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[on:]

Hi folks,

As a total newbie, I'm just trying to put together a little percussion instrument, using 12v 'push' solenoids, but so far I've got a couple of the cheaper ones from Farnell and I'm not sure if they travel far enough when energised to be of use. Can anyone share advice on where to buy decent solenoids, please? I like the look of those Black Knight ones by PED, but they're also quite pricey, and possibly a little more powerful than necessary.

Also, I may as well get a stupid question out the way too. I got these solenoids as they were labelled as 'push', but I was under impression that the thick end of the rod was the 'front' of the solenoid, rather than the thin end. Unless I've been sold the wrong components, it would appear the thin end is actually the front (which shoots/pushes outwards when energised) -- is this correct? In which case the plunger will fall out if the solenoid's pointed upwards, which is less than optimal.

[Reply #1 on:]

Try this web-site:

http://www.mutr.co.uk/

They have solenoids under "Electronic Components" and then "Solenoids and Relays".  But they seem a bit expensive?

There's probably a downloadable PDF with the specification of the Farnell parts, which should show how the pull/push mechanism works.  Most solenoids will "pull" magnetically and then use a spring to return to the "off" position.  You may need to use "pull" solenoids and a simple lever arrangement to get a "push".

It's quite normal for the moving part of a solenoid to be free to fall out!  They're intended to be used within a larger mechanism, and that will hold the plunger in place.

[Reply #2 on:]

Thanks very much for the reply!

Yep, I twigged when I saw Grumpy Mike's MIDI glockenspiel -- he'd put a screw-ring around the end of the plunger to stop it falling out when not active, and also had some foam to stop it clicking when it fell back.

I might try and get some of those tiny grommets to dampen the active click as well as the falling due to gravity when it rests. Think I saw some at B&Q...