Patterns machined, or made by hand, often require a trained CNC operator or skilled craftsman. If the production is outsourced, patterns can be expensive and time-consuming. With Z Corp 3D Printers users can go from a CAD design directly to a pattern quickly, inexpensively and with very little training. This process can be adopted in foundries, design centers, or pattern shops.

Direct metal casting requires an engineered pattern sent to a Zprinter for printing. This process has four stages: Data Prep, Printing, Reinforcement and Finishing.  These stages are required to produce of the strongest, most durable, long-lasting patterns possible. A 3D CAD package to export their pattern to STL is also necessary. The pattern should be “shelled out” using the STL editor of Magics RP. The result should be a 5-9 mm thick shell, strong without infiltration, yet thin enough so the epoxy infiltrant will fully penetrate through the plaster. First, import the STL file into Magics RP. Then, select the parting (Select: Tools and then Offset Part).

Another step in prepping your data is called “adding ribs”. This is an important step that provides some additional strength to the part after epoxy infiltration. Dividing the shell into sections improves the curing of the epoxy. The ribs do not have to be very thick; only 2-3 mm preferably. First, start with an STL file. Next, import the STL file of your shelled pattern into the ZPrint software. Make certain the cavity is facing down and aligns to the bottom of the build chamber.

Before you send the file to be printed, you must always check it to make sure it is complete with no gaps or errors in the geometry. When you are ready to print send your STL to the printer. Printing time depends on the model, but generally is multiple hours, plus anytime for curing. Printing patterns should be done with a plaster series powder that will provide the greatest strength potential. This will also provide the best finish and accuracy. After printing, remove the parts from the print bed, the bulk of powder and prepare to reinforce with epoxy.

The two stages of reinforcement are crucial to a completely reinforced build. First, users must infiltrate the pattern using Z-Max epoxy. Next they must backfill the pattern’s cavity with a semi-rigid epoxy. Z-Max is the best choice for a very strong, thin epoxy that can penetrate deep into a pattern. The shell requires as much impact strength as possible. The Z-Max epoxy should be applied according to its instructions for use. As a general rule of thumb, you can use 20-25% of the weight of the plaster part in Z-Max.  Make sure to not let the epoxy cure completely before going on to the next step.

Backfilling with epoxy helps solidify the pattern, and gives it a strong anchor point if the pattern is to be screwed to a match plate. Users can do this by simply propping up the pattern and filling the back with epoxy. Make certain that the cavity is filled as close to the top as possible. Once they are infiltrated with epoxy, patterns can be finished. First, sand the cured epoxy-infiltrated pattern with 100-grit sand paper by hand or using power-sanding tools. Next, sand the part until there are few pits in the surface. Finally, coat the part with surface filler making certain to fill in any remaining pits. The pattern can then be mounted to a matchplate by threaded anchors or high strength adhesive.

Infiltration is the process of applying a liquid resin to a printed part to provide strength and specific properties. Z Corp’s latest and greatest infiltrant is the Z-Max™ 90. This new epoxy holds 3D modeling to a new standard of strength, function, and improved resistance to humidity, water and heat. The parts are so strong they can bear the weight of a full grown man as seen in the picture above!

How does Z-Max 90 compare with the original Z-Max? Z-Max 90 is a two-part resin system specifically formulated to effectively penetrate the 3D printed parts. Compatible with all Z Corp materials, Z-Max 90 costs 40% less than the original Z-Max.  Because of its lower viscosity, resin can soak into the porous surface without leaving a thick film on the surface of the part.  Z-Max 90 is easier to use. No measuring is required as kits and pumps are pre-weighed. Time applied to parts is now increased by 40%, and the cure time is still 2 hours at 160°F.

Z-Max 90 also out-performed other infiltrant in high temperature functional testing. Partsinfiltrated with Z-Max 90 offered the highest resistance to heat, proving they can withstand the high temperature environments.  This is possible becausethe matrix created by the powder structure acts as a reinforcing mesh, maintaining a models strength and rigidity.  A heat pre-treatment can also be used for the best results.

Now that you understand the benefits of Z-Max 90 over other infiltrant, learn how easy it is to use! Here are some safe tricks and tips to reach the highest performance of your part. First, always read and understand the MSDS (Materials Safety Data Sheet) prior to using Z-Max.  Make certain you are wearing protective clothing; including gloves and eye protection.

Parts should be sanded prior to infiltration to enhance the look of surface finish. To sand properly, use 100-grit sandpaper and continue to 220-grit sandpaper until the desired smoothness is achieved. Dust masks should be worn when sanding finished parts. Remove any loose material before infiltrating. For best results, dry the part for 2-4 hours at 100°F (40°C). This will allow Z-Max to wick deeper into the part. Once infiltrated parts can be easily drilled, tapped, bonded, and machined.

When applying Z-Max, it is important to always have a spill system in place such as a catch pan, wax paper or a drop cloth. Mix 5 pumps of resin with 2 pumps of hardener into a sturdy plastic container thoroughly for 2 minutes before application Use a paint-brush to apply the Z-Max. Apply multiple thin coats to get maximum surface penetration depth. Do not over–apply. Infiltrated parts should be placed on a non-stick surface, leaving it to cure for 2 hours or until the part is no longer sticky. Users can contact Solid Technologies Inc. for more information on safe practices, and accurate Z-Max 90 application.

The number of 3D CAD seats in commercial use today: one million. However, 10 to 15 million engineers spanning from major manufacturers to small companies need an intuitive 3D CAD software, but are not using it. Instead engineers attempt to explain design concepts to a designer who is required to interpret these ideas effectively. Unfortunately this back and forth results in lost ideas, miscommunications, and less than ideal outcomes. As a result the engineer is completely divorced from the actual design process.

The problem arises when engineers realize that MCAD software is not suitable as an engineering tool. With a steep learning curve it can be difficult to master, resulting in time wasted. Engineers become impatient, understandably, since day-to-day conceptualizing, investigating, and analysis should be happening on the fly. As a result many use 2D sketching and 1D simulation tools to design and analyze 3D which can lead to unproductive distortions. These major errors often remain undiscovered until very late in the design process. Engineers using ANSYS SpaceClaim can work easily and fluently in 3D without interference.

ANSYS SpaceClaim is a tool that every engineer can use. The value of ANSYS SpaceClaim is unmatched. What sets ANSYS SpaceClaim apart is that it was designed with engineers in mind. The creators of ANSYS SpaceClaim understand the constant battle to communicate your ideas with conventional CAD software.  ANSYS SpaceClaim uses bid modeling to enhance communication between departments, manufacturers and clients.  ANSYS SpaceClaim is a better brainstorming tool. This intuitive software was designed to encourage innovation. The best part: conceptualizing in 3D with ANSYS SpaceClaim is easy with the ability to quickly edit, modify, and redesign.

Using ANSYS SpaceClaim on a touch screen is most likely the best way to experience it. The software is so easy to use with Pull, and Move options, it instinctively does what all engineers want to do with a model: pull it apart, move things around, change things up. ANSYS SpaceClaim also accelerates the engineering process. The benefit of designing prototypes faster than your competitors is paramount.