Help in Identifying 3v DC Motor

[nichukabra]

Hi all,

I'll start off by apologizing for my lack of knowledge on the subject of electronics but I need your help.

I am looking for a replacement DC motor that came out of a miniature face massager. Upon inspection of the motor, I could not find any specifications on it in order to buy the replacement.

Could anyone advise me on the tests that I have to do in order to get some specifications of it? I have a multi meter in my possession along with a spare 3.7v, 135 mAh, 0.50Wh battery that is used to provide power.

I should probably note that the motor does not have much physical resistance while rotating it by hand (unlike the motors of the same size found in RC cars/drones).

I appreciate any help/guidance that I can get in determining what this thing is so that I can find a replacement.

Photo attached

 

[JimB]

There is probably not much that you can sensibly test with a multimeter on a motor in isolation like that.

However, as the motor was powered by a 3v (ish) battery, go to EBay and search for 3v DC motor and you will find lots of them.
These types of motors are popular in the model making world.

JimB

 

[rjenkinsgb]

Motors like that are often specified by the body length, the diameter across the curved sides and sometimes the thickness across the flats.
Plus the external shaft diameter and length, typically 1, 1.5 or 2mm diameter for moderate size motors.

There are dozens of sizes and it's not possible to tell from the photo what size it is?

eg. a " 1220" would be 12mm diameter and 20mm long, an "1824" 18mm diameter & 24mm long etc.

 

[nichukabra]

Hey JimB,

Thanks for your response.

I've looked at eBay and yes I did find lots of them. Except I don't know how to make sure these motors that I'm seeing don't have the strong physical resistance while being rotated by hand.

The reason I'm focusing on the resistance so much is because I went down to a local electronics repair shop and they provided me with a replacement motor but could not be as easily rotated by hand (I later found out it was meant for an RC car).

When I installed it back into the massager, it really struggled to move and would cut out upon the slightest resistance (imagine gently touching the spinning shaft with your finger). The original motor would not only spin slower but also didn't cut out upon touching - it would just slow down.

I am located in a country that lacks any form of professionalism or interest in DIY activities which is why I can't simply go to another repair shop to ask for advice.

 

[nichukabra]

Motors like that are often specified by the body length, the diameter across the curved sides and sometimes the thickness across the flats.
Plus the external shaft diameter and length, typically 1, 1.5 or 2mm diameter for moderate size motors.

There are dozens of sizes and it's not possible to tell from the photo what size it is?

eg. a " 1220" would be 12mm diameter and 20mm long, an "1824" 18mm diameter & 24mm long etc.

Hey rjenkinsgb,

I knew I was forgetting something.

The thickness across the flats is: 12mm
Diameter across the curved sides: 15mm
The length of it is: 26mm
Diameter of shaft: 1.5mm

It's worth noting that this is a brushed motor.

 

[rjenkinsgb]

OK, this is the nearest I have managed to find so far:
**broken link removed**

Edit - another version:

Pardon our interruption...

(There are apparently different voltage rather versions of the "FF-050SH" type motor; the second is rated for a lower voltage so has a higher speed at the maximum voltage show).

 

[nichukabra]

OK, this is the nearest I have managed to find so far:
**broken link removed**

Thanks rjenkinsgb,

Is it a big issue that the input voltage on the motor is 5-6V? The battery that I've got is only a 3.7V.

 

[rjenkinsgb]

Sorry, I must have edited the previous post while you were writing that - a lower voltage type now added.

 

[nichukabra]

Ah great, thanks for that!

I guess I'll go ahead and order that one and hope for the best.

Is there any way to determine how easy this motor is to spin by hand? If I find the datasheet for the FF-050SH for example?

 

[rjenkinsgb]

Is there any way to determine how easy this motor is to spin by hand?

Not that I can think of, it's not something that is relevant in most applications.

In general, I'd guess that a lower current rated motor will turn easier and they are quite low rated.

The one for such as an RC car that you mentioned earlier is probably much higher current and may take too much for the battery supply in your device, so appear to be lower power.

 

[nichukabra]

Great, thanks for the explanation.

I've placed the order and will hope that it works as expected.

Thanks for your help!