Can I mix DP gears with module gears in one design?

Designing gear systems across imperial and metric standards can quickly get messy. We’ve worked with audio, medical, and industrial clients who ran into sourcing headaches or alignment failures after mixing DP (diametral pitch) and module gears in the same assembly. DP (Diametral Pitch) and Module are incompatible gear sizing systems — they use different units, […]

Do idler gears change the gear ratio?

Many engineers add idler gears to fix spacing or reverse direction—but don’t always know the cost trade-offs. This post clears up confusion around gear ratio, torque, backlash, and support so you can design clean, efficient layouts without overengineering. No — idler gears do not change gear ratio. The ratio depends only on the number of […]

Why must gear contact ratio be > 1?

When designing compact gear trains or small pinions, it’s easy to overlook how contact ratio affects smooth motion transfer. Below a certain point, gears start losing continuous engagement — which can lead to noise, vibration, or even skipped teeth under load. A contact ratio above 1 ensures that at least one tooth pair is always […]

What is gear contact ratio for spur and helical?

Many engineers know contact ratio matters — but few know when it’s good enough, when it’s too low, or when it creates more problems than it solves. We wrote this guide to help product developers and mechanical teams make smarter gear design decisions, especially when noise, wear, or strength are concerns. At Okdor, we’ve supported […]

What contact ratio gives quieter gears and longer life?

Contact ratio is one of the most overlooked drivers of gear noise, smoothness, and wear. Designers often tweak materials or backlash, but neglect how the number of teeth in mesh affects vibration and lifespan. This post aims to clarify when and why contact ratio matters — and how to optimize it without overcomplicating your design. […]