Make vacuum pre-loaded spherical air bearings without special tools

TL;DR

Learn how to build low-friction air bearings using inexpensive materials like graphite for various applications.

Transcript

today on applied science we're going to talk about air bearings these are kind of like an engineering cheat code because you get so much for so little the parts cost is only a few dollars and I'm going to show you in today's video how to build these without any special tools so besides the super low friction you can also do funny tricks like this i... Read More

Key Insights

• 😘 Air bearings provide a low-cost and high-performance solution for reducing friction in various applications.
• 👱 Graphite is the magic material used in air bearings, offering porosity and softness for efficient operation.
• ❓ Machining graphite can be messy, and dust collection is necessary to prevent its spread.
• 💇 Flat air bearings can be built using PVC pipe fittings and rough-cut graphite, while non-flat air bearings require creative techniques using cutting tools.
• 😘 Vacuum pre-loading can enhance the performance of air bearings by achieving a captive and low-friction design.

Questions & Answers

Q: What are air bearings and why are they considered an engineering cheat code?

Air bearings are devices that rely on a cushion of pressurized air to support and reduce friction between moving parts. They are called an engineering cheat code because they provide high performance and low cost in various applications.

Q: What is the magic material used in air bearings?

The magic material in air bearings is graphite. Graphite is porous, allowing air to pass through it and create an air cushion. It is also soft, reducing friction and minimizing steel-on-steel contact.

Q: Can any type of graphite be used to build air bearings?

Standard grade graphite performs well for air bearings. Various shapes and sizes of graphite can be used, including 10mm-thick plates for spherical or cylindrical bearings. It is not necessary to use special graphite for air bearing applications.

Q: Is machining graphite messy?

Machining graphite can be messy as the dust gets everywhere and is slippery. Dust collection is essential to prevent the graphite dust from spreading to other surfaces. Wear a mask and take precautions while machining graphite to avoid inhalation.

Q: How can flat air bearings be built without custom-fabricated parts?

Flat air bearings can be built using a PVC pipe fitting and a rough piece of graphite cut from a 10mm slab. Sand the graphite on a flat surface using sandpaper to create a flat air bearing. No special tools are required.

Q: What is vacuum pre-loading in air bearings?

Vacuum pre-loading is a technique that uses vacuum pressure to pull a flat air bearing down while air pressure pushes it up. The two forces balance each other, creating a captive air bearing with low friction.

Q: How can non-flat air bearings like spheres or cylinders be made without special tooling?

Non-flat air bearings can be made without special tooling by using a crude but effective method. A cutting tool is created by coating a spherical ball bearing with super glue and 80 grit sandpaper or making a file by cutting slots into the ball bearing. The cutting tool is used to grind the graphite to create a precise fit for the air bearing.

Q: Can 3D printing be used to create air bearings?

Yes, 3D printing can be used to create air bearings. FDM printing can produce objects of the required size, but additional strength and airtightness may be needed. Coating the inside surface with epoxy can improve the air holding ability and strength of 3D printed air bearings.

Summary & Key Takeaways

• Air bearings provide low friction and can be built using inexpensive materials like graphite.

• Graphite is porous and soft, making it ideal for air bearings as it reduces steel-on-steel contact.

• Different types of graphite can be used, with standard grades performing well for air bearings.