We receive plenty of questions about the 3D print price list, and even more often we receive the question “What would be the price of a hollow 3D printout measuring 12 x 14 x 5 cm?”. It is very difficult to estimate it at a glance because these prices are calculated on the basis of a complex mathematical formula which we have been developing for a long time and which we keep improving all the time. The formula is designed differently for various technologies, but they all have a common determinator. The price of 3D printing is never dependent on the degree of geometric complexity. This is the main difference in price estimation between additive and traditional manufacturing technologies. Here, I will describe the pricing formula for 3 technologies: HP Multi Jet Fusion
, FDM, and 3D metal print – DMLS.
HP Multi Jet Fusion
There are 3 factors in the MJF technology which are taken into account when pricing: the volume of the part, the so-called bounding box, which is the dimensions of the cube in which we can fit the model and the number of identical parts ordered. In the MJF technology, we do not print one part in one process, but we fill the entire working space with parts (for our machine it is a cube of 380 x 280 x 380 mm).
These are usually all the parts ordered on a given day. Special software automatically selects the optimal position of the part so that the chamber is as low as possible while maintaining the correct distance between the parts. This allows us to use less powder to fill the chamber or to fit more details into one chamber. The cost of materials in the Multi Jet Fusion technology consists of two factors: powder– we use 20% fresh powder and 80% of the powder recovered from the previous chambers and so-called agents, two types of ink which allow the powder to become sintered in the right spots. The bounding box tells us how much space in the chamber a given detail will occupy, which is related to the amount of powder we will need to use for printing it. The volume, on the other hand, tells us about the quantity of agents that will be used to manufacture a workpiece. For larger quantities, an additional discount is granted because identical parts are more efficient in the chamber, and we can fit more of them. It is worth looking at an earlier article on how to optimize the cost of the 3D printouts of parts.
In the FDM technology the price list for 3D printing is a lot less complicated. In the case of this technology, we typically print one part in one process (or as much as we can fit on the work platform), and the time and cost of printing is proportional to the volume of material that we need to use for a 3D printout. This consists of two components: the volume of the part and the degree of filling. Just like in powder technologies, parts are usually produced with 100% filling inside, so here we use the so-called honeycomb inside a part more often. The filling should be selected according to the pressure which a given workpiece will be subjected to. We usually choose 50% filling because it is the most optimal.
3D printing in metal
The process of 3D printing in metal is very similar to that of the MJF technology. However, there is one significant difference which affects the way 3D printing is priced. The powder after the process can be reused without the necessity of mixing it with fresh powder. The second important factor is the high cost of the machine, which is why the process duration is of great importance. Therefore, there are two main factors which affect the pricing – the volume of the part and the height in Z-axis (vertical axis during the print of the workpiece). The volume of the part will affect how much powder is used for printing, and the Z-axis height will determine the machine’s operating time. Here, another factor is the geometry of the component and the exact number of “overhangs” under which supporting structures need to be made. This also affects the amount of powder used, as well as the finishing time of the print.No, there is no such thing as a universal “3D print price list” or a formula to price a part in additive technologies. Especially in powder-based technologies, we may take a lot of different factors into account. Mathematical formulas for valuation constitute precious “know-how” of the companies being service providers because they are subject to continuous improvement. They must translate into the actual cost of manufacturing parts, such as the quantity of materials used, the cost of machines, and the working time of operators in the best possible way. The great advantage of 3D print
ing over other manufacturing technologies is that we can calculate the price on the basis of the parameters of a part and there is no need for the subjective human factor. Thanks to this, offers can be automatically generated online, which significantly speeds up the ordering process.