3D FDM printers use filament to produce prints through layer deposition. FDM printing is relatively easier than alternative 3D printing technologies like stereolithography and selective laser sintering.
This is the primary reason why it is the most popular print technology. 48 percent of 3D printers in use are FDM printers.
Another reason why FDM printing is preferred over other printing processes is raw materials. FDM printing has a larger and less expensive selection of materials to choose from ranging from Injection Molding beginner-friendly plastics like PLA to more complicated professional-grade plastics like polycarbonate.
Metal filament has extended the use application of FDM printing. In the next six years, metal is predicted to be the fastest-growing material. Today’s article is not about metal filament, however. Today’s article is on a much softer material, namely wax. In this guide, we explore 3D wax printing and wax casting. What is wax casting? Keep reading to find out.
What Wax Is Used For 3D Printing?
Wax for 3D printing is a material with similar properties to standard wax. 3D printing wax is known as a castable filament. These are filaments that can be used to cast a mold from which an item is created. One of the advantages of castable filaments is they make intricate, complex designs like those found in jewelry possible with 3D printing.
Beeswax was one of the first materials used for casting. In early history, metalworkers used beeswax to forge everything from steel weapons used by soldiers to bejeweled crowns worn by kings.
Wax is, however, not the only castable material used in 3D printing. Other materials like castable resins and polymethyl methacrylate (PMMA/Acrylic) can also be used for casting materials.
The main advantage of using wax as a casting material is that it creates less environmental waste compared to plastic. Wax also does not interact with the material you are casting like acrylic or casting resins most likely will.
The main disadvantage of wax is that it is not innately strong so it does not make for a very durable casting material.
What Is Wax Casting?
Lost wax casting or investment casting is using wax to create a mold. This mold allows you to create a custom item from a material such as gold or silver for jewelry. It can also be used to create dental molds.
The primary use case for wax casting is that it allows you to create complex shapes or patterns that would be difficult or impossible to achieve by 3D printing. It is specifically for once-off molds like what you find in dentures and custom-designed jewelry.
Wax casting using 3D printers is much cheaper and faster than die casting using injection molding. The speed and cost savings are making 3D wax casting the preferred alternative to injection molding in many industries. It can shrink production time from months to days and produce savings of up to 95 percent.
For more on this, check out our post 3D Printing vs Injection Molding; When to Use What?
Aside from filament, the resin can also be used for wax casting.
Resin Printing Wax
The biggest advantage resin printing has over FDM is that it produces more detailed prints. In that regard resin printing is arguably the better technology for wax casting.
There are three main types of resin printing (vat polymerization) technologies namely stereolithography (SLA), masked stereolithography (MSLA), and digital light processing (DLP).
The disadvantage of wax casting with resin is the increased cost. Generally, wax casting with resin printers is much more expensive than with FDM printers. Both the printer and the resin will set you back much more than with a filament printer. Source
How To Select Wax For Casting ?
Not all materials are the same. This applies as much if not more to evaluating different brands of wax as it does to different brands of PLA. When looking for wax or other casting materials for that matter the most important things to note are its shrinkage and melt time.
Casting materials shrink and you need to take this into account when picking your material if you want to avoid having your casts come out smaller than planned. Also, materials differ in the time they take to melt. It’s useful to know how long the material you are working with will take to melt.
Pros Of Wax Printing
- Wax casting is an easier first step into metal printing. It allows you to make molds from which you can start making metal items from softer metals with lower melting temperatures like aluminum and tin.
- Wax casting does not need support materials as conventional 3D-printed items do. It is reasonably sturdy while being printed.
- Wax is a more environmentally friendly filament than plastics. Wax does not produce waste as you can melt it or even make candles out of it.
- Wax gives you the ability to create very complex shapes.
Cons Of Wax Printing
- Cost is the biggest stumbling block for 3D printing wax. This includes the cost of a printer that can print wax and the materials. 3D printing wax can cost up to ten times more than plastic filaments.
- Wax printing is also a slightly more complicated process compared to printing with other materials.
How Long Does 3D Printed Wax Last?
Wax printing is temperature sensitive and has a short lifespan compared to plastics. This makes storage particularly crucial. Wax casts and prints have to be kept cool or they quickly disintegrate. Wax casts are used as once-off molds so are melted away once the investment material, for example, gold or silver is cast.
One way to keep your wax cool is to simply store it in your refrigerator until you are ready to use it.
Can You Put A Candle On 3D Prints?
3D prints can be used as candle holders. However, candles generate heat. For that reason, it is necessary to use a heat-resistant material like ABS. 3D prints can also be used to make silicone molds which are then used to cast wax candles.
While heat resistance is a requirement for candle holders, this does not necessarily rule out materials like PLA or PETG. You can use PLA or PETG for low-burning candles.