Are you a Carpenter, Craftsman repairman, or anything in between? If so, chances are that you need to bond what together, and if this is the case, you have come to the right place. What we’re here to do today is to provide you with an in-depth guide on wood glue. Yes, this is a specific type of glue that carpenters used, thus often being referred to as carpenter’s glue, and is often referred to simply as yellow glue as well. Let’s get right to it, provide you with all the information that you need to know about wood glue.
What is Wood Glue? Two Types
OK, so as you can probably guess, wood glue AKA yellow glue, AKA carpenters glue is used to tightly bond together pieces of wood.
Yes, indeed the name of this glue is very self explanatory.
However, although the name of the glue explains what it is used for, it does not explain what exactly it is. What is important to note for one is that although many kinds of glue can be used to bond word together when we’re talking about wood glue, we’re referring to one of two specific types of glue.
The first type of glue we referring to here is known as PVA glue. PVA stands for polyvinyl acetate. This is a synthetic resin prepared by the polymerization of vinyl acetate. In case you were wondering, yes Poly vinyl acetate is a type of plastic, although quite honestly, not one of the best ones out there, although it does have its uses, such as for the bonding of wood. This is often referred to as wood glue, although there is also another common type that is often used and in all honesty is probably better due to the fact that it’s more water resistant. Keep in mind that PVA glue is a water-based emulsion.
The second type of wood glue that you need to know about is aliphatic resin and this is the one that is generally referred to as carpenters glue. Although both types of glue are considered an ideal for outdoor use, aliphatic resin glue is more heat and water resistant than PVA wood glue.
Whereas PVA wood glue cannot be sanded or painted. Once it has cured, aliphatic resin glue can be painted and cured.
Moreover, another major difference between the two is that PVA is a bit slippery during assembly, whereas yellow glue or aliphatic resin glue has more initial grip. All of that being said, the general applications and overall bond strength of the two is very similar.
The bottom line here is that the two are very similar with aliphatic resin glue having more compounds added to it to create a stronger, more water resistant and more heat resistant glue. Aliphatic resin glue is like PVA glue on steroids.
When was Wood Glue Invented
If we’re talking about polyvinyl acetate, this was first discovered in the year 1912 by Doctor Fritz Klatte in Germany, so it has been around for quite some time, and over the last century, it has become very popular and is used in a wide variety of applications.
Polyvinyl acetate can of course be used to make glue, but it has many other uses as well, such as in the automobile industry for one. However, keep in mind that polyvinyl acetate as an adhesive was not used until the early 1950s.
If we are talking about aliphatic resin glue, AKA carpenter’s glue, this did not come along until much later because remember that carpenters glue or aliphatic resin glue is more or less just PVA glue with some added compounds. Aliphatic resin glue has become extremely popular in the last couple of decades.
How Wood Glue Works
What is interesting to know about PVA wood glue and aliphatic resin wood glue is that they do both work in more or less the same way. Remember that both of these types of glue are technically water based. Therefore they work by evaporation. In other words, once the liquid glues are dispensed from their tubes or containers, they cure by allowing the moisture to evaporate from them.
As the moisture of evaporates, it only leaves behind the other components, either the aliphatic resin or the polyvinyl acetate, which in essence forms a layer of plastic, or very similar to plastic anyway. Both of these types of word glue will work on all types of wood, but something to remember is that what glue does bond better to slightly porous pieces of wood rather than very smooth pieces.
Do keep in mind that if you need a very strong bond, that it is also waterproof, fully sandable and very resistant to heat, you will want to go with aliphatic resin wood glue, not PVA wood glue. Now do keep in mind that that’s because this is a water based glue that requires evaporation to dry, if the relative humidity in the surrounding area is too high, the glue will not dry properly.
The Curing Process
OK, so as we have noted above, wood glue, whether we’re talking about Pve or aliphatic resin glue requires dry air to cure. Remember this these are both water based glues that dry and cure through evaporation. As the water evaporates from the glue, only the other components are left behind, which are essentially plastic.
Now as PVA wood glue cures, it does get very hard, but remember that it does not bond well to very smooth wood. It requires a bit of texture in order to form a solid bond. Something to keep in mind here is that PVA wood glue and aliphatic resin glue both don’t try and cure very quickly.
It takes quite some time for them to dry, and it’s of course because water takes time to evaporate. When it comes to PVA glue and aliphatic resin glue, you’re going to want to clamp the pieces together for at least an hour after having applied the glue.
Moreover, depending on the environment in your end, it can take up to 24 hours or even longer for the PVA glue to cure. Due to the long hearing time of this glue material should not be touched before the curing is complete or else it may compromise the integrity of the bond.
