Difference between FDM & SLA 3D Printing
If you’re just starting to explore 3D printing, there’s a good chance you’re running into a lot of terms that you’re not familiar with, and FDM and SLA are sure to be two of them. In fact, whether you’re considering buying a 3D printer or looking for a 3D printing company to get the job done for you, those are two very important terms.
FDM, or fused deposition modeling and SLA or stereolithography are the two most popular types of 3D printing, and while the results are similar, the process is quite different. Here’s what you need to know:
What Is FDM 3D Printing?
FDM or fused deposition modelling printing is the kind of 3D printing you most often see used by consumer level 3D printers. Also known as FFF or fused filament fabrication, these printers use a “filament” or “thread” of thermoplastic materials. This is passed through a nozzle system, where it is heated and melted, before being “printed” in thin layers on your 3D printed item.
While they can produce a serviceable result and are great for prototypes and items that don’t require a high level of precision, they’re not usually the option of choice for top 3D printing companies making high quality products. However, if you’re looking for a cheap 3D printing service, your best bet will probably be one that uses FDS.
What Is SLA 3D Printing?
An SLA 3D printing service will use machines that use a process called stereolithography to product higher quality, more precise results.
Instead of melting plastics in a nozzle before applying them to the piece, SLA 3D printing services use machines that print thin layers of resin, which are then carefully cured with a special kind of light.
Different kinds of resins can be used to achieve different finishes and properties, and SLA 3D printing generally produces a much more precise and accurate product. While it is a little more expensive, if you are looking for the best 3D printing companies, look for those that offer SLA 3D printing. The results will be worth the extra cost.
Comparing FDM and SLA 3D Printing
When you’re looking for a 3D printing company, you might find that your top choices offer different types of 3D printing, and while we’ve already covered the difference in broad strokes, you probably need more information to determine which one is best for you. So, let’s look at this in more detail.
Precision and Quality
As we’ve already mentioned, SLA 3D printing is a more precise option, but you might be wondering how much more precise, or why. Many companies offer both an FDM 3D printing service and an SLA 3D printing service, so which one do you need, and how do you choose?
- FDM 3D printing uses a nozzle to deposit molten material, layer by layer, when building your piece
- Because of the round shape of the nozzle, and the way this process works, there might be small voids between the layers, or some layers might not stick precisely to the layers below
- Layers deposited by an FDM 3D printer can often be seen on the surface of the piece – although various “resolutions” can be used to minimize this
- SLA 3D printing uses very thin layers of resin to build the printed piece
- Each layer is cured between deposits, which means the next layer will bond better
- There will be less visible lines on the surface of the piece
Precision doesn’t matter in all kinds of 3D printing. So, your decision should be based on the piece itself, and what it will be used for. You can also ask any 3D printing services you ask to provide a sample of each type of printing, so you can see the precision and quality you can expect.
Another factor in deciding which 3D printing services might be best for your project is the materials themselves. Different materials have different properties, and some might be better suited to your needs.
Generally, FDA 3D printing is done with various types of plastic, like PLA and ABS. Some FDM 3D printing services also offer higher quality plastic options, like nylon and TPU or even PEI or PEEK in some cases. But not all services will offer all of those plastics, and the cost of the print job will increase according to the cost of the materials.
SLA 3D printing services use resin to produce their printed items, and resin formulations can be customized quite easily. So, you can choose a harder or softer formulation, different colors, properties like heat resistance and more.
All kinds of additives including ceramic, or glass can be added to the resin to provide the properties you need. There are even 3D printing companies that print high quality dental components for dentures, crowns and bridges.
So, if you are looking for a 3D printing company that can produce parts with very specific properties, it might be best to look for one that offers SLA printing. If you just need a part that looks a certain way, you might be able to use an FDM printing company.
Both FDM and SLA printing requires a fairly robust design process before you can make the part in your head a reality.
