[Interview Title]

The 3D Printing Breakthrough
Q: When did you discover 3D printing?
A: About four or five years ago, I was selling products on Amazon and looking for new products to develop. I had an idea for a 3D-printed product, so I outsourced the first 10-15 units. They sold quickly, but production couldn’t keep up. I bought my first Prusa 3D printer, reinvested profits, and now I run over 70 printers.
Q: What was your first experience with 3D printing? Was it easy to get into?
A: I started with a cheap Amazon printer, and it was a learning experience. I had to manually level the bed, tweak filament, and simplify prints. It wasn’t smooth, but it taught me how printers work, how to fix them, and what to do when things go wrong. That foundation let me upgrade to Prusa and scale operations.
Q: What’s your background? Are you a mechanical engineer?
A: No engineering background. I have a business degree. My first business was converting wine and whiskey barrels into furniture, sold across North America. That taught me manufacturing basics. When I saw 3D printing’s potential, I recognized it as the next evolution of manufacturing and turned it into a full-time business.

Zac’s 70-printer farm in his basement.

Zac built his own custom software.

Scaling the Farm
Q: Was your business a coincidence or a planned effort?
A: More of a coincidence. I was experimenting with products, and one was 3D printed. The low cost and speed of prototyping let me test ideas fast. It started at home with minimal resources and grew into a full-time operation with employees.
Q: How did you learn maintenance and design?
A: Maintenance came from online research and trial-and-error, figuring out what fails most on my farm and planning to maximize uptime. For design, I use simple tools like Tinkercad for 90% of my products. If I need advanced designs, I outsource, but basic tools get me far.
Q: How do you calculate profit?
A: I focus on $2 per print hour per machine, with a minimum 30% gross profit when sold online. Print hours are my limiting factor, so I use that as the core metric. Low-margin products get cut to keep efficiency high.

Q: What’s the current state of your farm?
A: I run 70 Prusa MK4/MK4S printers and one Prusa CORE One on cargo racks in a 1,100 sq ft basement. Fans and AC control temperature, with air quality sensors and filters. Products print, go into boxes, and ship via Amazon, minimizing inventory.
Q: How did you scale to 70 printers?
A: I started with one printer, added two more when sales outpaced capacity, and reinvested profits. Growth was fast to 50-60 printers, then slower as I focused on optimizing existing ones. Now, software and file tweaks boost efficiency more than new printers.
Q: How data-driven is your operation?
A: Completely. I track filament use, print time, and costs in Excel. I know exactly what each product costs and can forecast months ahead. It’s simple math: one printer at $2/hour for 20 hours/day makes $40, enough to buy more printers over time.
Q: How do you integrate new printers?
A: I swap to a 0.8mm nozzle, set up 5kg filament rolls with custom holders, and connect to my software for centralized control. Setup takes 10 minutes per printer, optimizing for speed and my specific products (black PETG, bulky designs).

Q: Why Prusa printers?
A: Reliability, repairability, and upgradability. I needed printers that last without constant part replacements. Prusa’s open-source approach makes repairs easy, and I’ve upgraded MK3S+ to MK4S without replacing them. Their history in 3D printing also drew me in.
Q: How much maintenance is required?
A: Weekly, we deep-clean one rack (9 printers), checking nozzles, PTFE tubes, bearings, belts, and running calibration. Each printer gets this every two months. It keeps uptime high.
Q: Is electricity a concern?
A: It’s low—about 1.5-2¢/hour/printer, or $200/month for 70 printers. I upgraded to a 200-amp breaker and use dedicated circuits per rack to avoid trips. Setup was the challenge, not ongoing costs.
Q: What’s the state of automation?
A: My software, PrintQue, connects all printers to a central dashboard, distributing jobs automatically. Employees remove parts, reset printers with one click, and the software reassigns jobs. It’s efficient and easy to train on.
Q: How did you build PrintQue?
A: I built it from scratch using AI tools like Claude, ChatGPT, and Grok, despite no coding experience. After a failed outsourcing attempt, I learned AI coding in hours and built it in two weeks, leveraging Prusa’s open-source API.
Q: Future plans for PrintQue?
A: I’m adding auto-ejection G-code to remove parts and restart printers. Next, an analytics dashboard for uptime, filament, and maintenance tracking. Long-term, I’ll support other printer brands for mixed farms.
Zac’s Message
Q: Message to the 3D printing community?
A: Keep pushing boundaries. 3D printing solves endless problems as technology improves. Experiment, buy that next printer, and find product-market fit—solutions people want. That’s the golden goose for building a business.