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[BusError]

I'd be interested in a small solenoid, with a throw of max 2mm or so, and idealy one that 'sticks' at both ends. Oh something that doesn't need 48V would be even nicer

Anyone has idea and/or a source ?

[bigglez]

Greetings (No First Name Supplied),

I'd be interested in a small solenoid, with a throw of max 2mm or so, and idealy one that 'sticks' at both ends. Oh something that doesn't need 48V would be even nicer

How small (L x W x H)?
How strong (load force required)?
Duty-cycle (Okay to power 100%, or less)?

Please define 'sticks' at both ends. Are you
requesting some form of latching action?
Do you require spring retention at one end of
travel?

Most DC operated relays and closed-ended
solenoids have a non-ferrous mechanical end
stop to prevent residual magnetism from
keeping the armature from being released (to
'stick', if you will).

Comments Welcome!

[lyndon]

With such a small throw a servo with a short horn should work. Will also hold at end of travel.

[BusError]

Sorry for the late reply;

I'm looking into 'electrifying' an old photographic shutter. The mecanical speed selection died (it was built circa 1920 or so!) and I'm reasonably sure that if I were to find a solenoid to operate the shutter blades there would be room enough for a small battery, and an ATTiny. I can even imagine the speed dial to be read via the ADC and work as the original...

Idealy I'd like something that is 3cm long, max. "Duty cycle" I'm not sure, but all I really need is "on / off" with a way to stay "on" without needing powering... I'm unfamilar with "how strong" -- the original was moved by a spring, and is very easy to operate with tweezers for example...

[rmteo1]

Would this work?
http://www.allelectronics.com/make-a-st ... D/-/1.html

MINIATURE 12VDC PUSH-TYPE SOLENOID
Ledex(TM). 0.5" diameter x 1" long tubular solenoid with 3/8" diameter threaded bushing for mounting. 1/16" diameter x 1/2" long plunger. 40 Ohm coil. Operates on 12 Vdc. 1" wire leads.

[lyndon]

I have a few Lucas solenoids a bit larger than that (1.5x0.75") and they are pretty strong.

Have you considered winding your own solenoid? For the amount of pull you describe it shouldn't take much.

[BusError]

OK, so making a solenoid seems a great idea as it turn out. I can make two, with inverse polarity that pull/push the blade actuator lever, on each sides...

So to make a solenoid, I have (isolated) copper wire, and I just need to wind a large amount around a non-conductive core (small plastic tube) where I can slide the metal rod ? How much is 'much' here ? 1 meter ? would thinner wire work better than thicker wire ?

Also, on how to actuate the solenoid; I will have to use some isolation so I was thinking 'mosfet' -- however by looking a bit deeper there seems to be "mosfet drivers" ICs that output short, low current, high voltage and it seems it's just what I want... so I've been wondering if I could use /that/, directly to power the solenoid itself... does that make sense ? Remember I'm a newb; a creative newb (the dangerous kind )
I've read that I need to have good isolation, including reverse current; I wonder if these mosfet drivers have that, and what sort of specs I'd need if I needed a clamping diode..

Thanks for the input so far!