3D Printing Technologies: A Guide for Product Development
3D printing, or additive manufacturing (AM), has revolutionized product development across industries. From rapid prototyping to end-use production, this technology allows designers and engineers to turn ideas into tangible products faster than ever. However, not all 3D printing technologies are created equal. Understanding the different types is crucial for selecting the right method for your product development needs.
In this post, we’ll explore the major types of 3D printing technologies, their strengths and limitations, and how they impact the product development process.
1. Fused Deposition Modeling (FDM)
How It Works
FDM is the most widely used 3D printing method, it’s ubiquitous now and used by everybody from hobbyists to engineers and scientists. It’s accessibility means you print a seemingly endless assortment of items from websites like printables and grabcad.
These printers work by extruding a thermoplastic filament and depositing it layer by layer onto a build platform until you have your final part. Featuring the lowest print quality overall, FDM prints are typically reserved for rapid prototypes that don’t require very detailed features. The finish can be improved by sanding and filling with automotive fillers and painted with a primer and top coats. There are also more exotic finishing methods such as acetone vapour smoothing but we might recommend considering an alternative method (below) if it’s getting this complicated.
Quality has improved in last few years, with significant advances in printing speed and corrective stabilisation built into the newest printers. Layer lines are still visible and the surface can be rough but it’s a lot better than it used to be and acceptable for many applications. The strength of the part is heavily determined by the orientation in the print volume with Z axis significantly weaker than X and Y.
Our recommendation is to choose a good quality filament and get the settings dialed into the machine for the best results. Don’t forget to store the filament in a dry environment or the quality could suffer.
Bambu X1 Carbon at Engineering Lab
In the engineering lab, a designer operates a Bambu X1 Carbon 3D printer using Fused Deposition Modeling (FDM) to create high-quality parts. He removes a finished model from the printer on the magnetic build plate, swapping it out so the printer is ready for the next print.
Key Characteristics
Materials: Common materials include PLA, ABS, PETG, and flexible filaments like TPU. More exotic materials are available such as Carbon Fibre reinforced PLA.
Strengths:
Accessible, fast and cheap
Ideal for rough prototypes and functional parts
Some final products can even be FDM printed
Large build volumes available.
Limitations:
Surface finish is often rough, requiring post-processing.
Limited detail resolution compared to other technologies.
When to Use
FDM is perfect for early-stage prototypes or low-cost functional parts that don’t require fine detail or a polished finish. It’s a great choice for testing fit and form.
Our Verdict
We like FDM for it’s speed and versatility and our printers are running all the time 👍
2. Stereolithography (SLA)
How It Works
SLA printing is a more in depth, multi step process (than FDM) which uses an LCD screen to cure a vat of liquid resin into solid layers using UV light. The end result is extremely detailed, with almost no layering and a close to injection molded finish. The choice of resin types available now is vast, and it’s possible to have rigid, flexible, transparent and even optically clear parts. We’ve even seen self lubricating/nylon type resins on the market for precision engineering applications like plain bearings and sliding elements.
Resin printing is a bit more involved, with an essential IPA (isopropyl alcohol) ultrasonic washing step which is required to remove excess resin that remains on the part after the print is finished. Finally, the part goes into a UV curing station to cure the part and reach the final hardness.
SLA Resin 3D Printer at Engineering Lab
Here at Engineering Lab, a designer is operating an SLA resin 3D printer using Stereolithography technology. The designer focuses on adjusting the settings to ensure the machine runs smoothly while printing a highly precise model.
Key Characteristics
Materials: Resins with properties like transparency, flexibility, or high temperature resistance.
Strengths:
Exceptional surface finish and detail.
Ideal for intricate designs and complex geometries.
Wide variety of material properties for specialised applications.
Limitations:
More expensive than FDM.
Resin parts can be brittle
Limited build volume compared to FDM.
When to Use
SLA is perfect for creating highly detailed prototypes, moulds, and small production runs of intricate or specialised parts. It’s widely used in industries like dentistry, jewellery, and high-end product design. At our facility, we use UniFormation GK3 printers for precise modelling work, including the use of specialist resin that allows exceptional LED light penetration, making illuminated logos and designs look visually stunning.
Our Verdict
SLA delivers so close to injection molded quality that it’s hard to tell the difference sometimes. Shrinkage can be an issue though so if you need very high dimensional accuracy this is something to consider. Our in house SLA setup delivers great quality parts and we use it often. A common approach is to use FDM first and then follow up with a more detailed SLA print if required.
