RC India

hello guys
i just got 4 pairs of props from a local shop
i had a few of 5030s before which were very smooth and had excellent fitting
this motor was 3045 so i thought i should buy it as the props had ringsets
i put the props on the motors without the appropriate ring set [ whatever you call them] and the copter went mad
it was going to break the ceiling at 25% throttle ??? it didnt even lift off at 25% throttle with the 5030s :headscratch:
are my props not balanced cause they do look like they are and most of the companies now a days balance them and ship...
SO my question for all the experts is what is the importance of the proper size of the center hole and why are ringsets so important
and is this one of the symptoms of the centre hole as it is not fixing as well as the 5030s and is a bit loose or is it a fault of balancing of props
thanks in advance :hatsoff:

Higher pitch of prop will increase agility of copter so better continue 5x3 props till you get some confidence.

The ringset as you call it (I assume you mean the plastic rings that come with the props) are meant to ensure that the props have a tight fit on the shaft. I'm not sure how you were able to fit them without it but you should use whichever ring (adapter) fits the shaft the closest. Unbalanced props just cause vibrations, this is probably not even related. Which motors are you using?
 
And what Dharmik Sir said is true but I think it should not make as much of a difference as you are experiencing

agree with SK1701. you must use proper adaptor supplied with prop to fit with motor shaft. in the case of pitch angle it might give you different feel of flying. with 5x3 your quad will climb 3inch per rotation while with 5x4.5 it will climb at the rate of 4.5 inch per rotation(assuming throttle rate is same in both case).

sorry it was a typing error .. the quad lifted at  35% throttle
the prop just fit inside the motor shaft
SK1701 i am using rcx 2400kv motors on my quad
but still dharmik sir the quad when it lifts .. it keeps on gaining altitude even if no throttle is applied
quite confusingg .. it shouldnt do this
the 5030s never did this :headscratch: ???

From what I saw of the motor data, the prop adapter shaft is 5mm. Use the 5mm ring in the props. Could you post a picture of the props and whatever plastic adapters came with it?
When you say it gains altitude you mean that the quad climbs even when the throttle is kept constant? You could deal with this by setting a throttle curve on your radio that is flatter around the point at which the quad hovers. I would, however, suggest you practice move the throttle in very fine increments so it gets ingrained in muscle memory. This is essentially a racer, so the less you rely on software features the better.

Darshan,
A 5045 prop is significantly larger than a 5030 in terms of load on motor and thrust potential.
For example, a GWS HD 5x4.3 will produce 280gms thrust at 15000rpm, as compared to 200gms from a GWS HD 5x3 at the same rpm. That is a 40% increase!
(Source flybrushless.com)

So your 5x4.5s are probably putting out 50% more power than the 5x3s.
That is one issue.

The second is whether your props are balanced. If you don't have a prop balancer, try to find a dowel that fits the prop hole (ballpen refill, plastic straw, jhaadu teeli, anything that fits). Rest it on two glasses or katoris of equal height. Add tape around the leading edge of the lighter blade. There is more to balancing, but this is reasonable start.

The third issue is whether the props are centered on the shaft. For this use one of the several spacers that come with the prop. Usually you will be able to find one whose outer dia matches the prop, and the inner dia matches the shaft.

The fourth issue is whether the new props will overload your motor/ESC/battery.
That cannot be answered as we don't know the details...

In general, please
1. Describe your problem clearly (not like it hit the ceiling ;D)
2. Provide specs of the equipment being used.
This will help you get specifics solutions rather than tukkas from guys like me trying to help!
Regards.

Kk Iyer sir as I had mentioned before the copter just keeps gaining altitude even if I am not increasing throttle
For your first question my issue is that what if I want it to hover at a lower height (near to the ground ) ... I can understand that that's 40%more but still it shouldn't go out of control at that throttle position
For your last question
I am using rcx  1804 2400kv motors with 12a escs and 1500mah 20-30c  3s lipo battery
By hitting the ceiling I mean rapid rise in height which is not control able and if you try to decrease throttle the copter rapidly descends mostly banging into the floor hard

My iPad battery low! Will respond further tomorrow morning. Bye till then.

reduce P gain on yaw and change I gain accordingly. if problem still persists you will have to tinker with other gain settings and tx as well.

It means that you are holding too much throttle!

I saw a test showing that the RCX 1804 2400kv with a 5030 will have about 290gms thrust on full throttle. With 4 motors that is over 1100gms. How much does your quad weigh?

Usually if the weight, motors, props are properly matched, it should just be lifting off at around half throttle. But with the 5045 the lift may be much more than the weight even at half throttle. The solution is simple - use less throttle!
Open the throttle from idle SLOWLY till it starts showing signs of lifting. One or two clicks more will enable liftoff. Remember that you need to modulate the throttle. Even a few gms more thrust than weight will make it climb, and a few gms less will make it come down. Throttle needs constant TINY adjustments to maintain height, especially at low height, as ground effect varies with height.

Try as above before fiddling with settings. If you have a wattmeter, check the amps draw of a single motor at full throttle with the 5045. If it is more than the rated max (6-8amps?) the motor may overheat and burn. Then you may go back to 5030, or reduce lipo from 3s to 2s.

Edit: just saw that in reply #4 you said "it keeps on gaining altitude even if no throttle is applied"
Does it really fly off when the throttle is at idle?  ;D

my quad lifts off at 45~50% throttle and does nice hover but with 5045 nowhere do i see a good hover it just ...uggghhh
and yes sir the motors get hot even with 5030  ???  do i need to change my lipo ??
and sir you know what i mean from "it keeps on gaining altitude even if no throttle is applied"

http://www.rcindia.org/electric-planes/why-does-a-motor-burn-out/msg227353/#msg227353

May be true here too!
Did you try a 2s with the 5045? To compare with 5030 on 3s?