Start with unit economics you trust
Capacity planning cannot rescue an underpriced product. First calculate revenue, selling fees, direct production cost, profit, and machine time for one unit or production batch. Use batch results when parts share setup time or a build plate, because dividing every cost as if each item were printed alone can distort the plan.
Profit Studio uses the estimate as its baseline, then lets a member test monthly profit goals, available printers, productive hours, and alternative prices. The free calculator remains enough to establish the true per-part economics.
Calculate the units required
Divide the monthly profit goal by expected profit per unit and round upward. A $1,000 target with $12.29 profit per unit requires 82 completed units—not 81. That is a sales requirement, while machine capacity is a separate constraint.
Required units = round up(monthly profit goal ÷ expected profit per unit)Calculate practical printer capacity
The theoretical ceiling is available printers multiplied by productive hours, divided by machine hours per unit. Real farms also lose time to changeovers, maintenance, queues, failed attempts, operator schedules, and uneven demand. Set productive hours to an achievable number rather than assuming every printer runs every minute of the month.
Compare required hours with available hours. If the goal exceeds capacity, the useful choices are visible: raise contribution per unit, improve throughput, add justified capacity, lower the goal, or shift toward a more productive product mix.
Measure dollars per constrained hour
When machines are the bottleneck, expected profit per printer hour is often more useful than margin percentage alone. A product earning $8 over two machine hours contributes $4 per printer hour. Another earning $14 over ten hours contributes only $1.40 per printer hour, even though its profit per order looks larger.
When human finishing is the bottleneck, calculate profit per hands-on hour too. This prevents a low-machine-time product with extensive sanding or assembly from appearing more scalable than it really is.
Keep demand separate from capacity
A machine-hour plan says what you can produce, not what customers will buy. Use actual order history to estimate demand by product and season. Avoid buying another printer solely because a spreadsheet can fill its calendar. Additional capacity makes sense when sustained demand, cash flow, workspace, maintenance, and operator time support it.
Run a monthly review
- Compare expected and actual profit per unit.
- Record successful units, retries, scrap, and downtime.
- Find the actual constraint: sales, printers, or hands-on labor.
- Update rates and product profiles when the evidence changes.
- Test price and direct-sale scenarios before adding capacity.
This creates a calm operating loop: quote with current costs, plan from contribution and capacity, record what happened, and improve the next estimate. It is more useful than chasing maximum utilization with products that do not earn enough.