3. Selective Laser Sintering (SLS)
How It Works
SLS uses a high-powered laser to fuse powdered materials (typically nylon) layer by layer. The unfused powder supports the part during printing, eliminating the need for additional supports. The parts have a typically grainy finish but can be placed in a polishing media to deliver a more refined sheen. A good step up in strength and quality, we have even used them for moulding other parts.
SLS Printers at warehouse
Large SLS (Selective Laser Sintering) printers in a factory, taking up significant space and requiring proper ventilation and extraction systems. These printers are actively producing high-quality prototypes and functional parts, with the factory floor organised to accommodate the size and complexity of the machines.
Key Characteristics
Materials: Mainly nylon, with options for flexible or reinforced variants.
Strengths:
Excellent for functional prototypes and end-use parts.
No support structures, allowing for complex geometries.
Durable and mechanically robust parts.
Limitations:
Expensive setup and materials.
Surface finish is rough/textured - but looks good
Limited color options which are typically made in a dye bath.
When to Use
SLS is well-suited for functional prototypes, small production runs, and designs with complex internal structures. It’s frequently used in aerospace, automotive, and medical device industries.
Our Verdict
We like the strength and also how the parts look out of the printer. You can easily install threaded inserts and Nylon is a good base material for many final products and prototypes.
4. Material Jetting (PolyJet/MultiJet)
How It Works
Material jetting deposits liquid photopolymer droplets, which are then cured layer by layer using UV light. Multiple materials can be printed simultaneously for multi-material or full-color parts.
Material Jet Printer
A material jet printer head positioned above the print bed, just after completing a print. The bed is covered with a fresh layer of material, showing the results of the printing process. The printer head is in place, with its nozzle facing down, ready for the next step or to move on to another layer
Key Characteristics
Materials: Photopolymers with customizable properties.
Strengths:
High precision and smooth finishes.
Ability to combine multiple materials and colors.
Excellent for visual models.
Limitations:
High cost of printers and materials.
Parts can be fragile and unsuitable for functional use.
Requires careful handling of materials.
When to Use
Material jetting is perfect for creating highly detailed aesthetic prototypes, color models, and medical applications like anatomical models.
The multi material/multi colour possibilities enabled by material jetting are really the deal breaker here. With well thought out design it can reduce complex assembly and post production steps and allow for built in gaskets, text and identification directly in the component, etc. Mainly used for show models due to the fragility of the final parts.
5. Direct Metal Laser Sintering (DMLS) / Selective Laser Melting (SLM)
How It Works
We’re going to oversimplify here and say “The metal equivalent of SLS”.
DMLS/SLM also use lasers to fuse powdered metal instead of Nylon, layer by layer, to create highly dense, strong parts. Each layer is effectively melted to the previous layer creating >99% dense components. An additional pressurised furness step can be used to get the final 1% of density for the most demanding applications.
Direct Metal Laser Sintering Printer
A Direct Metal Laser Sintering (DMLS) printer example, these are high-power and high price printers. They have the power to create incredible parts in terms of strength and detail from fusing metals.
Key Characteristics
Materials: Metals like aluminium, titanium, stainless steel, and Inconel.
Strengths:
Creates fully dense, mechanically robust parts.
Suitable for aerospace, automotive, and medical industries.
Enables lightweight designs with internal structures.
Limitations:
Expensive machines and materials.
High energy consumption.
Complex post-processing required.
When to Use
DMLS/SLM are used for functional metal prototypes, customized implants, and high-performance aerospace or automotive parts. Many more design options open up compared to even 5 axis CNC machining.
Choosing the Right Technology for Product Development
Selecting the right 3D printing technology depends on several factors:
Stage of Development: Early prototypes may favor FDM for cost-efficiency, while final prototypes might require the precision of SLA or SLS.
Material Requirements: Consider mechanical properties, durability, and surface finish.
Part Functionality: Functional prototypes or end-use parts often require SLS, DMLS, or SLM.
Budget and Timeline: Cost and lead time constraints can influence your choice.
Integrating 3D Printing into Your Workflow
In product development, 3D printing accelerates iterations, reduces costs, and enables innovation. Whether you need quick prototypes, functional testing, or small-batch production, understanding these technologies allows you to leverage their full potential.
At Engineering Lab, we combine cutting-edge 3D printing with expert design and engineering to bring ideas to life. If you’re exploring how 3D printing can enhance your product development, get in touch with us—we’d love to collaborate.
