When purchasing a 3D printer, you can comprehensively evaluate the printer’s performance and demand satisfaction from the following five aspects.
Before buying, first determine which printer meets your needs and choose the right 3D printer from many brands and models. At first glance, it may seem like a difficult task. Digital data is transformed into physical printing technology, and there are huge differences among printers. Today’s 3D printers can use a variety of materials, which differ in terms of structural properties, characteristic definitions, surface finish, environmental resistance, visual appearance, accuracy and precision, service life, and thermal performance. It is important to first determine the main application of 3D printing, which can guide the selection of the appropriate technology and bring the most effective positive impact to the work. Suitable 3D printers should be selected according to application requirements and key performance indicators that can provide the best comprehensive value. Consider the following specific performance attributes to compare the 3D printers you plan to buy.
1. Printing speed
The meaning of “print speed” is different depending on the supplier and implementation technology. Print speed may refer to the time required for a single print job to print a limited distance in the Z axis (for example, the number of inches or millimeters printed in the Z axis per hour). 3D printers with stable vertical build speed usually use this expression. The vertical printing speed has nothing to do with the geometry of the printed parts and/or the number of parts in a single print job. 3D printers that are fast in vertical construction and have little or no speed loss due to part geometry or the number of printed parts are the first choice for conceptual modeling. Because this type of printer can quickly produce a large number of replacement parts in the shortest time.
Another way to describe printing speed is the time required to print a specific part or specific volume. The printing technology using this description method is usually suitable for quickly printing a single simple geometric part, but it will appear when extra parts are added to the print job, or the complexity and/or size of the geometric shape being printed increases. slow down. The resulting slower construction speed will lead to a prolonged decision-making process and reduce the advantages of personal 3D printers in conceptual modeling. However, printing speed is always as fast as possible, especially for conceptual modeling applications. 3D printers whose vertical construction speed is not affected by the number and complexity of printing are the first choice for conceptual modeling applications because they can quickly print a large number of different models for simultaneous comparison, which can speed up and improve the early decision-making process.
2. Parts cost
The cost of a component is usually expressed as a cost per unit volume, such as a cost per cubic inch or a cost per cubic centimeter. Even with the same 3D printer, the cost of printing individual parts varies greatly due to different geometric shapes. Therefore, it is important to understand whether the cost of the parts provided by the supplier refers to a specific part or the average value of various parts. Estimating the cost of components based on your own commonly used typical component STL file packages is often more helpful to determine your expected component cost. In order to accurately compare the parameter values claimed by different suppliers, it is necessary to understand what is included and not included in the cost estimate.
The part cost of some 3D printer manufacturers only refers to the cost of a certain amount of printing materials, and this amount is only the measured volume of the finished product. This calculation method does not fully reflect the true cost of part printing, because it ignores the supporting materials used, the process loss caused by the printing process and other consumables used in the printing process. There are significant differences in the material usage rate of various 3D printers, so understanding the real material consumption is another key factor for accurately comparing printing costs.
Part of the cost depends on the total amount of materials consumed by the 3D printer to print a given set of parts and the price of the materials used. Generally, 3D printing technology that uses powder materials has the lowest part cost. Cheap gypsum powder is the basic modeling material. Unused powder will be continuously recycled and reused in the printer, so the cost of its parts can reach one-third to one-half of other 3D printing technologies.
There is a type of plastic component technology that uses only one consumable material, which is used both for printing components and support during the printing process. Compared to other plastic component technologies, it usually uses less material as a support material, so it produces a sparse support structure that can be easily cleaned up. Most single-material 3D printers do not produce a large amount of process waste, which makes them extremely cost-effective.
Another type of plastic component technology requires the use of special support materials, but the price of the materials is not high. This type of support material needs to be melted, dissolved or cleaned by spraying water under pressure after printing. Compared with the former, this type of technology often uses a lot of materials for printing support structures. Dissolvable support materials require high-strength, corrosive chemicals for special treatment and cleaning measures. The spray cleaning method requires water inlets and outlets, for which the budget cost of your workplace may increase by several thousand yuan. This treatment is labor-intensive and may result in damage to delicate component details, because water spray cleaning is to remove support materials by means of pressure. In addition, the support material stuck in the groove may not be able to be cleaned due to failure to spray. The fastest and most effective way to clean the support material is the 3D printer that uses wax as the support material to clean it by melting. The meltable support material can be cleaned quickly and in batches with only a special finishing oven, using a minimum of labor, and does not put pressure on the surface of the object, so it will not damage the fragile details. Even the support material stuck in the groove can be cleaned away, which can smoothly print complex geometric shapes and achieve maximum design freedom. The cleaning of the wax support material does not require the use of chemicals, and the removed wax material can be placed together with ordinary garbage without special treatment.
