New PB user with couple issues

[olly_k]

Hi folks - just got my first powerball 250pro this week and have to say these things are pretty addictive
I do however, have issues with NSD! The first powerball I purchased had a knocking sound when in use - despite this I still managed 8500 revs but I sent it back the next day to the guy who I got it from.
He returned a new powerball the next day and this time, there is no knocking, but a small amount of grinding at higher revs... comes and goes but definately there! Still, I have managed 10621 which is better shows either I have improved after two sessions or this ball is MUCH better!

From what I have read I think there is an inherant problem in shipping these units. In my opinion the weakness lies not in the packaging used to ship the item in (Mine was wrapped in bubbles and more bubbles!), but I think, the lack of packaging between rotor and outer shpere? Would it not be possible for NSD to insert some form of protection, with a sort of pull tab attached designed as a one-off shipping solution?
Anyway, it will be interesting to see what others think... I would like to get mine working without the buzz again but I want to have a few days fun with it before I try pulling it apart - I couldn't manage another day without one of these things!

[Adrena1in]

Welcome to the forums!

That's not a bad idea actually, having a pull-strip of some sort which keeps the rotor secured, an unable to knock about when in transit. I've fortunately never had an issue myself, and I've received many new and used Powerballs. But I know what you mean.

About the grinding noise though...was it a new one you got, or a used one? Brand new ones should be silky smooth, right up the rev-range, but after some use the inner tracks will lose their sheen and they will start to sound a bit rough. However, this is usually a good thing, as the rotor axle with "bite" more on the track, and roll more easily. (Plus I find they go faster too!). Perhaps this second one of yours is like that?

Tim.

[olly_k]

Welcome to the forums!

About the grinding noise though...was it a new one you got, or a used one? Brand new ones should be silky smooth, right up the rev-range, but after some use the inner tracks will lose their sheen and they will start to sound a bit rough. However, this is usually a good thing, as the rotor axle with "bite" more on the track, and roll more easily. (Plus I find they go faster too!). Perhaps this second one of yours is like that?

Tim.

Hi Adrena1in, thanks for the reply. The grinding is more like a small distorted sound as the speed hits about 5 or 6k, not always there either and it doesn't remain thru the range. Apart from that it is quite smooth I think!
The guy said he thoroughly tested before shipping and I have no reason not to believe him - it was very well packed too.
The original one knocked about a lot right thru to 8.5 which was the max speed I could hit on it!

[Tstering]

As Adren1in said the grinding isn't necessarily a bad thing. All mine have a slight griniding noise, and infact the one that grinds the most is the one with my top scores on it.

[olly_k]

As Adren1in said the grinding isn't necessarily a bad thing. All mine have a slight griniding noise, and infact the one that grinds the most is the one with my top scores on it.

Fair enough you just expect to get somthing in mint condition when you buy new!

[Adrena1in]

...expect to get somthing in mint condition when you buy new!

I agree.

Plus I also think the noise you're referring to isn't the sort of grinding you get from a well-used Powerball. What you say about it being intermittent makes me think it's more of a vibration than a grinding. Does it sound a little like a mobile phone, on vibrate, ringing on a wooden desk?! I get that occasionally, and I've never really figured out what causes it. It's something to do with some sort of intermittent imbalance. For me, it's always gone away after a while.

[Enda]

Hi Adrena1in, thanks for the reply. The grinding is more like a small distorted sound as the speed hits about 5 or 6k, not always there either and it doesn't remain thru the range. Apart from that it is quite smooth I think!

I think that this is actually similar to the sound which The Force spoke about some months back.

It only occurs in some Powerballs, and is nothing to worry about. Essentially it is the result of harmonics produced when the freely suspended rotor and support-ring spin in the track between the shell halves.

I'll try to find the video and post the link here.

Regards

Enda
--

[Enda]

The thread is here but I'm afraid that the video which donkapone had linked has been removed from his site.

Certainly I'm sure that its a result of resonance though olly_k and as a result not something you need to worry about. It will probably disappear once the new ball is worn in.

[olly_k]

I agree.

Plus I also think the noise you're referring to isn't the sort of grinding you get from a well-used Powerball. What you say about it being intermittent makes me think it's more of a vibration than a grinding. Does it sound a little like a mobile phone, on vibrate, ringing on a wooden desk?! I get that occasionally, and I've never really figured out what causes it. It's something to do with some sort of intermittent imbalance. For me, it's always gone away after a while.

No, but I think I know what you mean - I got that by accidently reversing the thing at low revs it goes into a sort of low freq oscillation. I stopped it as soon as I could as I read it isn't a good idea to reverse these things in motion...?
Maybe it is similar just at higher speeds...

Anyway, these things are seriously addictive, just can't put mine down now although I am having trouble getting to 10k now maybe I need a rest!
I am hoping when my back has strengthened that I will see a difference at my local climbing wall - my weak points were always finger grip and stamina, mainly because I could never be bothered exercising

[Adrena1in]

...I read it isn't a good idea to reverse these things in motion...?

If you mean the direction in which you gyrate your wrist, then it doesn't really matter. Don't do it every few seconds if you can help it, but a change in direction every now and then is fine. I do it often. The worse thing is to spin the Powerball up to speed and then hold it loosely, so it rattles about like crazy.

I am hoping when my back has strengthened that I will see a difference at my local climbing wall.

You wanna speak to Dennis Van Hoof, he's a rock climber. (I was meant to be going to my local climbing wall this evening for a "taster" session, but I'm not now. Shame, was looking forward to it.