Any woodworker is likely to work a lot with wood veneers, especially those who work on wooden furniture. A veneer is a thin slice of fine, expensive wood that we typically apply to cheaper wood. The purpose of using veneer is that we get the finish of expensive wood at a fraction of the cost. You can get different types of veneers, which vary according to the kind of wood and type of manufacturing process.
Perhaps, the most neglected aspect of veneers is the substrate to which we attach it. On its own, a veneer is quite flimsy and lacks mechanical strength. It needs a form of mechanical support, and that support comes in the form of a veneer substrate. Veneer substrates come in different types of materials like plywood or particleboard, MDF (medium-density fiberboard) or cheaper wood like poplar and pine.
We also get a backer veneer, which can be found on the reverse side of a veneered surface. This stabilizes the substrate upon which the veneer is stuck. If you don’t add a backer, the substrate may warp over time. The backer veneer is usually cheaper than the surface veneer because it is often not seen, as in the inside of a cabinet.
Different Types Of Veneer Substrates
Knowing about the different types of veneer substrates can be very useful to you as a woodworker. Hence, let’s take a closer look at the commonly-available types we usually come across and how to use them:
Hardwood Or Softwood Lumber Substrate
The issue that you will face with this type of wood is that it expands and contracts as the seasons change. For such a solid wood substrate, you are likely to get rift-cut or quartersawn lumber. The property of this type of lumber is that it is less prone to seasonal changes than flat cut lumber. You will need to use a hard-setting PPR adhesive to fix veneer with this type of substrate. Fixing the veneer requires clamping it with a vacuum press for four to six hours.
Particle Board Substrate
Particleboard makes a reasonably good quality substrate, although it may not meet up to the standards of MDF. Lightly sanding the surface with sandpaper usually provides a better grip for gluing veneer with a particleboard substrate. You can test the substrate by placing a drop of water on the surface of the substrate. If the substrate doesn’t absorb the bead of water in less than ten seconds, then you need to sand it more. Once the particleboard substrate readily absorbs a drop of water, you can start applying veneer glue.
Plywood offers more benefits as a substrate in several ways. It is lighter, provides a better grip, and has less tendency to sag. You don’t need to prepare the surface of plywood before applying glue except to ensure that it is clean. However, if you use plywood as a substrate, you need to be careful about the quality of plywood used.
If you don’t monitor the quality of plywood for your substrate, you could end up with shoddy plywood. Such plywood could peel off easily and damage your veneer. Hence, ensure that the plywood bonding of the plywood is adequately done to avoid your veneer deteriorating later on.
MDF/MDO (Medium Density Fiberboard/Overlay) Substrate
You will often find MDF on some of the better-quality veneered furniture. Being a manmade material, MDF offers uniformity and stability, which results in a flatter and better-bonded veneer. You need to prepare the surface of the MDF substrate similar to the way you prepare particleboard substrate. So, you can check the level of absorption by adding a drop of water. When the drop of water gets readily absorbed in less than ten seconds, your substrate is ready for gluing.
Because metal is not porous, the process for veneering with a metallic substrate varies slightly. You need to start the process by gluing a backer grade veneer to the surface with polyurethane glue. You can use metal-epoxy as well, but this tends to be a mess as well as expensive. Once the glue has cured, you will then stick the veneer to the substrate using veneer glue. You need to use particular grades of wood glues if the surfaces are going to be subjected to high humidity and heat. In such a scenario, we usually use powdered urea resin glue which has a high resistance to seasonal changes.
If you are putting veneer on a drywall substrate, you will do well not to put it directly onto the drywall. First bond a layer of ½” MDF with construction adhesive. After doing this, you can apply a paperbacked veneer. You can also use contact cement or PSA (pressure-sensitive adhesive).
PSA is the standard option for most paperbacked veneers. This comes with a readymade protective backing which you just peel off and press the veneer to the surface. The bond that you get is surprisingly strong. You can also apply a coating of shellac for even better results.
Sometimes hardboard sheets are manufactured using thin and weak glue. This will make it difficult for a durable bond between the veneer and the substrate. However, by sanding the surface and ensuring that you use a hardwood frame on the edges, you can meet with considerable success using an HDF substrate.
Plexiglass or Acrylic Substrate
The main precaution to take while using plexiglass or acrylic is not to allow it to bend. You just need to sand the surfaces to be glued. Once the surface of the substrate is opaque, it is ready to be stuck.
We hope that you found this article on different types of veneer substrates interesting and useful. Although we may not have covered every single type here, we have attempted to include the main ones. If you are a woodworker who regularly handles veneer, this article should help you as a useful guide.
You will now be aware not only about different kinds of veneer substrates but how to use them as well. There is unlimited information available regarding different types of veneers but not enough on veneer substrates. Hence, this article. We hope you will now be able to work expertly on different types of veneers and their substrates
Featured Image by Martin Talavášek