How to Choose the Right Adhesive for the Job
DIY GUIDE | CHOOSE THE CORRECT ADHESIVE FOR THE JOB ( 3 Minute Read )
No Clue About Which Glue Is Right For You?
With the plethora of pastes, cements, glues and adhesives available on the market, picking the right product for your project can quickly turn into a sticky situation – especially if you don’t know your PVAs from your CAs! That’s why we are going to show you the difference between all the bonding products out there, by discussing what glue or adhesive to choose for job at hand and what qualities each product has so you can stick to the best.
Let’s start by looking at what you’re going to need the adhesive for. We have compiled a convenient comprehensive adhesive application matrix, which gives you all this info:
NOW LET’S ASK SOME STICKY QUESTIONS:
1. What’s the difference between glue & adhesive?
The terms have become interchangeable nowadays, but glue usually refers to a substance that allows two materials to be bonded together, while adhesive is designed to keep two materials together and can also be used as a coating in some instances. Although both natural and chemical compound adhesives are available these days, glue generally refers to a more natural composition (for instance animal hide glue).
2. What is Glue Sizing?
When machining or sanding a low-density wood or MDF, wood fibres may be too weak to be cut off and will simply fold over. This can often be seen in a fine layer of “peach fuzz” forming on the surface. That’s where glue sizing comes in. It is best to use store bought glue sizing formulas rather than making your own, as it is basically a watered-down PVA adhesive mixture. Apply a layer to stiffen and strengthen the wood fibres, so they can be sanded down easily. Glue sizing can also be applied to the porous edges of wood to prevent over-absorption of glues and finishes, and provide a more even grain colouration. Some believe glue sizing can be used as a method to strengthen a weak adhesive but this does NOT work - rather just stick to the correct adhesive for the job.
3. Is there any extra safety gear or tools I need to have for the job?
It’s a good idea to invest in a box of disposable gloves so your hands don’t get covered in glue. Some adhesives work better if the two items are clamped together after being bonded, so a clamp is also a good investment. Most adhesives are low-odour but if you are sensitive to fumes it is a good idea to get a few dust masks to combat this.
4. What is “Setting Time” and what is “Working / Open Time”?
The time it takes an adhesive to set and dry completely is known as “Setting time”. Some adhesives also allow for a longer period of movability and workability before it starts to set. This is known as “Working Time” or “Open Time”, and means you can still move, adjust or affix the glued surface for a certain period before drying and setting starts. In the case of cyanoacrylate adhesives, the bond will last longer if coupled with a coating of accelerator / activator spray.
5. I don’t need to bond anything I just want to fill a gap or knothole in wood. What do I need?
There are a few adhesives that work well for gap filling, such as hide glue, polyurethane and epoxy adhesives. Most epoxy adhesives can be mixed with a little sawdust and applied into a knothole to create a nearly invisible fill.
LET’S TAKE A QUICK LOOK AT ALL THOSE DIFFERENT TYPES OF ADHESIVES:
PVA Adhesive – This is generally considered to be the “woodworker’s glue” as it performs so well in various timber applications. It is available in Interior, Water-resistant and Waterproof types. For most jobs, a clamp will be a handy extra to ensure the glued surfaces form a strong bond. It’s best not to use too much and to apply to only one of the surfaces, as this can prevent beads of glue from leaking out on the sides once the surfaces are pressed together.
Epoxy Adhesive – For this adhesive, it’s recommended to use gloves as the mixture heats up once blended. Epoxy adhesives are available in two-part mixing, as well as a dual-tube 5-minute setting option. When blending the two-part mixing epoxy, a good rule is to start with a mix of 1 part Hardener & 2 parts Resin. Make sure you mix well, and a business card can be used to even out the surface if a large area was covered with the adhesive.
CA / Super Glue – This the most common household glue, and can be used for a variety of lighter applications that aren’t load bearing. This glue can also be used to mend punctures in rubber tubes.
Contact Adhesive – Also known as Rubber / Contact Cement, most of these adhesives are water and heat resistant and bond instantly. These adhesives are generally best for non-porous materials to be bonded together (i.e. Glass, metals, plastic, etc.) and do not require clamping.
Hide Glue – This glue is made from animal by-product and is particularly useful in applications where movability or even later disassembling of parts is a factor. Many woodworkers like to use this glue in furniture making. It is also used when veneering wood.
Wall Tile Adhesive – This adhesive comes in both powder-based and cement-based options. When working with non-porous tiles such as porcelain, it’s best to use a powder-based adhesive, which has a chemical drying process that does not require water-loss in order for it to dry. This means that water can’t escape from the back of the tile properly, and the cement only dries and affixes properly around the edges of the tile, which results in a tile that isn’t decently stuck to the wall.
Threadlocker – This adhesive is used for securing nuts and washers to the thread of screws and bolts so they stay put and don’t screw loose. It is available in many various strengths, so always ensure you read up on which strength product is required for your particular job. Many service manuals for cars and bikes will specify the strength of product required.
Polyurethane Adhesive – These adhesives are good for both porous and non-porous surfaces, but do not work well on Teflon, silicone, waxy or oily surfaces. Most varieties of this adhesive are able to set in high moisture circumstances, which makes it perfect for fixing boats. It also generally has great UV resistance, and can be sanded, stained and painted over. Once the product is cured it can be food safe. The parts you are bonding with this adhesive have to fit very tightly together. In very dry circumstances, the product will require the surfaces to be pre-dampened in order for it to set properly.
Liquid Nails – This adhesive is available in both Interior and Heavy Duty options. It’s easy to clean up with water. The Heavy Duty option can be used in cabinet-making, countertops, applying brick veneer and a host of other minor construction applications. It also sports a bond that is flexible and impact-resistant, so it works well with wood and MDF. Ensure that you check the packaging, as there are various different types with multiple uses.
You can see a comprehensive list of all the adhesives and their qualities in our qualities table down below:
Did our advice keep you glued to the screen? Is there anything more you would like to know about choosing the best adhesive for your particular job? Luckily, you can slip into your nearest BUCO store today and speak with one of our friendly experts about forming a bond that will last. If you want the best advice and lowest price, just stick with us!
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