We wanted to give you an in-depth look into why our large format 3D printers are so accurate, consistently within +-.005 in accuracy each time they print. The reasons are fairly simple. The accuracy is due to the fact that our machines are built over the course of 200+ hours with the highest quality components, and with extreme precision. The proof is in our process which we have outlined below.
The Industrial Steel Frame
All of Titan Robotics 3D printers start with a frame built with high quality steel. There are a lot of 3D printers on the market that use plastic, aluminum, or even wood. We believe the frame is one of the core components that keeps the machine from losing accuracy over time. Over the course of time, and through thousands of prints, the steel frame is able to withstand the constant movement of the various mechanisms at high speed. We have found that over time, constant movement can cause a “give” and thus compromise the accuracy of the machine.
Machined for Precision
While the steel frame is one of the core elements, the way in which our steel frames are processed is one of the most important factors contributing to our 3D printer’s accuracy. The steel bars that in the end hold our linear guide rails are precision machined by an industrial CNC mill which is able to grind away the steel until it is extremely flat. This results in a precision machined frame and nearly perfect surface for our linear guide rails to be mounted. This precision, in the end, provides even greater accuracy when printing.
High Quality Profiled Linear Guide Rails
Now that the steel has been precision machined, and the frame has been constructed, it is time to mount the linear guide rails onto the frame. We carefully researched and outsourced the highest quality profiled linear guide rails that we could find. Once they arrive in our shop, we go through the process of mounting the rails onto the frame. The process can take up to an hour per rail because we are constantly measuring and realigning the rails so that they are in excellent alignment. Once they are mounted, we ensure that rails do not have a variant of more than +-.0005in.
Virtually Zero Backlash Ball Screws
Another component that is essential to the accuracy of our large format 3D printers is the use of ball screws which provide virtually zero backlash when in motion. The use of ball screws is not a new concept within the world of industrial machinery, but we feel that it is important to cover as it is an essential component in our large format 3D printers. Belt driven machines can be a good solution used in 3D printers, but they tend to become less precise over time due to the stretch and backlash that can occur within the belt. This is especially true when pushing and pulling larger loads. Ball screw driven machines, however, are precise and relatively low maintenance. The ball screw doesn’t build up backlash or slack compared to belt driven systems. Additionally, a benefit to a ball screw driven machine is longevity and the ability to lockout in all axial directions when an e-stop is required.
The final component that we use is AC servo motors. Most 3D printers on the market today utilize the traditional open loop stepper motor, which is an efficient and cost effective option. While Titan offers these motors as a lower end option, it can eventually leave uncertainty in the minds of the operator. The primary reason a stepper motor is inferior, is because a stepper motor does not know where it is in the print area. The motor simply turns according to the input it is given relying on initial starting position. So, if the stepper motor malfunctions or hits a mechanical snag and “misses a step” then it will cause a cascading effect throughout the entire print. Also, the stepper motor moves in increments and not fluid motion. This incremental movement in 3D printing can create microscopic flaws in the print when extreme precision is needed.
Servo motors, on the other hand, provide a smooth, continual motion which minimize those small flaws. Also, servo motors run in a closed loop system, mean that the servo has positional awareness based on the input signals the motor receives. In short, servo motors will never “miss a step” adding to the reliability of the machine during week long prints.
All of these elements and processes combined is the reason why Titan Robotics 3D printers are extremely accurate. They are designed to allow the operator the ability to start a 100+ hour print job knowing that it will complete with little-to-no defects. The quality of the prints produced by Titan Robotics machines is top tier in the FDM 3D printing industry today.