We’ve all been there—tightened down a bolt just to have it back out two days later, or worse, seized up so bad you needed heat and a breaker bar to move it. The culprit? Improper—or missing—threadlocker.
At CEM Industrial Supply, we stock Loctite and Permatex threadlockers for every use case, from temporary fasteners to permanent press-fit strength. If you’ve ever wondered which color you should be using—or if you’ve never used threadlocker at all—this guide is for you.
What Is Threadlocker, and Why Should You Use It?
Threadlocker is a liquid adhesive designed to secure fasteners and prevent loosening from vibration, shock, and thermal expansion. It also helps seal threads against corrosion and moisture.
Unlike glue, threadlocker cures anaerobically—that means it hardens in the absence of air, once applied between two metal parts. It’s easy to use, but choosing the wrong type can turn a quick job into a nightmare.
The Contenders: What’s On Our Shelf
Loctite Blue 242 (Removable Strength)
- Use Case: Fasteners you may want to remove again—like valve covers, carburetor bolts, and machine guards.
- Torque Rating: Medium
- Cure Time: Sets in 10 minutes, full cure in 24 hours
- Removal: Hand tools (ratchet/wrench) only
Best for:
- General maintenance
- Threaded fasteners 1/4″ to 3/4″
- Shop techs who want security without making future disassembly a pain
Loctite Red 271 (High Strength)
- Use Case: Permanent or critical fasteners—suspension bolts, heavy equipment, motor mounts
- Torque Rating: High
- Cure Time: Initial set in 10–20 minutes, fully cured in 24 hours
- Removal: Requires heat (about 500°F) and a breaker bar
Best for:
- Industrial builds
- Vibration-prone assemblies
- Bolts you never want coming out on their own
Permatex Threadlocker Red & Blue
- Performance: Similar to Loctite in terms of strength and application
- Value: Slightly lower cost, but with consistent results
- Pro Insight: Red is great for aftermarket automotive work, while Blue is perfect for household and light-duty industrial use
How to Use Threadlocker (Without Regrets)
- Clean Threads First:
Use a wire brush and degreaser to remove oil, dirt, or old threadlocker. - Apply Properly:
- Add a drop or two to the bolt threads only
- Avoid getting it on plastic or painted surfaces
- Do not overapply—more isn’t better
- Assemble and Let Cure:
- Tighten to final torque
- Allow to set for at least 10 minutes
- Avoid disturbing the fastener for 24 hours
Threadlocker Color Code (Quick Chart)
| Color | Strength | Removable? | Best For |
|---|---|---|---|
| Blue | Medium | Yes (hand tools) | General-purpose bolts |
| Red | High | No (heat required) | Heavy-duty, permanent installs |
| Purple | Low | Yes (fingertight tools) | Electronics, small screws |
| Green | Wicking type | No | Pre-assembled fasteners |
What We Recommend at CEM
- For 90% of jobs: Loctite Blue 242—secure, removable, easy to apply
- For permanent installs: Loctite Red 271—just don’t forget your heat gun later
- On a budget or for high-volume use: Permatex Red/Blue gives great value and performance
Final Word: Don’t Rattle Apart
Whether you’re bolting together a gearbox, rebuilding suspension, or locking down a control panel, threadlocker is a cheap insurance policy against failure. Pick the right formula and apply it correctly—and your bolts will stay right where they belong.
Find It at CEM Industrial Supply
We stock full lines of Loctite and Permatex threadlockers—plus cleaners, wire brushes, gloves, and torque tools. Not sure which product you need? We’ll help you find the right color for the job.
Stop by CEM or call us at 517-617-4089 for expert advice, volume pricing, and application tips.