Glue and adhesives for architecture models
The architectural model is an essential tool in the design process for architecture students. At Green Mat Workshop, one of the most common questions we receive is, "How do I join these two materials together?" We've noticed that students at numerous universities and colleges often struggle with choosing suitable adhesives or employing the correct glueing techniques.
This comprehensive tutorial is designed to shed light on the world of adhesives, focusing specifically on the best types of glue that architects should use when crafting their models.
We will cover when you should or should not use model glue, which brands of glue to buy and how to apply them. If you take one thing away from this tutorial, stop using UHU All Purpose Adhesive and switch to PVA.
Why your architecture model glue choice matters
If you're reading this guide, it's likely because you're seeking the ideal glue for your model. Alternatively, if someone has directed you to this guide, it might be due to some past adhesive choices that were not ideal. At Green Mat Workshop, we offer courses and tutorials for architects and students in model making, so the topic of glue is a frequent point of discussion!
Scale models serve as a tangible manifestation of your ideas, providing a proposal of what a space could potentially look like. However, if your model is marred by visible glue marks, it can disrupt the illusion.
Making the right glueing choices ensures that the glue remains invisible, enhancing the overall aesthetic of your model. The correct adhesive can streamline the model-making process and save you time on a deadline.
In certain model-making scenarios, such as sketch or concept models, the choice of glue may not be as critical, as a polished looking model might not be a priority. In such instances, tape could be a viable alternative. It's quicker to apply than model glue, less prone to errors, and can be adjusted as needed.
Our guide to tape for architects covers the types of tapes that architects use for drawings, masking and architecture models.
Selecting the wrong glue can:
- Leave visible marks
- Extend drying time
- Emit toxic fumes
- Slow down your process
- Lead to your model falling apart
What to remember when making an architecture model
Regardless of the glue you are using, it’s beneficial to keep your hands and working area clean. Washing your hands frequently can prevent glue or dirt from transferring onto your model. Particularly when working with card, it's easy to unintentionally leave a smudge on the model.
While we mainly recommend non-toxic glues, like PVA, some other glues necessitate the use of gloves and a well-ventilated area.
At Green Mat Workshop, we hold the cutting mat in high regard. If it becomes coated in glue, it loses its flat cutting surface. We recommend glueing on a scrap piece of paper.
So, remember:
- Clean your hands and workspace frequently.
- Consider using masking tape to temporarily hold materials.
- Your cutting mat isn't a glueing mat.
- Some glues require gloves.
- Work in a well-ventilated area when using certain glues.
Essential glues for architecture models
PVA / white glue / wood glue
What is PVA glue?
PVA, or Polyvinyl Acetate, may be familiar to you from your school days, known as white glue, school glue, Elmer's glue or Sobo. Its versatile and reliable nature makes PVA the preferred choice for architecture students. Suitable for porous materials like wood, card, and cloth, PVA is water-soluble and also sold as wood glue available in both interior and exterior grade formulas.
While PVA is generally transparent when dry, not all brands perform in the same way. Be sure to test out an untested PVA before committing to it for your project. Avoid yellow-tinted wood glues, such as Gorilla Wood Glue, as they don't dry clear.
Did you know Gouda cheese is coated in PVA!
How to use PVA wood glue for model making
➊ Pour a medium amount of glue onto a piece of scrap paper.
➋ Use a rigid piece of card to apply the glue. Avoid direct application from the bottle, as controlling the quantity can be tricky.
➌ Apply a minimal amount of glue to the edge of the card - remember, less is more!
➍ Hold the glued edge of the card to the other piece for a few seconds.
➎ They should now hold together.
➏ Proceed with cutting and glueing your next piece!
Remember, using excessive glue can reduce its effectiveness and increase drying time, slowing down your progress.
Benefits of using PVA wood glue for architecture models
- Quick drying when used in small quantities.
- Easy to clean up.
- Creates strong bonds.
- Dries clear.