Your design will need to be rendered in a CAD program, in 3D. It will then need to be saved in a file format that the 3D printer can “read” (although your 3D printing company will give you more information about what they need.)
Next, your design will be uploaded to what is known as “slicer software”, which will digitally transform your design into the slices or layers that will be used to create it. That design will then be used to tell the machine what to print.
If this sounds like a lot of work and highly technical, it is! While there are consumer 3D printers out there, they can be very hard to master, and the results vary wildly. So, if you’re looking for consistent, quality results, hiring a professional 3D printing company is always a good idea.
Professional 3D companies can also advise you about design restrictions. Some materials won’t work well if the “walls” of your design are too thin, or some parts are too small. The top 3d printing companies will give you a full list of all the design dos and don’ts, so you can get the results you want.
Even after your piece is 3D printed, there are still some steps to be completed, whether you choose FDM 3D printing or SLA 3D printing.
The piece will be rinsed in one of a variety of solvents to remove any loose material. This might be done by hand or by special machines.
SLA printed parts might require a little extra time to undergo a process called post-curing, which further hardens and sets the resin.
If your design has required the inclusion of any support parts, these will have to be removed before the part is complete, and the part will probably be inspected to make sure there are no obvious flaws in the piece.
At this point, the 3D printed part is usually ready for delivery, but if you need the part to be primed, painted or otherwise finished, your 3D printing company might offer that service too.
3D Printing Speed
In most cases, the speed to produce 3D printed items are about the same on FDM 3D printers and on SLA 3D printers. However, there is a special product called Draft Resin that cuts the time to print on an SLA printer dramatically.
While this won’t provide the best, most precise results, it does cut the time required to print, and allows you to get time sensitive items like prototypes done quickly.
One of the biggest factors you will need to consider when finding and hiring a 3D printing company is the size of the item you want to print.
Even the top 3D printing companies can’t print any size of item. They will be constrained by the size of the part you want printed. Usually, companies that print using FDM 3D printing can handle larger items, while those that do SLA typically do smaller parts, but that may vary depending on who you contact.
So, when you’re talking to companies that offer 3D printing to find a partner, make sure you mention the size of your designs!
3D Printing Cost
When it comes to cost, there’s no getting away from the fact that FDM 3D printing is the cheaper option, because it’s less precise and the materials and machines are simpler.
SLA 3D printing costs more, but it offers better, more precise results. So, you need to weigh whether precision or price is the dominant factor in choosing a 3D printing service.
The other option is to purchase a 3D printer and do it yourself, instead of hiring one of the top 3D printing companies. If your designs are simple, that might be an option, but you need to remember that this comes with problems of their own, such as:
- Consumer 3D printers are much simpler and can’t handle large or complex 3D printing designs
- 3D printers are also not cheap, and you can expect to pay anything from $2,000 for an entry level FDM printer to over $10,000 for a top-of-the-line consumer SLA printer.
- You will need to buy all of the different materials, filaments and resins you need, and minimum quantities may apply – so you might have to buy more than you need
- You will need CAD software, and know how to produce it to create 3D renderings – or hire a professional at rates of somewhere between $100 and $200 an hour and upwards
- You will need to have slicing software and know how to use it
- You will need finishing chemicals and tools
Aside from the cost of setting up your own 3D printing system, you will also have to spend many hours learning the system, and probably have at least a few failed attempts before you get your project right.
Which means that if you need quality, professional results fast, and you don’t need to produce large quantities, hiring a professional 3D printing company is often the better choice.
If you are looking for a 3D printing company in Dubai, we’d love to talk to you! Arl is a 3D printing company that offers both FDM and SLA services. We’ve been in the business for long enough to have seen the evolution of this cutting-edge technology, and we’re passionate about 3D printing.
Whether you need a quote on a specific 3D printing project or just want to know more about what our printers can do, we’re happy to help. So, reach out by phone or email, and let’s see if we can make your ideas reality!