# Threadlocker

## When to Use

Use blue threadlocker when:

- Fasteners are exposed to vibration
- A joint must stay secure over time
- A Nylock nut is not practical

<div contenteditable="false" id="bkmrk-">---

</div>## Polycarbonate Warning

Do **not** use threadlocker in contact with polycarbonate (Lexan) or other stress-sensitive plastics.

- It can cause cracking or “crazing” in the material
- It can weaken plastic parts over time

Instead, use:

- Nylock nuts
- Proper mechanical fastening methods (washers, spacers, correct bolt length)

<div contenteditable="false" id="bkmrk--1">---

</div>## Application

- Apply a small amount to metal threads only
- Avoid excess that could spread onto plastic
- Let the joint fully tighten before curing

<div contenteditable="false" id="bkmrk--2">---

</div>## Key Idea

Threadlocker is a backup for vibration resistance, not a replacement for proper fastener selection or good mechanical design.