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  • glue up trouble

    So guys, I dunno if your with me but finish work is my least favorite part of the project. I'm in the middle of a display case I designed as a gift. I used pine for the country look. The shelves are let into the sides via dado's and there is a back piece which sits into rabbeted edges. As careful as I was, I still had glue marks at the joints. I wiped with a damp sponge but probably not fast enough. Of course its a fairly small piece so it's tough to get in there and sand, especially when the grain shifts at joining pieces.
    My question is what better way to prevent the squeeze and when it happens, how to get it off. The waiting till its gets goopy trick and them pulling it off with a chisel wouldn't have worked cause the clamps were in the way. This was an almost screw free project.
    Thanks in advance,
    RJ

  • #2
    Re: glue up trouble

    RJ, I like to dry fit my pieces and apply blue tape across all joints that will be glued. Litteraly taping the pieces together. Then cut them apart with a razor knife and glue together. When you peal off the tape all glue squeeze out comes off on the tape. Takes a little extra time, but make for a perfect glue up and no finishing problems.
    info for all: http://www.hoistman.com http://www.freeyabb.com/phpbb/index....wwtoolinfoforu --- "I like long walks, especially when they are taken by people who annoy me."

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    • #3
      Re: glue up trouble

      Dan, that's a neat trick. I'm pretty confident in the woodshop, but glueup is the operation I like the least - and cleaning the squeezeout is one reason. I'm going to give your tape method a try!

      I have been using the let-it-firm-up-then-chisel-or-scrape method. I use a lot of clamps, then spend an hour carefully removing one, scraping the (jelled-over) glue in that area, then putting it back, taking off the next one, etc. Access is often difficult. Your tape idea is ingenius!!

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      • #4
        Re: glue up trouble

        Originally posted by papadan View Post
        RJ, I like to dry fit my pieces and apply blue tape across all joints that will be glued. Litteraly taping the pieces together. Then cut them apart with a razor knife and glue together. When you peal off the tape all glue squeeze out comes off on the tape. Takes a little extra time, but make for a perfect glue up and no finishing problems.
        I have heard of doing this but forgot. I do like your technique with actually taping it together and cutting apart. I'll give it a go next time FO SHO!

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        • #5
          Re: glue up trouble

          I use blue tape in some cases.

          At times, I also pre-finish individual parts before assembly. Glue is easily removed from dried poly and such. Pre-finishing also makes the whole finishing job easier when I don't have to paint, sand, paint, sand... in all those uncomfortable and hard to reach corners.
          In order to understand recursion, one must first understand recursion.

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          • #6
            Re: glue up trouble

            Perhaps you may want to revisit your gluing technique?

            too much glue applied will immediately cause the glue squeeze out dilemma.

            What type of glue did you use? If you used the poly type glues a very little goes a long way. Clean up is required after it has cured. The poly squeeze out can be removed with a razor blade or sharp chisel. Never do it while wet, maximum grief will occur, and wear gloves.

            If you use any of the tite-bond type wood glues then clean up should be with a damp sponge immediately after you see squeeze out. Some wood glues do allow stain to work but more times than not you'll be required to sand away the squeeze out.

            Another trick depending upon the size of the glue joint is making saw kerf cut inside the edge. This then allows excess glue a place to go other than outside of the joint. This concept is similar to having grooves or a spiral on a wood dowel. If you use a solid dowel and too much glue you have a mess...The grooved or spiral dowel eliminates the air trapped in the dowel hole and gives some excess glue a place to go.

            Bottom line though, is to use a small brush or glue applicator to apply the glue to the wood.
            A thin coat on both sides [very thin] will always be better than a thick bead on one side. Poly types though, you add glue to one side and add a bit of moisture to the opposite side.

            Today's glue offer different set up times and viscosity. The new wood glues also have a much better chemistry and react faster and better than the old glues of the past. Thus today you do not require a thick application to ensure a well glued joint.

            So the immediate project may require you use sand paper and patience, and future projects will require you improve your gluing technique.


            Cactus Man

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            • #7
              Re: glue up trouble

              Originally posted by cactusman View Post
              ...
              A note on the amount of glue.
              I read in FWW magazine an article by some woodworking big shot. In it he appears to be negating the suggestion that moderate amount of glue should be used. He also rejects the concept of glue starvation through clamping.

              According to him you need to clamp wood very firmly. The amount of clamping will depend on the wood species and the type of glue. The idea is that the glue needs to penetrate the fibers of the wood to reach its maximum strength. Of course clamping will cause some glue to be squeezed out.

              As for wiping the excess soon after clamping, he also rejects the idea, and opts for a wait time of a few minutes (depending on the glue brand) and scraping it off. The idea is that wiping the glue with wet cloth makes it thinner and easier for the glue to penetrate the fibers. That in turn, makes sanding harder.