How Strong is Wood Glue
When it comes down to it, although both of these types of glue are ideal for gluing together wood, they really are not all that strong. Remember that glues such as these aren’t really designed for big structural applications or for huge construction projects. Yes, wood glue does form a very tight bond with porous wood and it has the ability to hold up a decent amount of weight.
In general, basic PVA wood glue has the ability to hold up about 300 pounds of weight per square inch, which is not too bad, although when compared to polyurethane glue that can hold upwards of 3,500 pounds per square inch, and two component epoxies that can hold upwards of 6,000 pounds per square inch, wood glue is decidedly weak.
With that being said, aliphatic resin wood glue is a fair bit stronger than basic PVA wood glue. What is however very important to know is that wood glue does stay fairly flexible when it dries. This is of course very important because it means that there is a good deal of impact resistance present.
If wouldn’t glue was too hard and brittle once dry, and the wood was to suffer a heavy impact, the bond would simply snap. What you do need to know here is that PVA wood glue is not really waterproof, it’s not really UV resistant, and there are some solvents that will degrade it too. Now there are some types that are said to be water resistant, but in general PVA glue is not ideal for outdoor use.
If you plan on using wood glue outdoors and you should go for aliphatic resin glue. Aliphatic resin glue contains special additives that make it waterproof and more temperature resistant. All of that said, in terms of overall bond strength and the ability to hold up a certain amount of weight, both of these types of wood glue are pretty much the same.
What is Wood Glue Used for
OK, so based on the name of this glue you can probably guess what this type of glue is used for. And yeah, it means that this section is going to be very short. After all this stuff is called wood glue and we think that that’s about as self-explanatory as it can be.
Yes indeed, wood glue is designed to bond pieces of wood together. That being said, within carpentry and woodworking there are some specific applications that you might use wood glue for, so let’s take a look at a couple of these right now.
- Wood glue is often used to bond together thin pieces of glue, such as if you were putting a piece of wood veneer on an underlying piece of wood. The reason for this is because wood glue can be quite thin and thus it does not leave gaps. It allows the wood pieces to be bonded together very closely and tightly.
- What glue is often used for general crafts and other such purposes, such As for making birdhouses small wooden planters for your plants and other small things like that.
- Wood glue is also often used in furniture making and cabinetry.
- On that same note, with glue can be used to repair small cracks or chips and pieces of board as well as to re bond together a piece of wood that has snapped in half (although it would have to be a small piece of wood).
- Wood glue is often used in combination with either nails or screws when making joints. Just remember that wood glue is best used with porous wood.
What you need to keep in mind here is that most wood glue just aren’t very waterproof and therefore are not ideal for outdoor use. Therefore, doing something like building a shed with wood glue is not ideal.
Popular Brands of Wood Glue
Of course, if you expect to achieve the best results and you need to have the best wood glue. Now there are many different brands of wood glue out there, but not all of them are built the same. Some of the most popular and trusted brand names of wood glue include Titebond, Gorilla Glue, Elmer’s, and Franklin International.
How to Remove Wood Glue
Now, although wood glue is not the most resilient type of glue out there, the fact of the matter is that it is very easy to clean up, especially before it dries. Because this type of glue is water based and uses evaporation as its curing method, it means that if it stays wet, it’s not going to dry or cure. Therefore, before wood glue is completely dry, if you just spray it with some water or use a damp rag, you can pretty easily wipe it away.
Moreover, if you use very basic PVA wood glue, even when it is completely dry, pouring water on it and letting it soak should soften it enough to the point where it can be removed. If the water does not soften it enough, you can always try using rubbing alcohol or acetone to soften or dissolve it. Another thing that can work to soften wood glue to the point where you can scrape it off is to use a hair dryer to heat it up because it’s not overly temperature resistant.
Bad Things About Wood Glue
As you might have guessed by now, in the grand scheme of things, although wood glue is fine for gluing wood, it’s really not the best type of glue, and it’s got quite a few disadvantages that you need to know about.
- Normal wood glue just is not water resistant at all and is not ideal for outdoor use.
- Although this glue is fine for joining small pieces of wood, when it comes down to it, it just cannot bear very much weight.
- Normal wood glue is not resistant to really any kind of solvent. Even something as simple as water.
- Normal wood glue will lose its integrity with high temperatures as it is not heat resistant.
- This type of group does not work well on non porous materials.
Is wood glue toxic?
Is wood glue edible?
Is wood glue stronger than screws?
Can I screw into wood glue?
How long should wood glue dry before removing clamps?
There you have it people, everything you need to know about wood glue, what it is, how it works and more. If you are bonding or repaired, what together chances are almost 100% that you will need wood glue.