Bachmann Online Forum

Discussion Boards => HO => Topic started by: Billm10454 on October 17, 2012, 02:40:28 PM

Title: Noise for acela passenger cars
Post by: Billm10454 on October 17, 2012, 02:40:28 PM
When I run my Acela I hear a noise that can be described as brakes sqeeling. Anyone no what is is. It only comes from the passenger cars. The cars roll freely. Is it possible that it comes from the pickups that rub against the wheels?
Title: Re: Noise for acela passenger cars
Post by: MilwaukeeRoadfan261 on October 17, 2012, 03:02:38 PM
Either that or the axles in the trucks. I used to get that sound from the tenders of my Bachmann steam engines and all it took to get rid of that sound was just a touch of plastic compatible oil like Bachmann light gear oil where the axle meets the truck assembly.
Title: Re: Noise for acela passenger cars
Post by: jonathan on October 18, 2012, 06:30:16 AM
I just did a little tinkering with my acela train.

That squeal you hear is definitely the resonance caused by the bronze pick up brushes against the backs of the steel wheels.  I liken it to a musical note.  It's a a steady, single note vibration. Think of those thin brushes like a tuning fork that is constantly being agitated.  Hence the squeal is the  same pitch on all the passenger cars, since the brushes are all the same size.

I applied a microscopic drop of conductalube to the back of each wheel on the passenger cars.  The "squeal" went away immediately.  I'm sure as the oil dries out subsequent applications of light oil will be required.

I know nothing of metalurgy (can't even spell it).  However, I suspect the resonance is caused by two different types of metal being forced into a friction-type relationship.  Thankfully the conductalube is a good fix.

I have had this issue with a couple of tender pickup brushes, especially my 2-8-4 Kanawha.  The light oil fixes it as well, albeit temporarily.

Regards,

Jonathan

Title: Re: Noise for acela passenger cars
Post by: Billm10454 on October 18, 2012, 09:50:50 AM
Jonathan described the sound exactly. I will try the lube. Thanks
Title: Re: Noise for acela passenger cars
Post by: Doneldon on October 18, 2012, 03:19:53 PM
He spells "metalurgy" exactly right, too.
Title: Re: Noise for acela passenger cars
Post by: jonathan on October 19, 2012, 06:15:13 AM
Well, thanks!

To follow up on the tuning fork analogy, I wonder if a touch of caulk, somewhere along the pick up brush would deaden the vibration as well.  Will try it at my next opportunity.

Regards,

Jonathan
Title: Re: Noise for acela passenger cars
Post by: WTierce1 on October 19, 2012, 08:52:10 PM
Mine does the same thing, although I kind of like it, it seems to add some realism, but that is just me.