              Of course wiping or scraping is also a legendary feud of two camps.
              In order to understand recursion, one must first understand recursion.

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              • #8
                Re: glue up trouble

                I took a couple of pictures to show the joints better. I don't know how I could avoid squeeze out when rocking the shelf into the dado.
                Attached Files

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                • #9
                  Re: glue up trouble

                  Rocking the shelves in, sounds like you added the shelves after the box was built, Right? I would have assembled the box on its side with the top bottom and shelves put into the dados and rabbets on that side then add the other side. when dry enough to handle stand up and add the back, base, and crown. EDIT:: by the way, Nice cabinet, should be able to get most of that glue out of the corners with cabinet scrapers.
                  Last edited by papadan; 08-02-2009, 04:09 PM.
                  info for all: http://www.hoistman.com http://www.freeyabb.com/phpbb/index....wwtoolinfoforu --- "I like long walks, especially when they are taken by people who annoy me."

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                  • #10
                    Re: glue up trouble

                    If I could pull the scraper I would but I doubt it would work pulling up. I guess I should try rather than assume. Yes I put it togther and then put in the shelves. That's due to the back in dado's as well. Not rabbeted edges. Hindsight is 20/20 right?
                    Last edited by rjm78; 08-02-2009, 08:22 PM.

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                    • #11
                      Re: glue up trouble

                      Originally posted by darius View Post
                      A note on the amount of glue.
                      I read in FWW magazine an article by some woodworking big shot. In it he appears to be negating the suggestion that moderate amount of glue should be used. He also rejects the concept of glue starvation through clamping.
                      You're also going to find other articles in FWW over the years talking about glue starvation and cautioning against overclamping. As always with FWW, you have to read the individual author's comments and decide if they make sense to you. I've gotten some great info in FWW but also read a lot of stuff in that magazine that makes no sense.

                      I strongly believe glue starvation is a real issue and an important point. The joints don't fail right away, they fail a year or two or three down the road. I've seen this with boards glued up for tabletops. On the other hand, when I have properly fitted joints and moderate clamping force, the project never has problems and seems to last forever.

                      I've seen no strength advantage to overtightening the clamps. Strength in glue joints done even reasonably well just shouldn't be a problem! As we've all experienced, a good-fitting joint with a reasonable amount of glue and moderate clamping force will be considerably stronger than the wood. This is true whether using open grain woods like oak that soak up a bit of glue or closed grain woods like maple that don't soak up glue much if at all.

                      Of couse we're talking long-grain to long-grain joints. For end grain you need to pre-prime the grain to prevent the glue from wicking up the capillaries, or you will definitely have a glue starved joint with poor strength. Even with the priming, end grain glue joints are seldom acceptably strong; I always try to design them out.

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                      • #12
                        Re: glue up trouble

                        Originally posted by Andy_M View Post
                        I've seen no strength advantage to overtightening the clamps.
                        I believe I never mentioned the article proposed overtightening the clamps.

                        Instead, it weighed the wood variety and the type of glue. Various clamps were benchmarked for their clamping strength with suggestions that some clamps may not be sufficiently strong under some gluing scenarios.
                        In order to understand recursion, one must first understand recursion.

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                        • #13
                          Re: glue up trouble

                          Yes, sorry if I implied that. "Overtightening" is my term. I interpreted your comments on the article as suggesting that the best approach was to tighten firmly without worrying about glue starvation, which I consider to be 'overtightening'. Having had the problem, I'm careful to tighten clamps "just enough but not too much" My point is that if your parts fit together well, and you bring your joint together so it's closed with hopefully just a bit of squeezeout, you're going to get excellent strength using normal woodworker's glues like Titebond or Carpenter's. Going beyond that level of clamping force, to the point of a possibly starved joint, is an unnecessary risk (and a good bet to have problems, IMHO). But let your own experience be your guide.

                          I find in wood working, as in many things, that moderation and a gentle touch is usually the best technique. Again, just my opinion.

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                          • #14
                            Re: glue up trouble

                            In case it matters, in my particular project.....I only have one endgrain joint and it included hidden screws also. The joints I referred to are all long grain.
                            I think I'm convinced that my more is best philosophy isn't true when it comes to glue.
                            Curious though, how do you prime a end grain piece? Not with glue I would hope.

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                            • #15
                              Re: glue up trouble

                              Oh yeah, I use glue. Just rub a generous amount into the endgrain and let it dry for 10 or 15 minutes.

                              The idea is that if you don't do this, the open capillaries pull the glue out of the joint and you get the aforementioned starved joint. If you prime, you are essentially clogging up the end grain, preventing the wicking of glue away from the joint. It really does help quite a bit. But endgrain joints still suck.

                              You don't want to prime with shellac or anything like that. Normal yellow woodworkers glue bonds best to (a) wood, and (b) yellow woodworker's glue.

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