Piko Motor Chirp

[TempLayout]

Hello all.

I've got a few Piko American Steam locos that all (some worse than others) make a weird chirping sound a the lower end of the RPM range. It's not much of a electronic hum or buzz (frequency), but more of a very quickly repeated mechanical squeak type of chirping. It's definitely based on the RPM of the shaft. In doing some maintenance recently I've pulled one of them entirely apart to give it a thorough cleaning/refurbishing. That model in particular wasn't running/looking too great after having been in storage for about 4 years or so. It is the Santa Fe Freight Train Starter Set #37104 0-6-0 loco which has the simpler running gear and no bearings. It is not the newer R/C Version. Years back I decided to go DCC and I bought and installed the Piko American Steam DCC Sound Kit and the recommended Visaton speaker for it. Overall it works great.

Just the other day, I cleaned up everything and tore down the whole motor block and cleaned out all the old grease and electrical contacts. I took out the motor and put just a tiny drop of R/C Electric motor oil that I've been using on R/C Cars for a while on the ends of the shaft on either side of the can. Then I hooked the motor up to some DC power and let it run a bit. It quieted down quite a but. Long story not quite as long, I built it all back up and when running it, the sound persists and it's pretty loud. I'm sure with the volume turned up it would be far less noticeable but it is absolutely present. I'm curious if it may have something to do with the frequencies in the Decoder CV settings or not. I don't think so. I'm pretty convinced it's a mechanical issue with the bearings or lack thereof (possibly brass bushings) on the motor shaft. My gut says it just needs more oil, but I REALLY don't want to put a bunch on oil on the motor... 100% spells trouble in my mind. I'm very in the "less is more" line of thinking. Maybe it's just the way it is?

My other Pikos make this same sound too and both of the following have ball bearing motor blocks:
Piko 38210 D&RGW Rio Grande 2-6-0 Mogul Steam #218 (Piko American Steam DCC/Sound added by me)
Piko 38141 B&O 0-6-0 Digital Starter Set #95 (Came with the Decoder stuff installed)

I have a camel back and another mogul that I haven't been able to get to recently that I'd like to check. Too much stuff out and they are tucked far away in a corner of storage.

On the other hand, my DC (non-DCC) LGB 2076 D DR Steam 0-4-0 I got for my 5th birthday that is nearly 40 years old, also was recently taken apart and built back up in the exact same care/style as I did the Piko and wow. That thing runs and slides along the rails as smooth/quiet as a well maintained high end sewing machine! And it's seen some hard use and multi decade storage cycles. The pikos run pretty well, they just make chirping sounds and I prefer they didn't. Mechanical squeaks like that tell me something's not right/done well. Who makes the motors for Piko? Can I buy a better one from some other supplier? It has to be a stock motor type/shape/style... just the shaft and worm gear might be the biggest hurdle.

 

[notofthiscenturyTim]

Hello all.

I've got a few Piko American Steam locos that all (some worse than others) make a weird chirping sound a the lower end of the RPM range. It's not much of a electronic hum or buzz (frequency), but more of a very quickly repeated mechanical squeak type of chirping. It's definitely based on the RPM of the shaft. In doing some maintenance recently I've pulled one of them entirely apart to give it a thorough cleaning/refurbishing. That model in particular wasn't running/looking too great after having been in storage for about 4 years or so. It is the Santa Fe Freight Train Starter Set #37104 0-6-0 loco which has the simpler running gear and no bearings. It is not the newer R/C Version. Years back I decided to go DCC and I bought and installed the Piko American Steam DCC Sound Kit and the recommended Visaton speaker for it. Overall it works great.

Just the other day, I cleaned up everything and tore down the whole motor block and cleaned out all the old grease and electrical contacts. I took out the motor and put just a tiny drop of R/C Electric motor oil that I've been using on R/C Cars for a while on the ends of the shaft on either side of the can. Then I hooked the motor up to some DC power and let it run a bit. It quieted down quite a but. Long story not quite as long, I built it all back up and when running it, the sound persists and it's pretty loud. I'm sure with the volume turned up it would be far less noticeable but it is absolutely present. I'm curious if it may have something to do with the frequencies in the Decoder CV settings or not. I don't think so. I'm pretty convinced it's a mechanical issue with the bearings or lack thereof (possibly brass bushings) on the motor shaft. My gut says it just needs more oil, but I REALLY don't want to put a bunch on oil on the motor... 100% spells trouble in my mind. I'm very in the "less is more" line of thinking. Maybe it's just the way it is?

