Outsource 3D Printing or Buy a Printer? A Decision Worksheet

The Short Answer

Buying a printer pays when it will be busy, on materials and part sizes it can handle, run by people who have the time and training to operate it safely. Outsourcing pays when demand is irregular, when you need engineering materials, resin parts or parts larger than one machine prints, or when engineers' hours are the scarce resource. The two also work together: a printer in-house for quick form checks, and outsourcing for the rest. The worksheets below let you decide with your own numbers.

Utilization Decides Most of the Math

A printer's purchase, maintenance and space are fixed costs, so their share of each part depends on how many parts the printer makes. Published cost models assume a busy machine. NIST's review of additive manufacturing costs describes one model (Hopkinson and Dickens) that assumed a single part type produced for a year with the machine operating 90 percent of the time, depreciated over eight years, and another (Ruffo and colleagues) that assumed 100 hours a week for 50 weeks a year. The same fixed cost spread over a few jobs a month is a much larger cost per part. NIST also separates well-structured costs (labor, material and machine) from ill-structured ones such as build failure, machine setup and inventory, which are the ones most often left out of a comparison.

What Owning a Printer Costs Beyond the Purchase

• Ownership: the purchase spread over the years you expect to use it, plus maintenance, spare parts and wear items.
• Labor: file preparation and setup, monitoring, removing parts and supports, post-processing, cleaning and maintenance. Count the hours of the person who will actually do it, at that person's cost.
• Failed prints: the material and machine time lost, plus the time to notice and restart. NIST lists build failure among the costs studies tend to overlook.
• Materials: every material bought and stored for the jobs you run, including the spool or bottle bought for a single job.
• Space: room for the printer, its materials and its post-processing, with the ventilation described below.
• Training and safety: who is trained, on what, and where the procedures are written down.

Materials and Part Sizes: What One Printer Covers

One printer has one build envelope and runs a subset of materials well. Engineering materials bring their own requirements: Polymaker's sheet for its PolyMide PA6-CF recommends a wear-resistant nozzle and keeping the filament at 15 percent relative humidity or less at all times for the best printing results, and describes nylon as hygroscopic. Storing and drying nylon is a standing job, and moisture also changes nylon parts after printing (nylon dimensions and moisture conditioning). Resin parts need a different kind of machine and a chemical handling setup. List the materials and the largest part your next year of work needs, and check them against what one printer would cover. For comparison, we print FDM parts up to 350 × 320 × 325 mm and SLA parts up to 353.2 × 198.7 × 400 mm in one piece, in materials from PLA and PETG to PA6-CF, polycarbonate, Tough Resin and High-Temperature Resin, and one order can mix FDM and SLA parts.

Resin Handling: Skin, Solvents and Waste

Resin printing is chemical handling. NIOSH's guide to safe 3D printing for small businesses notes that some chemicals in liquid resins may cause skin irritation or sensitization, that resin parts are typically washed in a chemical bath (often isopropanol) before post-curing, and that many solvents are flammable. A NIOSH study of 39 commercial resin products found that their safety data sheets listed only some of the skin irritants and sensitizers that laboratory analysis detected. The NIOSH Pocket Guide classifies isopropyl alcohol as a Class IB flammable liquid with a flash point of 53°F.

• OSHA's Hazard Communication Standard requires employers with hazardous chemicals in the workplace to have labels and safety data sheets for exposed workers and to train them to handle the chemicals appropriately.
• NIOSH recommends nitrile or other appropriate chemical-resistant gloves, eye protection when pouring resins or using solvents, and written procedures for receiving and disposing of resins and solvents.
• It also recommends storing small quantities of solvents in well-ventilated areas away from ignition sources, and disposing of waste, including cleaning materials and gloves, under federal, state and local rules.
• Keep a spill kit nearby, and an emergency eyewash station near any process that uses solvents.

FDM Emissions and Ventilation

Filament printers need attention too. NIOSH notes that polymer feedstocks can release ultrafine particles and volatile organic compounds when heated, and that exposure to the two together has been associated with adverse respiratory and cardiovascular effects. A chamber study by researchers at the Illinois Institute of Technology found that ultrafine particle emission rates varied primarily by filament material, and that the VOCs emitted in the largest quantities included caprolactam from nylon-based filaments and styrene from ABS; its authors advise caution when running many printer and filament combinations in poorly ventilated spaces. NIOSH favors engineering controls: ventilated enclosures or local exhaust at the printer, which its guide calls more efficient than general dilution ventilation. It cites a recommendation of at least six air changes per hour in university makerspaces, and a study that found three air changes per hour insufficient for regular use of desktop printers. It also suggests keeping printers in a separately ventilated room that people enter only when needed.

Space and Training

A printer needs more than a corner of a desk: room for materials, a post-processing area, ventilation and, for resin, storage for chemicals and waste. NIOSH recommends including 3D printing in the workplace safety plan, training users on its hazards and controls, and restricting access to the people who need it. Training also covers the craft: preparing files, choosing settings, recognizing a failing print and maintaining the machine. Budget the hours of whoever learns it, and a backup for when that person is out.

Decision Worksheet

Fill in the second column from your own plans and numbers, then read across. The more rows that land in the last column, the stronger the case for outsourcing.

Cost-per-Part Worksheet

To compare like with like, work out an in-house cost per part from your own figures and set it beside an outsourced quote at the same quantity. The structure mirrors the published models in NIST's review, where the machine cost per part is the year's depreciation and maintenance divided by the year's production volume.

• 1. Annual ownership: purchase ÷ years of use, plus yearly maintenance and spares: ____
• 2. Parts you will actually print per year: ____
• 3. Ownership per part, line 1 ÷ line 2: ____
• 4. Material per part, including supports, purges and failed prints: ____
• 5. Staff hours per part × loaded hourly rate: ____
• 6. Space, ventilation, safety equipment and training per year ÷ line 2: ____
• 7. In-house cost per part, lines 3 + 4 + 5 + 6: ____
• 8. Outsourced price per part from a quote at the same quantity, plus shipping: ____

When a Hybrid Makes Sense

A hybrid keeps a printer for what it does well and outsources the rest. A printer down the hall answers a quick shape or fit question without a shipment, which suits early iterations in everyday plastics. Engineering materials, resins, large parts and batches are where owning gets expensive: drying and wear-resistant hardware, a chemical handling program, a bigger envelope, and machine hours. Outsourcing those keeps the in-house printer simple. For batches, see low-volume production and small-batch production.

Test Outsourcing Before You Decide

The least expensive experiment is to price your real parts. Upload recent parts to the quote page and compare the prices with your in-house cost per part from the worksheet; quantity pricing tiers are applied automatically, and the quote downloads as a PDF. The free printability review checks a part's walls, tolerances, orientation and material choice at no cost and with no obligation to order. For purchasing, we accept purchase orders and issue invoices, with net terms available on approval; procurement covers vendor documents and terms. If your parts are still taking shape, what a functional prototype costs helps budget the program either way.