Custom Machining & Modern Robots

In modern society, every robot comes out from the CAD drawings of Robot designers which tell how it looks and works but can’t come into truth without the help of the machining technologies. With CAD drawings, robot designers are able to take the advantages of computer numerical control equipment, commonly known as CNC prototyping machining, to obtain necessary metal and plastic parts, which can be called as custom machining.

As we all know, robots now are widely used in many industries, accordingly, to be sorted in different categories, such as aerospace, consumer, disaster response, drones, education, entertainment, exoskeletons, humanoids, industrial, medical, military & security, research, self-driving cars, telepresence, and underwater, etc. Each robot has its own unique features, and as a whole, robots vary hugely in size, shape, and capabilities. That’s why custom machining plays an important role in developing robots from robot prototyping to robot machining.

5 Benefits of Custom Machining for Robotic Parts

1. Direct and Easy Customization

As long as CNC engineers get the CAD drawings of robotic parts in a suitable format like a step or igs format, they can write the programming language based on files into the CNC machines, and then the machines will remove material of workpiece in programmed paths to make it same as what in the CAD drawing (Subtractive Manufacturing Technology). Along the machining process, robot designers do not need to get involved and can just put it aside and wait for receiving the real parts they expect.

2. Highly Accurate Machining

Accurate machining is the key to robotic parts that ensure their target functions are well performed. Correspondingly, CNC machines are used to fabricate a workpiece that has a high precision requirement. Generally, it is possible to get an accuracy of up to 0.005 inches / 0.15 mm. The exact accuracy depends on the robot part that is being worked. It can be found that when multiple pieces are being continually worked, CNC machining parts will be much more accurate.

3. Multi Applicable Materials

CNC machines can work plastics, metal, and the number of other materials, which satisfy the requirements on properties and appearance of varied robotic parts. Aluminum and steel are most often used for the arms and bases of the robots to ensure its strength and functionality. Plastics usually are used in the housings or covers of the robots for aesthetic use, and also lower weights. In some cases, for experimental uses, custom machining makes it possible to make the same robotic parts in multiple pieces of different materials.

4. Time-Saving

One of the primary benefits of custom machining is that it can save time and money on finding suitable parts on the markets. Although there are indeed some specified parts with lower prices in mass production, it is not easy to find the exact one of the design needs. How much time could it take to locate used parts that may or may not be efficient, or search for parts on sales that are languishing on the shelf of some unknown parts service shops? In some cases, the loss of time can significantly throw off the production schedule. The right custom machine shop can take the parts’ specifications, create the parts as expected, and offer them in a fraction of the time.

5. Affordability

The amount the robot designer will spend on custom machining if often much less than they will pay for 3D printing (additive layer manufacturing). Although 3D printing does have its place in many industries, currently, due to technical limitations, it has limited the achievable machining accuracy and applicable materials, especially for metal parts. Usually, the costs of 3D printing depend on the parts’ weight. However, robotic parts use metals quite a lot, if, by 3D printing, the large weights will charge unexpectedly high costs. It is more affordable to have custom parts through custom machining, as well as with better quality.

Possible Differences among Machining Shops

Usually, when asking for a quote, the robot designers will tell machining shops specifications of custom robotic arms in material, dimensions, finishing, and assembly. By an overall evaluation, the machining shops will offer their machining solutions which may differ from one to another – machining solutions, including feasible machining changes if needed. Besides the profits difference, what will the differences among machining shops?

1- Machining Processes

3-axis milling, 5-axis milling, turning, grinding, etc… Although the machining process depends on the part structure, one part can be produced in kinds of ways which is a deferred inaccuracy, costs, and machining time. If the machining shop doesn’t have a well understanding of the custom robot, it is possible to offer a high quote with an unnecessary machining process or offer a lower quote that takes long lead time.

2- Finishing Processes

Machined finish only, sand-polishing, mirror polishing, anodization, painting, sandblasting, coating, etc… Except for standard colors, the designer will not have a specified finishing degree usually. If without second checking, take sand-polishing, if only “polish” is required, some machining shops possibly quote by 180# grits sand-polishing, some quotes by 800#, some even quote by 2000# grits…, resulting in different offers.

3- Exclusive Machining

Common custom robotic parts made at machining include gears, bushings, chassis, brackets, arms, and motor mounts… Each may have different focusing features. For example, robotic gears are mechanical parts with cut teeth designed to mesh with teeth on another part so as to transmit or receive force and motion. Although the common CNC machining is able to make qualified gears, to ensure high teeth tolerance, it needs fine machining on a milling machine, resulting in high costs and more time. There is an exclusive machining process called teeth shaping, which is special on gear machining to satisfy different gear specifications easily.

Conclusions

Robots have been developing on a high-speed road, gradually spreading in every corner of life. However, without custom machining, robot designers can only be limited in the first step. Supported by suitable machining technologies, robot industries will go far away in the future. Let machining shops give you a hand!