Hello everybody,

I have a project in which I need to pull ~50 grams on 3mm.
I though about using a commercial pull solenoid but I have some space restriction in my project.
The solenoid should not be wider that 3mm.
I made a prototype with a 2,5mm ext diam plastic tube on which I made ~400 turns with a 34 gauge wire (3 layers ; final length : 2 cm)
When I apply a 5V voltage I get 0.5A and a magnetic force that is able to attract a 3 grams nail but not many more.
I build a shed with stainless steel but did not get much better results.
What should I do to get 50 gram force out of a max 3mm wide solenoid ?
- increase number of turn and length of the solenoid ?
- increase wire gauge ?
Is a small diameter very deleterious for a solenoid ?

Thanks for your help

 

What is your current limit for that 5 volts.

I would probably try a larger gauge wire and less windings.

 

Can you increase length, is 3mm also the length of retraction?
Any limit on current?
Max.

 

Can you increase length, is 3mm also the length of retraction?
Any limit on current?
Max.

Yes I can increase length. Any idea of how many times longer ? Is there a limit of length over wideness ?
3mm is also the length of retraction however the maximum strenght is needed for the last 1mm.
I don't have current limit but at 0.5A, my 34 gauges wires (0.16mm diam) are already quite hot after few seconds.

 

If the retention time is relatively high, Is there any way you can make a magnetic latching relay?
Using a stack of button magnets, maybe.
This way much more current can be applied for a very short time, a PM magnet retains the armature and a reverse pulse releases it.
Otherwise an increase in length may be a question of experimenting.
Max.