What are the smallest R/C Servo's available?

[Guest]

I'm looking for some really tiny R/C Servos for the gun elevation on my tank model.

I'm not really after any measurable torque, just the absolute smallest size and ability to lift twin machine guns which are not much larger than a ultra micro servo arm!

I'm thinking I might have to adapt a micro servo and try to move it's electronics and gearboxes around to fit along side it or use a pager motor and a potentiometer with my own tiny gearbox.

[Guest]

These are about the smallest and most reasonably priced you are going to get

http://www.servoshop.co.uk/index.php?pid=XYMS37SS&area=Servo

[Guest]

I've got some of those small chinese made servo's - not too sure if they are the 3.7g or 4.7g ones. I could always lop some of the case off and try to build the bits into the turret!

I'm not sure why I'm sticking with 1:35 - It must be the extra challenge!

[wonwinglo]

Alan,the smallest servos are made from muscle wire,it expands and contracts thus giving the necessary movement,the indoor flying lads use it on their tiny radio controlled aircraft.

[Guest]

Have a look on www.aeronutz.flyer.co.uk Loads of micro R/C stuff there.

[wonwinglo]

Those tiny flying models are little short of amazing,they even thin down insulation foam to keep the weight down,colouring is done with marker pens,thanks for the link Duncan.

Have a look on www.aeronutz.flyer.co.uk Loads of micro R/C stuff there.

[Guest]

Barry,

Have you used those muscle wires much? I've been having a look online and haven't had much luck finding the specifications of the wire, i.e. what voltage will cause it to contract and how much a length of it will contract relative to it's length at room temperature.

Is it right that you have to first stretch it by 5% and it will then return to it's prior length when a voltage runs through it.

It should work quite well to raise and lower one of the smaller guns on the tank. The only problem is the wire will need to be fairly short and probably wont allow for much movement.

[wonwinglo]

Never used it myself Alan just seen the models in action,you can get all the info that you want from Coventry activity Toys

Sales@Activity-Toys.com

Send Grahame an e-mail and fire your questions at him,he will probably even sell you a small quantity to experiment with.

Barry,Have you used those muscle wires much? I've been having a look online and haven't had much luck finding the specifications of the wire, i.e. what voltage will cause it to contract and how much a length of it will contract relative to it's length at room temperature.

Is it right that you have to first stretch it by 5% and it will then return to it's prior length when a voltage runs through it.

It should work quite well to raise and lower one of the smaller guns on the tank. The only problem is the wire will need to be fairly short and probably wont allow for much movement.

[Guest]

Thanks Barry. I just found this online too, has lots of info about muscle wire, aka, smart wire, memory wire etc.

http://www.tep.org.uk/FMimages/Smart%20materials/sma%20booklet.pdf

[wonwinglo]

Fascinating stuff this wire,well worth some experiments,that makes for interesting reading.

Thanks Barry. I just found this online too, has lots of info about muscle wire, aka, smart wire, memory wire etc.http://www.tep.org.uk/FMimages/Smart...%20booklet.pdf