3. Minimum detail resolution
Resolution is one of the most confusing indicators of 3D printers and should be used with caution. Resolution may be written in dots per inch (DPI), z-axis layer thickness, pixel size, beam spot size, nozzle diameter, etc. Although these parameters help to compare the resolution of the same type of 3D printer, it is difficult to compare different 3D printing technologies. The best comparison strategy is to personally use your eyes to identify the finished parts printed by different technologies. Check for sharp edges and corner definition, minimum detail size, sidewall quality and surface smoothness. The use of a digital microscope will help the identification of the finished parts, because this cheap device can zoom in and photograph tiny details for comparison. When conducting qualification tests on 3D printers, it is essential that the printed parts accurately present the design effect. According to the appraisal test method, compromise the quality of the smallest details and reduce the accuracy of the test results.
3D printing manufactures parts by layer by layer, processing materials from one form to another, thereby creating printed parts. There may be variables during processing, such as material shrinkage-during the printing process, compensation must be made to ensure the accuracy of the final part. Powder material 3D printers usually use adhesives, which have the smallest degree of shrinkage and deformation during the printing process, so the accuracy of the finished product is often higher. Plastic 3D printing technology is generally used to process printing materials through heating, ultraviolet light, or both, which increases the risk factors that affect accuracy. Other factors that affect the accuracy of 3D printing include part size and geometry. Some 3D printers provide different levels of printing preparation tools that can fine-tune the accuracy for specific geometric shapes. The accuracy declared by the manufacturer generally refers to the measured value of a specific test component. The actual situation will vary with the geometry of the component, so it is necessary to determine the accuracy requirements of your application field first, and then use the geometry involved in the application Perform a test print.
5. Material properties
Understanding the expected application and the characteristics of the materials required is important for choosing a 3D printer. Each technology has its own strengths and weaknesses, and should be considered as a factor in choosing a personal 3D printer. The number of available materials claimed in the promotion should be carefully examined, because there is no guarantee that all available materials can achieve the real required performance. The most important point: Before making a purchase decision, be sure to test in the intended application and evaluate the printed parts. The detailed parameters of the official release will not describe the stability of the components over time and changes in the use environment. If this is not fully considered and tested, it may cause practical limitations.
For conceptual modeling applications, actual physical characteristics may not be as important as component cost and model appearance. Conceptual models are mainly used to communicate visual effects and may be discarded soon after use. Validation models may need to simulate the effect of the final product and need to achieve functional features close to the final production material. Materials for rapid production applications may need to be castable or resistant to high temperatures. The final use parts generally need to remain firm for a long time.
Each 3D printing technology is limited by specific material types. For personal 3D printing, materials can be roughly divided into non-plastics, plastics, and waxes. You should choose a 3D printer based on which type of material best meets the value and scope of application requirements. Compared with a single 3D printer, the combination of multiple technologies can improve printing flexibility and expand application areas. Generally, compared to using an expensive system device, the combination of two less expensive 3D printers has the same budget, but it can achieve higher value and provide greater application scope and printing capabilities.
Non-plastic materials often use gypsum powder and printable adhesives, and the finished parts are tight and hard, and can become very firm by infiltration. This type of component can represent an excellent conceptual model and provide a certain degree of functional testing without bending requirements. The bright white basic material, combined with the exclusive full-color printing capability, can create realistic visual models without the need for additional painting or post-processing.
Plastic materials can be soft or hard, and some have high temperature resistance. Transparent plastic materials, biocompatible plastic materials, and castable plastic materials are all sold. The performance of plastic parts manufactured by different technologies varies greatly, which may not be obvious in the specifications published by the manufacturers. Some parts manufactured by 3D printers will continue to change characteristics and dimensions over time or in different environments. For example, a common specification parameter used to identify the heat resistance of plastics is “Heat Deflection Temperature (HDT)”. Although HDT is a measure, it cannot predict the availability of materials when it exceeds HDT in practical applications. Some materials may experience rapid degradation of functional properties when the temperature is slightly higher than the specified HDT; while the performance of some materials degrades slowly, thereby expanding the applicable temperature range of plastics. Another example is the effect of humidity on components. Some 3D printed plastic products are waterproof, and some plastic products are porous, which will cause the parts to expand and change size due to moisture absorption. Porous parts are obviously not suitable for high humidity applications or pressurized applications, and may require further labor-intensive post-processing to be suitable for these environments.