How much filament should a print farm keep in stock

Short answer

How much filament a print farm keeps in stock comes down to a simple rule: enough to cover your daily usage through one supplier lead time, plus a safety buffer for a late delivery or a demand spike. There is no fixed number, because every farm’s usage and lead time differ, so the right stock level is your own rate times your own lead time. Too little stops the farm; too much ties up cash and goes wet.

The stock-level rule

The base stock is your daily usage multiplied by the supplier’s lead time in days. If you use a certain amount a day and a new order takes a set number of days to arrive, that product is the minimum that keeps the farm running through a reorder. Add a safety buffer on top for a delayed truck or a rush week, and you have your target stock. Trim the buffer as your lead time proves steady.

The number is yours, not a rule of thumb. A farm that prints all day needs far more than a shop that prints a few jobs a week, and a farm with a two-day supplier needs less safety stock than one with a two-week supplier.

What sets the stock level

Too little vs too much

Too little stock stops the farm, and a stopped farm costs more than the filament. Too much stock ties up cash and goes wet on the shelf, since even sealed spools slowly take on moisture. The right level is the usage-times-lead-time base plus a trimmed safety buffer, tracked in kilograms and rotated first-in-first-out.

For the planning method, the filament inventory planning page covers the levers, and the filament for print farms page covers the workhorse choice.