- Absorbs into materials.
- Free from VOCs (volatile organic compounds).
Our recommended PVA glue for architects
Super glue / Krazy glue / CA glue
What is super glue?
Super glue, also known as Cyanoacrylate or CA glue, is used in various applications, from model crafting to medical care. It's famous for its rapid bonding power, and yes, it can even bond fingers together!
The glue is offered in different viscosities such as liquids and gels. The gels are usually recommended by Green Mat Workshop as they provide better control.
Despite its swift action, there are drawbacks. The bottles often become glued shut, it can leave noticeable marks on your model, offers no time for adjustments, and can be unpleasant to work with.
How to use super glue for models
➊ Ensure the materials are clean and dry.
➋ Keep the glue away from skin and eyes.
➌ Apply only a few small drops - less is more!
➍ Hold the parts together for several seconds.
➎ Apply the glue on both surfaces for challenging materials.
If you use too much glue, it can be sanded or removed with a scalpel. Do not use super glue on plastics as the vapour can cloud and damage plastic surfaces. Plastic welding is a better option.
To set the glue instantly, spray a super glue accelerator (aerosol spray) over the glue.
Benefits of super glue for architecture models
- Binds in seconds, instantly when using an accelerator.
- Effective even in tiny amounts.
- Compatible with almost all materials, but you should use PVA glue for porous substances.
Our recommended super glue for architects
Super glue Kicker aka Accelerant
Epoxy
What is two part epoxy?
Two-part epoxy glue uses a resin and a hardener mixed in equal proportions to create an extraordinarily robust bond.
While similar, epoxy adhesive /or glue differs from epoxy resin which is used in casting. The latter is less viscous for easy pouring and takes longer to set. It's also less sticky, as it's not designed for glueing.
Epoxy liquid glue
Epoxy liquid adhesive is typically sold either as a double syringe or two separate tubes. We advise against no-name brands as they often have an unpleasant odour!
- Adheres to most materials, including wood, metals, and plastics.
- Use when PVA or Super glue won’t work.
- Sets within 2-10 hours depending on whether a rapid formula is chosen.
- Has a sticky and viscous consistency, so careful application is essential, less is more!
- Extremely hard once set.
- Avoid contact with skin.
Our recommended liquid epoxy glue for architects
Araldite 2-Part Epoxy Syringe (Rapid)
Araldite 2-Part Epoxy Syringe (Standard)
Epoxy putty
Similar to liquid epoxy, modelling putty also comes in two parts that, when combined in equal amounts, initiate the hardening process. However, putty has a clay-like consistency, differing from a glue.
- Enables carving and sculpting into organic shapes.
- Binds to most materials, including wood, metals, and plastics.
- Provides 3-4 hours of working time before hardening.
- Becomes extremely hard once set.
- Doesn't shrink.
- Use gloves during application.
The major brand, Milliput, offers putty in a variety of colours, including Yellow/Grey, Terracotta, Silver Grey, Black, and White. Once cured, Milliput can be drilled, sanded, and painted.
Our recommended epoxy putty for architects
Plastic weld
What is plastic welding or solvent welding?
Plastic welding involves joining two similar plastic pieces, such as acrylic or perspex, using a small quantity of solvent (Dichloromethane, Methylene Chloride).
Instead of a glue, the process relies on a minimal melting and fusion of the two plastic pieces.
How to use plastic weld solvent for models
➊ Cut the plastic pieces to have two flat edges or surfaces.
➋ Align the two flat edges together, utilising tape for temporary hold if necessary.
➌ Avoid skin and eye contact. Do not inhale the solvent.
➍ With a small paintbrush, apply the solvent along the seam whilst firmly holding the plastic together.
➎ Capillary action will pull the solvent into the joint.
➏The solvent will evaporate within a few seconds, completing the weld.
Benefits of plastic weld for plastic glueing
- Produces clean, virtually invisible joints, even with transparent materials.
