Can Solenoids Get Sticky From Improper Usage?

Question

I bought three spring-return, push-type solenoid. I can't remember them being sticky from the start because I only was using one at a time, but they may have been. Now that I tried to work them together, two are so sticky that they have become unusable (even by themselves).

I would like to know whether this may have happened progressively because of pushing them a bit hard (I hardly used them though), or wrong components or because I hooked the three up at the same time.

Here is a bit of info on my setup:

• Spring-return, push-type solenoid. 14 Ohm, 12-24Vdc coil. Intermittent duty
• RECT DIODE 1AMP/400PIV
• 12VDC 3.33A SWITCHING POWER SUPPLY
• N-CHANNEL MOSFET, 55V 22A .06OHM
• Resistors
• Arduino Duemillenove

Answer 1

The potential exists to melt some parts on the interior. I would wash the rod of the solenoid in acetone to remove any residue, and check for visible charring within. If worse comes to worse, try some powdered graphite or white lithium grease to lubricate it.

Answer 2

Are they in any kind of hostile environment? Dusty? Wet? Have you verified the voltage at the solenoid to make sure it really is within spec?

Do you have any side-side forces on the solenoid? Something that would make it harder to move?

Also, your spec on the solenoid says 'Intermittent duty'. What does the manufacturer say that means? Do you ever exceed that spec (leaving it 'on' for long periods of time)?