Every woodworkers does some degree of gluing because gluing in most instances does such an excellent job ... glue joints are almost always stronger than the wood they are holding together. One of the most popular glues is commonly called Yellow Glue (even though some of them are white), Carpenters Glue (even though carpenters seldom use them anymore) but is actually PVA glue or Polyvinyl Acetate. It has been around for over 100 years and changed little during that time ... why mess with success.
Watch it on Youtube: https://youtu.be/Fr515p5uPJw
PVA glues ... as good as it is, does leave us with some problems. One of them is stains when we are gluing boards together ...
For all of us who are using bar clamps ...
gluing boards together with PVA glues, one common problem are stains right at the point where glue runs out of the joint and touches that metal bars on the bar clamps. These stains are worse on some woods than others and the reason for the stain is the glue reacting with the iron in the bars and the tanin in the wood and result is some ugly stains that sometimes can go quite deeply into the wood and can be a real chore to get out.
The solution ... cover the bars with some sort of water proof film, like plastic or wax paper, I prefer thin plastic, it's inexpensive and it's already in my shop in the form of packing tape .. that stretchy kind in a hand roll ... I use it - ALL THE TIME ... check it out here at Amazon
More on gluing boards together ...
And that is getting the glue of after the fact. I still think that wiping PVA glue off right at the gluing stage is best, wipe it off with a damp cloth, then sand when dry, but I seem to seldom do that anymore ... usually what happens is the boards sit overnight, or even for a few days and PVA glue dries very hard and getting it off in this state is a challenge. In the past I have used a sharp chisel but on a few occasions I have had the hardened glue so attached to the wood, that once in a while when I try to take the glue off it clings to the wood underneath and lifts of a sliver of wood with it ... now I have a small trough I need to do something with and usually, it means, cutting the board and re-gluing because wood putty is a very poor solution for anything like this.
The best alternative I have found for taking glue off is a plain old paint scraper that you can find at any hardware store. They are inexpensive and last for years and you can even re-sharpen them. The nice thing with paint scrapers is because the blade is at a different angle than a chisel, I have never had wood lifted, they work well for taking dried glue off
I have long said gluing end grain to end grain is a poor joint ...
And I still stick with that statement but sometimes there just is no other logical answer, and sometimes strength is not really an issue. I have used 2 part - 5 minute epoxy glue for gluing end grain to end grain but there is a very good alternative and that is using PVA glue. The trick is to coat both surfaces you want to glue with a generous primer coat of PVA glue, then let it sit for 10 or 15 minutes. At that point the PVA glue will have semi dried and will have soaked in nicely to the endgrain and sealed it. Now is the time to put an adequet layer of PVA glue on both sides again, then provide moderate clamping and let dry.
This method is a very good alternative to gluing end grain to end grain and gives surprisingly good results.
Sometimes you DON'T want glue on joints...
And the best reason for that is when you are pre-finishing (which I highly recommend). Depending on the finish, you don't want to get any of it into dados or rabbets or any other joints that are going to be glued because the finish can often impare how well the glue will hold so we don't want any finish ending up in joints that will be glued together.
The best way of avoiding getting finish into glue joints, is to cover them with tape and I love the blue painters tape for this. There may be other products that will do and equal or better job, but the blue tape is another one of my go-to worshop products for a variety of solutions.
I have been using one of my "pinners" for many ...
years to help stabilize things I am gluing together. In some cases, where I am gluing 2 or 3 similar pieces together, before I put them into a clamp I will "pin" the ends to stop them from sliding around. It works great to help keep the wood inline so that clamping does the job it's supposed to do
Click here do see an example of an 18 gauge pinner on Amazon
Copyright - Colin Knecht
woodworkweb.com