My other Pikos make this same sound too and both of the following have ball bearing motor blocks:
Piko 38210 D&RGW Rio Grande 2-6-0 Mogul Steam #218 (Piko American Steam DCC/Sound added by me)
Piko 38141 B&O 0-6-0 Digital Starter Set #95 (Came with the Decoder stuff installed)

I have a camel back and another mogul that I haven't been able to get to recently that I'd like to check. Too much stuff out and they are tucked far away in a corner of storage.

On the other hand, my DC (non-DCC) LGB 2076 D DR Steam 0-4-0 I got for my 5th birthday that is nearly 40 years old, also was recently taken apart and built back up in the exact same care/style as I did the Piko and wow. That thing runs and slides along the rails as smooth/quiet as a well maintained high end sewing machine! And it's seen some hard use and multi decade storage cycles. The pikos run pretty well, they just make chirping sounds and I prefer they didn't. Mechanical squeaks like that tell me something's not right/done well. Who makes the motors for Piko? Can I buy a better one from some other supplier? It has to be a stock motor type/shape/style... just the shaft and worm gear might be the biggest hurdle.

I can't comment on the specific locos or decoder, but I have found that different decoder Pulse Width Modulation frequency settings can affect the noises produced by a motor.
For one loco I have (a twin motor Piko BR 218) the PWM frequency caused audible hum at low speeds. I increased the PWM frequency setting and the hum went away completely. There is a potential risk of overheating with very high frequencies so proceed with caution.
There may be a decoder CV setting which you can change and see if it improves things. Many modern decoders use 16khz as default which is higher than some older models.

 

[TempLayout]

I can't comment on the specific locos or decoder, but I have found that different decoder Pulse Width Modulation frequency settings can affect the noises produced by a motor.
For one loco I have (a twin motor Piko BR 218) the PWM frequency caused audible hum at low speeds. I increased the PWM frequency setting and the hum went away completely. There is a potential risk of overheating with very high frequencies so proceed with caution.
There may be a decoder CV setting which you can change and see if it improves things. Many modern decoders use 16khz as default which is higher than some older models.

Tim thanks for the comments and apologies for the late reply. Crazy last couple weeks came up unexpectedly, as unplanned events do.

It doesn't seem to be that sort of an electrically induced noise. My gut feeling is it's mechanical. I haven't been able to run much lately since I rebuilt the little Santa Fe starter. I'll run it a bit more and report back on if the eclectic motor oil seems to have made any difference on the bushings on the shaft. I'm hopping that it'll work it's way around the squeaky bits and quiet down.

 

[TempLayout]

So I still haven't been able to do much of any running the locos on the layout... however, I did get a set of test rollers and put a tiny dab of electric motor oil from my RC kit just on the bushing/bearing point where the motor shaft protrudes from the can on each side.

I put one loco, the Piko 38141 B&O 0-6-0 Digital Starter Set #95 (Came with the Decoder stuff installed), on the rollers and the squeak/chirp was present in both forward and reverse. I let it run forward slow, as the sound is most pronounced at slow speeds. Keep in mind I have adjusted the CVs for speeds so it's top end is less than factory default, but I have not adjusted any of the more advanced CVs relating to PWM/EMF or anything like that. Just top speed, acceleration, braking... things like that.

I run my locos in 28 speed steps typically. I let this one run for about 10-15 minutes. It quieted down a tiny bit. Then I ran it backwards at about speed step 3 and the chirp was pretty noisy. I let it run in reverse at speed step 3 for a while, about 2 hours or so and the chirp quieted down to nearly nothing. Speed it up, slowed it down, both reverse and it was quiet. Then ran forward and the chirp was still present and pretty noisy. It is currently running forward at speed step 1 and has been for about 15 minutes and hasn't made any changes yet, but I'll update with more info after it has been running for a while.

