展示HN：我设计了一款2毫米微型轴承D20环，能够自由旋转20秒。
在过去的几个月里，我一直在实验一个功能性轴承机制可以做到多小，同时仍然保持顺畅、耐用和实用。这个项目源于一个简单的问题：
一个真正的自由旋转轴承可以做到多薄，同时还能处理持续旋转？
大多数你在网上看到的“旋转戒指”都是通过模拟旋转来欺骗——没有真正的轴承，只有松散公差的金属在金属上滑动。真正的微型轴承旋转需要精确、紧密的公差和高表面光洁度，而在一切都需要佩戴在手指上的情况下，这非常困难。
所以我尝试朝相反的方向推进，最终做出了这个：
一个厚度为2毫米的不锈钢戒指，内部有微型轴承轨道和20个钢球，单次轻弹可以自由旋转20秒以上。
机械细节：
• CNC加工的内圈，公差约为0.01毫米
• 通过侧通道加载的20个微型钢球
• 外圈压在轴承壳上
• 无塑料，无衬套，无润滑剂
• 设计能够承受日常佩戴的力量（压缩、扭转、微冲击）
• PVD变体以增强颜色耐久性
• 外表面可以标记1-20，变成一个小随机数生成器
最初的目标纯粹是机械性的——看看是否可以制造出这么薄的轴承。但它最终在单人桌面角色扮演游戏中意外地变得非常实用：当你需要一个快速的随机结果但没有桌面空间，或者当骰子声音太大（在床上玩，通勤时等）。这个戒指静音旋转，最终指向一个单一的数字。
这并不是为了取代骰子；它只是成为了工程挑战的一个有趣副产品。
我为什么在这里发帖
HN社区通常欣赏：
• 微型制造
• 公差
• 加工挑战
• 精密机械设计
• 不寻常的“为什么这个有效？”项目
我很想听听大家的反馈：
• 提高耐用性
• 最小化摩擦损失
• 替代球材料
• 轨道表面处理
• 任何增加旋转时间而不增加厚度的技巧
如果有人有微型轴承或可穿戴机械组件的经验，我将非常感激你的见解。也乐意回答关于制造过程、公差或过程中遇到的失败的问题。
查看原文
Over the past few months I’ve been experimenting with how small a functional bearing-based mechanism can get while still feeling smooth, durable, and useful. This project started from a simple question:
How thin can a real, free-spinning bearing be while still handling continuous rotation?<p>Most “spinner rings” you see online cheat by simulating rotation — there’s no real bearing, just loose tolerance metal sliding on metal. True micro-bearing rotation needs precision, tight tolerances, and high surface finish, which is difficult when everything needs to be wearable on a finger.<p>So I tried to push it in the opposite direction and ended up making this:<p>A 2mm-thick stainless steel ring with an internal micro-bearing track and 20 steel balls that free-spin for 20+ seconds with a single flick.<p>Mechanical details: • CNC machined inner race with ~0.01mm tolerance • 20 micro steel balls loaded through a lateral channel • Outer ring pressed onto the bearing shell • No plastic, no bushings, no lubricant • Built to withstand everyday wearing forces (compression, torsion, micro-impacts) • PVD variant for color durability • Outer surface can be marked 1–20, turning it into a tiny randomizer<p>Originally the goal was purely mechanical — to see if a bearing this thin could be made. But it ended up being surprisingly functional for solo tabletop RPG use: when you need a quick random result but don’t have table space, or when dice are too loud (playing in bed, on a commute, etc.). The ring spins silently and lands pointing at a single number.<p>This wasn’t meant to replace dice; it just became a neat side effect of the engineering challenge.<p>Why I’m posting here<p>HN tends to appreciate: • micro-manufacturing • tolerances • machining challenges • precision mechanical design • unusual “why does this work?” projects<p>I’d love to hear feedback on: • improving durability • minimizing friction losses • alternative ball materials • raceway finishing • any tricks for increasing spin time without adding thickness<p>If anyone has experience with miniature bearings or wearable mechanical assemblies, I’d appreciate insights. Happy to answer questions about the build process, the tolerances, or the failures along the way.