- Ensures no gaps between materials.
- Is a very fast process.
- Results in a very strong bond.
Our recommended plastic solvent glue for architecture models
Foam glue / UHU POR
Contrasting with UHU All Purpose, UHU POR, distinguished by its green label, is specifically formulated for expanded polystyrene, styrofoam, blue foam, or mountboard.
Using other glues can lead to foam degradation or melting. However, PVA might be a viable alternative for larger surface areas.
Our recommended foam glue for architecture model making
Polyurethane glue / Gorilla Glue
Polyurethane glue, primarily recognised as Gorilla Glue (original), is generally not the first choice for scale model making. It is, however, a popular adhesive for larger-scale applications such as furniture assembly or construction.
Notably, the Gorilla Glue brand offers a variety of other adhesive products, such as PVA wood glue, super glue, and more.
How to use Gorilla Glue
For optimal use, dampen the surfaces (as the glue requires moisture to activate), apply the adhesive, and then clamp it (as it needs to cure under pressure).
The glue will expand (foaming up) to three times its applied volume and may take up to 24 hours to fully cure.
Our recommended polyurethane glue
Gorilla Original Waterproof Polyurethane Glue
Spray adhesives
Spray adhesives, like Spray Mount, are designed for joining sheets of paper and card. They are ideal for large, flat areas, such as portfolio layouts or collages.
How to use spray adhesives
➊ Shake for 30 seconds before use
➋ Light mist about 30cm from the surface of one sheet
➌ Combine sheets
➍ Spray outside, over-spray will get everywhere!
Types of spray adhesives
Spray Mount: Repositionable, usually for several days. This is the top choice for architects.
Photo Mount: Permanent, allows for only a brief adjustment period.
Display Mount: More permanent than Photo Mount, also with a short adjustment window.
Our recommended spray adhesives
3M Spray mount
3M Photo mount
3M Display mount
Glue guide: Which glue to use?
PVA
Paper
Card (all types)
Mountboard
Finnboard
MDF
Plywood
Balsa wood
Wood
Cork
Super glue
Scale model people
Scale model trees
3D printed parts
Unusual materials
Epoxy
Plaster
Resin
Unusual materials
Plastic weld
Acrylic (Lucite, Plexiglas, Perspex)
Styrene
ABS
Foam glue
Foamboard (foam core)
Polystyrene (styrofoam, blue foam)
For metal parts see joining metal rods and sheets for models.
Glues to avoid using for architecture models
Why architects should stop using UHU
What is UHU All Purpose Adhesive?
UHU All Purpose Adhesive, a synthetic resin adhesive, holds significant brand recognition as an everyday-use glue.
Although marketed as a clear, quick-drying liquid, we find it doesn't entirely live up to its promise. It doesn't absorb into materials, instead forming a layer on the surface. Nevertheless, it offers adjustability while drying and does not wrinkle paper.
How to use UHU All Purpose Adhesive
➊ Apply a thin layer of glue to one piece.
➋ Press the parts together.
For non-absorbent materials, apply to both sides, let dry, reapply, and then press the parts together.
Why to avoid using UHU for model making
Despite UHU's popularity among makers and creators, its ‘all-purpose’ nature may fall short when it comes to the precision required in architectural model making. Here's why you might want to reconsider using UHU for your projects:
- It can stain materials.
- It remains visible once dried.
- The joints it forms retain flexibility.
- It tends to become stringy.
- It is highly flammable.
- It contains solvents and toxins.
Alternatives to UHU
No glue is universally inappropriate and there are instances where using UHU All Purpose Adhesive is acceptable, such as when the glued parts will be hidden, or when working with unconventional materials. However, when it comes to commonly used materials like card, paper, and wood, PVA (Polyvinyl Acetate) stands out as a superior choice. PVA, or white glue, when applied appropriately, dries faster, forms stronger bonds, and leaves a cleaner finish, making it a more efficient adhesive for architectural model making.