All evidence though seems so far to point to just a mechanical "squeaky-wheel" as it were. I'm now assuming that the motors don't have ball bearings, but rather a brass friction bearing/bushing on the shafts. I guess that it probably pretty common. That is what seems to make the most sense to me. I just wanted to post this while it was on my mind and I had a brief moment to do so and not leave this thread hanging in the wind.

 

[dunnyrail]

So I still haven't been able to do much of any running the locos on the layout... however, I did get a set of test rollers and put a tiny dab of electric motor oil from my RC kit just on the bushing/bearing point where the motor shaft protrudes from the can on each side.

I put one loco, the Piko 38141 B&O 0-6-0 Digital Starter Set #95 (Came with the Decoder stuff installed), on the rollers and the squeak/chirp was present in both forward and reverse. I let it run forward slow, as the sound is most pronounced at slow speeds. Keep in mind I have adjusted the CVs for speeds so it's top end is less than factory default, but I have not adjusted any of the more advanced CVs relating to PWM/EMF or anything like that. Just top speed, acceleration, braking... things like that.

I run my locos in 28 speed steps typically. I let this one run for about 10-15 minutes. It quieted down a tiny bit. Then I ran it backwards at about speed step 3 and the chirp was pretty noisy. I let it run in reverse at speed step 3 for a while, about 2 hours or so and the chirp quieted down to nearly nothing. Speed it up, slowed it down, both reverse and it was quiet. Then ran forward and the chirp was still present and pretty noisy. It is currently running forward at speed step 1 and has been for about 15 minutes and hasn't made any changes yet, but I'll update with more info after it has been running for a while.

All evidence though seems so far to point to just a mechanical "squeaky-wheel" as it were. I'm now assuming that the motors don't have ball bearings, but rather a brass friction bearing/bushing on the shafts. I guess that it probably pretty common. That is what seems to make the most sense to me. I just wanted to post this while it was on my mind and I had a brief moment to do so and not leave this thread hanging in the wind.

Oh that brings to memory an annoying squeek made by collection plungers mentioned somewhere. The solution was a small application of LGB 50010 Smoke and Cleaning with a cotton bud to clean the rear of wheels where the plunger passes over.

 

[TempLayout]

Oh that brings to memory an annoying squeek made by collection plungers mentioned somewhere. The solution was a small application of LGB 50010 Smoke and Cleaning with a cotton bud to clean the rear of wheels where the plunger passes over.

Oh yeah that's a good thing to consider for other locos I've got in the maintenance lineup. My little LGB 2076 D DR Steam 0-4-0 has those pickup plungers. It was making some noise and I tore it down and cleaned everything up. It runs so amazingly smooth now. I never thought that the plungers could have been making noise, but it/they very may well have. When it was all apart, I scrubbed the wheels with the smoke/cleaning fluid on cotton bore cleaning patches, including the backside of the flanges the plungers rub against. They were quite dirty after 38 years. After having cleaned all the gunk off, I polished them with some 5000 grit micromesh polish pads under running water. Worked pretty well.

These piko moguls and little tank engines don't have any plungers. Rather they have copper strips that are sprung against the ball bearings of the front and rear drivers, which no movement between them takes place, or at least there shouldn't be.

The loco that I had running yesterday for a while quieted down significantly. It's pretty much silent in reverse, but still had a bit of chirp/squeaking going forward. I opened it up and added another micro drop of the RC Electric Motor Oil to each bushing and put it back on the test rollers. It's running again now at varied speeds for a bit and has gotten significantly quieter. Almost silent now.

I assume that the oil and with just further running it will eventually just come to a nice broken in point.

 

[TempLayout]

Here's a pic of the Piko internals for those interested. This is the motor block that all the American Moguls/Tank Engines are using that have ball bearings on the front and rear drivers.

This is from the Piko G-Scale 38141 B&O Baltimore & Ohio Digital Starter Set (circa 2017)

 

[dunnyrail]

Ah so the pickup is in the inside on those bearings, my comments about using LGB Smoke Fluid to possibly reduce an irritating squeak or chirping could equally apply to those bearings as well.