RC India

Gentlemen (Are there any Ladies present in this forum? :headscratch:),

Can someone please suggest a tried and tested way to remove the weights from the Vibra motors found in cellphones?  I have been able to remove one but unfortunately snapped away a portion of the shaft along with it. Don't want to repeat that wonderful feat again!

Regards,

VC

Do you have a dremel or its equivalent with you?

there are two methods for first one you cannot do without dremel but for the second method you can make do with a water grinding stone.

The motor which you broke the shaft also can be used now

I do have a Dremel 300 with all attachments......

First method works will all motors which is as follows

The eccentric weight is thicker at the shaft for half of diameter and thinner at the remaining half diameter. Use dremel to grind the thinner half up to the original shaft. You may have to take help of a magnifying lens and do this delicately. Once you reach the shaft the eccentric weight comes off easily with just your fingers. Don’t worry even if a small bit of the original shaft gets grinded. You will be still able to fix a prop with a micro fine tip and CA glue. (Since eccentric weight requires very less shaft length, you will not get a long shaft in this method though)

The second method works with most motors which are coreless which is as under.

This you can try out with the motor which you have already broken the shaft while trying to remove the eccentric weight. Use your fingers to hold the can of the motor. Yank off the motor shaft from the motor using nose pliers along with the eccentric weight if new. In coreless motors since the core is just plastic former with coil wound on it and the shaft running through it through a bronze bearing it will come out easily with little effort. Measure the shaft dia with a screw gauge if you have it, else or by just visual estimation you can compare it with a safety pin or a sewing needle which has pin of same dia. This you can also try to do by trial and error after cutting pin/needle to make a shaft to the required length and grinding the tip smooth and round on a grinding stone/dremel. Just try to insert the samples which you have into the bronze bearing of the motor. If it is thicker it will not go in and if it is too thin it will be loose and will not fix inside. The correct dia shaft will go in easily in through the bronze bearing and delicately with very little effort will go in through the plastic former and fix inside. (This method you can get a shaft length of desired length)

I like the second method with coreless motor of 4mm motors and even bigger dia 6mm/ 7mm motors very much. Since it gives me a shaft length of required length.

I can show you photos of two motors 6 mm which I have used the second method

The photos of six mm coreless motors modified with a longer shaft to accomodate a 2508 props

The shaft is made using a safety pin of same dia.

Thank you Col. Here we go................

Just one hitch - Where does one get 2508 props in India?

Mr Sai rcforalllin is the man. But of course he is selling as a combo with his GWS 05 and GWS 10 DC brushed motors.  You should check with him if he is still having it now. Or you can always order from www.plantraco.com Canada.

But 2508 will work with 6mm and 7mm coreless but not with 4mm coreless.

Is there an easier way of fabricating such props? I mean, by using scrap plastic etc?

you can fabricate props using material like balsa and scrap plastics but it is all dependant on your fabricating skills. Balancing the prop both aerodynamically as well as in weight is a major prob in such cases.

Since it is not balanced and due to the material used it is not durable enough. Due to lack of availability one can resort to such a practice but not as a regular feature. I have not been successful in making a durable prop till date for a direct drive brushed motor.

However if you are using a micro geared mechanism to reduce the speed of rotation then you can use fabricated larger diameter props with higher pitch which spin slowly.

for gear mechanisms open up a non working cheap china made electronic clock available for Rs 50-100 a piece

small update. The 2508 in direct drive with 6mm in the photos was not giving sufficient pull as the RPM was low. I had to clip the Prop using nail cutter to overall dia of 1.5 inches. Now after the clipping the combination is fine The RPM is also high and giving sufficient pull.

i m getting some 4mm vibra motors from a mobile shop
can u tell me which prop to use with them??
and what weight [of the plan]can they handle each??
plz help me out!!

-ANkur

i got my answer
this prop can be used with vibra motors
http://www.microflight.com/Online-Catalog/Propellers/Micro-Butterfly-Prop