Can You Share Design Tips for Bolted Joints That Won't Loosen?

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Designing bolted joints that allow for movement with resistance while preventing loosening requires ensuring that the friction securing the bolt exceeds the friction generated by the clamping effect. Thread locking techniques, such as nyloc nuts or Loctite, are recommended to maintain stability. It's crucial to balance the torque and friction between the threads and the moving parts. Additional design considerations may include using appropriate materials and coatings to enhance grip. Effective design can achieve the desired functionality without compromising joint integrity.
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I'm looking for some info/guidelines on designing bolted joints that are made to move with some resistance/friction...all without loosening the bolt. Think of a legs of a camera tripod; the legs can rotate in and out with resistance, but they never loosen.

It seems the basic idea is that the friction/torque securing the bolt (between the male/female threads) must be greater than the friction/torque created by the clamping effect of the bolt (between the bolt head and the moving part). So, some sort of thread locking technique is necessary (nyloc, loctite, etc).

I would be very interested hear any design guidelines/tips for these types of joints.

Thanks!
 
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jstluise said:
I'm looking for some info/guidelines on designing bolted joints that are made to move with some resistance/friction...all without loosening the bolt. Think of a legs of a camera tripod; the legs can rotate in and out with resistance, but they never loosen.

It seems the basic idea is that the friction/torque securing the bolt (between the male/female threads) must be greater than the friction/torque created by the clamping effect of the bolt (between the bolt head and the moving part). So, some sort of thread locking technique is necessary (nyloc, loctite, etc).

I would be very interested hear any design guidelines/tips for these types of joints.

Thanks!
hmmm...

It sounds like you understand the problem perfectly.

I translate your post as;

"I know how mousetraps work. Can someone give me a better idea for a mousetrap."
 
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