Hot glue is a hot mess for your models
What is a hot glue gun?
Hot glue, glue guns are a form of hot-melt adhesive, they push solid glue sticks through a heated element and the hot glue can be used on a variety of materials.
How to use a hot glue gun
➊ Remove old glue residue while the glue gun is turned off. Avoid using water.
➋ Insert a new glue stick into the back of the gun. You can add a new one whilst the old one is still in use.
➌ Plug in the glue gun and allow 2-4 minutes for it to heat up. Don't lay the gun on its side; utilise the provided stand.
➍ Pull the trigger and squeeze out a small amount of glue, striving to avoid messy strings.
➎ Don't leave the gun on for prolonged periods and ensure you're using it in a well-ventilated area.
Why to avoid using a glue gun for model making
Firstly, glue guns require plugging in and time to heat up, and the requirement to remain plugged in reduces mobility. The glue can drip when not in use, making the process bothersome. They're considered a very clumsy tool in the model glue world due to their large nozzle which applies excessive glue, leaving a conspicuous residue on your model. While some appreciate their fast-drying nature, this often leads to rushed, messy applications.
Alternatives to a glue gun
Hot glue guns may be the solution if all else fails. However, if you've planned your model well, a last-resort option shouldn’t be necessary.
Sustainable glue choices for architects
Our top sustainable choice for architectural model glue is once again PVA wood glue. Free from volatile organic compounds (VOCs) and exhibiting low toxicity, it's safe and easy to clean up thanks to its water solubility.
Considering sustainability on a larger scale, you might ask yourself, is glue always necessary in my model construction? Avoiding glue altogether can lead to models or buildings that are more adaptable and reusable, which minimises waste.
Do you actually need glue in your architecture model?
When planning an architectural model, one of the initial considerations should be the materials you plan to use, such as card or plaster. An equally important consideration is how materials will be joined together. At Green Mat Workshop we have seen many models constructed with minimal use of glue or adhesive.
Have you explored the potential of assembling elements without glue, perhaps through slotting or incorporating visible fixing methods like dowels, brackets, or even sewing into your design? These additional considerations could not only simplify the construction process but also enhance and elevate your architectural designs.
It's worth considering how the components of the actual building, object, or space would be joined together in the real world at 1:1 scale. If you find yourself struggling to glue certain parts of your model, it might be an indication that your design needs rethinking. After all, a model is a design tool, and rethinking and revising are inherent parts of the design process.
While glue can be a useful tool in model construction, it's not always the best solution. Exploring alternative methods of joining materials can lead to innovative design solutions and a deeper understanding of construction techniques. So, the next time you reach for the glue, pause and consider if there's a more creative or realistic way to join your model's components.
Joining metal rods and sheets for models
We often observe students struggling to glue metal rods or sheets together, generally using excessive amounts of glue with disappointing results. Glue isn't really meant for this purpose. Instead, metal components should be joined using mechanical fixing or soldering. To help you navigate these techniques, Green Mat Workshop provides a guide on soldering architectural models for our members.
FAQ
What glue is best for architectural models?
PVA or wood glue is an excellent choice for architectural models. It dries rapidly, is easy to clean, forms strong bonds, dries transparently, and is readily absorbed by materials such as card and wood.
What is the best modeling glue for plastics?
Plastic weld is the ideal choice for plastic models. It gives clean, virtually invisible joints, even with transparent materials.
Is PVA glue good for models?
Absolutely, PVA is our top pick for model making. It dries swiftly, cleans up effortlessly, and creates sturdy bonds. It also dries transparently and absorbs into materials like card and wood easily.
What is the best glue for 3D models?
Super glue or superglue is the best glue for 3D printed models. It bonds in seconds and is effective even in tiny amounts.
What glue is best for building paper models?
PVA glue, often referred to as white school glue, is the best option for adhering paper and card models together. It dries transparently and can be easily applied in small quantities for nearly invisible joins.