A printer can run 24 hours a day. You can't. Without a plan, that usually means one of two things: the printer sits idle all night because the next job needs you, or you set an alarm to change plates at 3 a.m.
Neither is a good way to run a business. Here's how to schedule print jobs around real life.
The problem: changeovers
A printer only needs you at the changeover: when one job finishes and the next one starts. Remove the parts, clear the plate, start the next print. It takes a few minutes, but it has to happen while you're awake.
When jobs are simply lined up one after another, those changeovers land wherever they land: 2 a.m., the middle of your workday, while you're at dinner.
Step 1: Know your waking hours
Write down the hours you can actually get to the printer. For many home shops, that's before work, after work, and evenings, with the weekends more open. That's your changeover window.
Step 2: Put the long prints overnight
Look at your jobs by length:
- Long jobs (8+ hours) are perfect overnight. Start them before bed and they finish around the time you wake up.
- Short and medium jobs go during the day, back to back while you're around to change plates.
- Very long jobs (18+ hours) can run through a workday and the night after. Plan them so they finish in a waking window.
Step 3: Work backwards from the finish time
The trick is planning when a job ends, not just when it starts. For example, if you go to bed at 11 p.m. and get up at 6:30 a.m., the last job of the evening should end after 6:30 a.m. So:
- A 9-hour job started at 10 p.m. finishes at 7 a.m. Perfect.
- A 5-hour job started at 10 p.m. finishes at 3 a.m. The printer then sits idle for 3.5 hours.
If the only job left is 5 hours, it may be better to run it earlier in the evening and save a longer job for overnight.
Step 4: Fill plates to fit the window
Most slicers let you add parts to a plate. If the overnight gap is 8 hours and your job takes 6, add a few more parts. You get more product from the same changeover, and more profit per print hour.
Step 5: Choose jobs by profit per print hour
When there's a free slot, fill it with the job that earns the most for the time it takes. Gross profit per print hour tells you which one that is. See How to price 3D prints.
Step 6: Plan maintenance into the schedule
Nozzle changes, cleaning, and belt checks take the printer offline. Schedule them into a waking window between jobs instead of waiting for something to break mid-print. See 3D printer maintenance schedule by print hours.
Safety when printing unattended
Running a printer overnight means running it unattended. Keep it on a stable, non-flammable surface, keep the area clear, make sure there's a working smoke alarm nearby, keep firmware up to date, and follow your printer maker's safety advice. If something doesn't look right, don't leave it running.
Why we built this into Nozzlet Works
A spreadsheet can tell you what each job costs, but it can't show you where the changeovers will land. That's why Nozzlet Works has a drag-and-drop calendar with your waking hours built in. Drop jobs onto it, and you can see straight away which ones finish while you're asleep.