Xometry’s 3D printing service offers 7 unique processes and dozens of industrial-grade materials to tackle any job. To reduce the costs of 3D printing parts (without sacrificing speed and quality), product designers and engineers should understand where the major cost drivers are and how to mitigate them.
The two main cost drivers across all additive platforms are machine time and material cost. Machine time includes the time to fuse or join material to make the part as well as the time it takes the machine to warm up, transition to a new layer, and post-process before shipping. Material costs are directly associated with the material used when printing as well as any wasted and unusable material associated with the direct print.
The 5 tips outlined below are suggestions to help you save money when you get an instant online quote from Xometry.
Tip #1: Decrease Part Volume
Materials used in 3D printing processes, such as nylon powder (SLS) or rolls of thermoplastic filament (FDM) are a main cost factor. Thankfully, additive manufacturing processes are very efficient because printers can either recycle some unused material (e.g. non-melted nylon powder that acts as support structure in SLS) or produce minimal waste material (e.g. FDM cartridges that only extrude enough filament to make the part and support structure).
Xometry’s quoting algorithm automatically detects how much material is needed to produce your CAD file, so finding ways to reduce the volume of your part is a great way to bring down the price.
One way to limit volume, but still preserve overall dimensions, is lightweighting. Creating pockets in designs will reduce material usage, making it more cost-effective to build. When creating a pocket, be sure to create an exit hole for un-sintered (SLS and DMLS) or support (PolyJet) material removal.
For FDM printing, changing the infill is a great way to reduce to reduce part volume and cost. Xometry offers three different infill patterns for FDM:
- Ultralight: Xometry’s ultralight infill parts are filled with a single zig-zag pattern. This is the lightest and least expensive infill option.
- Light: Xometry’s light infill parts are filled with a double cross-hatch pattern. This option provides increased rigidity and is lighter than a complete solid infill.
- Solid: Xometry’s solid infill parts are completely filled for the highest density. This is the heaviest and most expensive option.
To learn more about infills and see visual comparisons of each, check out our infills blog post!
Above: a double cross-hatch pattern provides increased rigidity while retaining part strength
Tip #2: Reduce Z-height
3D printers produce parts on a layer-by-layer basis, fusing or bonding one cross-section at a time until the whole object is formed. For powder bed fusion processes, such as SLS, HP Multi Jet Fusion, and DMLS, the machines melt layers of powder and then moves incrementally up to create the next level. For extruding/jetting processes, the material is ejected through a printhead nozzle. SLA and DLS processes balance layers and cure times. For every layer, which varies from 0.001”–0.013” in height depending on the process, there is a mechanical movement which can add a lot of time to a part’s build. Pairing the vertical movement, recoating of material layers, and even incremental automated printhead cleaning can add hours of machine time.
Minimizing the vertical Z-height of the part is a great way to keep printing costs down. Sometimes splitting parts is also more economical than increasing height. With a lower part height, the impact of the machine activity between layers is mitigated and the costs are focused more on direct material costs.
Xometry’s SLS, HP Multi Jet Fusion, FDM, SLA, DLS, PolyJet, and DMLS processes all use printers with various maximum build platform sizes. These are integrated into our AI-based quoting algorithms, which means that parts that can be built lying on their side (horizontally) tend to be more cost-effective than those that have to be built with their longest face in the vertical direction.
Here are some good “best practices’ lengths to keep in mind when designing your part for a particular process. Staying under these will generally ensure a lower-priced part. Another way to think about it is that if you stay under half the available platform size then you can get multiple parts on the build, allowing some overhead costs to be shared.
- SLS Unfilled: Under 13” preferred, with build area up to 13" x 13" x 20"
- SLS Glass Filled: Under 15” preferred, with build area up to 26" x 15" x 23"
- HP MJF: Under 11” preferred, with build area up to 15" x 11" x 15"
- FDM: Under 16” preferred, with build area up to 36" x 24" x 36"
- SLA: Under 16” preferred, with build area up to 29" x 25" x 21"
- Carbon DLS: Under 3” preferred, with build area up to 7.4" x 4.6" x 12.8"
- PolyJet: Under 7” preferred, with build area up to 19" x 15" x 7"
- DMLS: Under 5” preferred, with build area up to 9" x 9" x 9"
Tip #3: Choose the Right Process
Different 3D printing processes have distinct price points, which means choosing the processes that fall within your budget (without compromising part function) can help you minimize costs.
Xometry’s SLS or HP Multi Jet Fusion printing processes using Nylon 12 is nearly always the most cost-effective process to make plastic parts in bulk. This is mostly driven by the fact that SLS parts can be printed in a family build which allows many items to be made “free-floating” in the powder bed. This allows for quantity discounts to be applied to additional items of the same part as well as added unique parts in the same quote. For large flat parts, FDM ABS-M30 or ASA is the go-to process due to the platform’s capacity to build parts quickly with various materials, infill, and color options.
Our most cost-effective process for 3D printing metals is DMLS, specifically with Aluminum material. Complex parts can be created accurately without tooling, which reduces manufacturing lead times from months to days. We also recommend DMLS as an economical choice for a powerful alternative to metal casting in low volumes.
We have built a great process and material decision infographic to help you choose the right 3D printing option for your project. Or, see how the most popular 3D printed parts function and feel by purchasing a 3D Printed Sample Cube which shows off 6 materials in 5 different 3D printing processes.
Tip #4: Isolate and Test Critical Features
While this tip sounds straightforward, it is commonly overlooked. If you are interested in volume production, or a large or more expensive process, it often makes sense to design sample coupons that contain various iterations of features that will appear on your final design. Snap fits, interlocking geometries, all-in-one assemblies, and other features can all be designed with various offsets and sizes on a single test piece without having to order the entire part multiple times.
For example, if a critical feature on a large part is a threaded hole, we recommend just printing the thread to test how it mates before moving to the entire assembly. Alternatively, a beneficial method is the “shotgun approach” which involves creating multiple iterations of the thread, snap, or other feature on one or multiple samples to print and evaluate. Once you find the right CAD parameter, you can input that in your part design for a repeatable outcome. This will ultimately save calendar days and printing costs between prototypes.
Tip #5: Refer Colleagues and Become a 3D Printing Pro
Xometry has two awesome programs to help save costs on your orders through referral credits and discount codes. Xometry’s referral program will give you a unique referral link to share with colleagues who may be interested in Xometry’s manufacturing on demand services. When a referred user signs up, they instantly get $50 in credits that can be used to buy custom parts at checkout. If they order, then you will get $50 of credits, too!
Xometry also has a 3D Printing Pro Membership program designed for those who frequently order 3D printing prints. For a low annual fee, Xometry will supply 5 codes with a value of up to $200 each month. 3D Printing Pro is designed for engineering professionals, medical device designers, product developers, industrial designers, and purchasing teams who use 3D printing on a regular basis.
3D printing complements Xometry’s online manufacturing services. We have trained experts who can help you find cost-saving solutions as well as the path to scale from one to tens of thousands of parts through our Manufacturing as a Service (MaaS) platform. To learn more about all the services and capabilities Xometry offers, see our Complete Production Guide. This guide outlines the major processes and links to useful tools like our free design guides.
This post was originally published on July 17, 2016. It was updated on February 12, 2020.