One of the quirks of MJF pricing is that it genuinely rewards a full build. Because the machine fuses a whole layer at a time, the cost is driven largely by how much of the build volume your parts occupy, rather than by the simple count of parts. Understanding this changes how you should think about ordering and when to place a batch.
Getting to grips with nesting helps you get a lot more parts for your money. We optimise the packing on every single job through our MJF & SLS printing service, because squeezing the build efficiently is one of the most effective ways to keep your unit price down without changing the parts at all.
Why packing density matters
Unlike processes that print just one part at a time, MJF can fill the entire build chamber with parts stacked in all three dimensions, since no supports are ever needed to hold them up. The more efficiently your parts nest together, the lower the cost per part becomes, because the fixed cost of running the build is shared across more pieces.
A nearly empty build is expensive on a per part basis, while a densely packed build spreads that running cost and delivers excellent value. This is why ordering a sensible quantity at once almost always beats trickling out single parts over time, where each small build carries its own overhead. It helps to think of the chamber a little like a shipping container, where the goal is to leave as little empty air as possible, because that air is effectively paid for whether or not it holds any parts.
Designing to nest well
Compact parts nest together better than long, thin ones, and parts that interlock or stack neatly use the available space far more efficiently. Hollowing out solid sections, where the design allows it, frees up volume for more parts and cuts the material used as a welcome bonus that lowers the price further.
If you have several different parts to make, printing them together in one build is usually much cheaper than ordering each of them separately at different times. Grouping work is one of the simplest ways to save without changing anything about the parts themselves or compromising on quality. Mixing large and small parts in the same build often works well too, since the little ones tuck neatly into the gaps around the bigger pieces.
Timing your orders
Because a full chamber is the most economical way to print, planning ahead pays off. Combining a few weeks of demand into a single order often costs little more than a small order, yet delivers many more parts for the money you spend.
If your needs are steady, we can suggest batch sizes that keep the chamber well filled each time you reorder. A short conversation about your usage usually reveals an order rhythm that keeps your unit price as low as it can sensibly be. Even a rough forecast of the next quarter helps us suggest a build size that balances your cash flow against the lowest possible price per part.
Ways to cut your cost
A few straightforward choices make a real difference to the price you end up paying for an MJF job. None of them require compromising the part, they simply make better use of how the process is priced and how the chamber fills up.
- Batch multiple parts together into a single build.
- Order in quantities that help fill a chamber.
- Hollow large solid volumes wherever possible.
- Combine your team's parts into one order.
Get the most from each build
Send us everything you need printed and we will nest it for the best overall value, rather than quoting each part in isolation and missing the savings. When you get a quote we will show you clearly how batching your parts together changes the numbers in your favour.