open time, and be repairable in the future.
    Last edited by Mike Cutler; 02-24-2016 at 1:44 PM.
    "The first thing you need to know, will likely be the last thing you learn." (Unknown)

  13. #13
    Join Date
    Mar 2003
    Location
    Southport, NC
    Posts
    3,147
    In my shop we always used epoxy for chair repair. The last thing you want is someone to get hurt if the chair collapses. Chairs have to withstand a great and varying stress in use. Hide glue and yellow glues do not provide adequate strength.
    Howie.........

  14. #14
    Epoxy is not a magic bullet. All commonly used wood glues will give a joint stronger than the wood if used within their limitations. Hide glue and pva's do best with a thin glueline. Epoxy, particularly used with additives after wetting out the surfaces with unadulterated resin + hardener, is much more tolerant of poorly fitted joints, thus my recommendation for this situation.

    If you are concerned about the chair collapsing due to glue failure, screwed and glued corner blocks will add a considerable measure of security.

    Whatever glue is used, the joints should be disassembled and cleaned down to bare wood. If hide or pva is used the surfaces should be built back up to a tight fit prior to reassembly. One advantage to epoxy is that it will adhere to itself, so if (when) the chair joints loosen up in the future they can be reglued without sanding back to wood, perhaps by injection without disassembly. Hide glue lends itself best to future dis/reassembly with the use of heat and moisture.
    Last edited by Kevin Jenness; 02-25-2016 at 1:15 PM.

  15. #15
    Join Date
    Oct 2007
    Location
    Dawson Creek, BC
    Posts
    1,033
    I would use West 610. This system can be applied with a normal caulking gun. The volume of glue in these is less than a normal caulking tube because of the mixing arrangement. I also get the product a marine supply company. I wouldn't think twice about the added cost having fixed a few chairs over the years. Along with the benefit of being a good gap filler, epoxy does not require the same clamp force to achieve a proper bond.

    System 3 is good too, but the 24hr cure time is a nuisance compared to 6hr for West.

    http://www.westsystem.com/ss/new-six10-epoxy-adhesive/
    Last edited by Brad Shipton; 02-25-2016 at 1:26 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •