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The RS-550 is early and pretty crude.  By the end of Samhongsa's reign as the king of 3-rail O gauge brass, they had moved on to the RS-555 (which at least has five poles.)  These were still mass-produced, low cost motors.  If you can find another one you might get lucky in that it might just happen to be "better."  And there's always the DynaXorb!

bob2 posted:

I am not anti-flywheel.  They are truly nice if properly balanced and you have room.

Joe had a vibration problem.  I think it is that horribly balanced Williams flywheel.  He thinks it is the motor.

There is an easy way to find out, and it is not by running the motor in your hand.

I truly wish I had known that before re-motoring my Williams "J" and losing its original motor.  Even with an 8000 Pittman it is painfully slow.  Nice model, though.

8000’s are awfully small motors Bob.....I’ve never repowered a Williams J.....is there no room for the 9’s? .......my Williams Niagara   I’d think I could put a starter motor in there.....it’s cavernous.......Pat

I just glanced at RS555 motors. It appears that the RS555SA is a high speed model. One seller claimed 8,000 rpm at 12v. No other seller claimed that.

I even found a new one with ball bearings however that one only said 5 or 6,000 rpm at 12v.

I would keep looking closer for what would be a replacement if I can't get a better sealed Pittman motor.

I'm thinking a RS555 with ball bearings and a gear change might be the cure as a back-up plan.

Engineer-Joe posted:

I just glanced at RS555 motors. It appears that the RS555SA is a high speed model. One seller claimed 8,000 rpm at 12v. No other seller claimed that.

I even found a new one with ball bearings however that one only said 5 or 6,000 rpm at 12v.

I would keep looking closer for what would be a replacement if I can't get a better sealed Pittman motor.

I'm thinking a RS555 with ball bearings and a gear change might be the cure as a back-up plan.

Correct Joe, I’m thinking along the same lines as you, not sure if you seen one of my replies, I’ve got one model of Pittman ( 9433 ) that’s a ball bearing motor.....I think it might fit the bill....I passed along all of this info for my buddy at AMETEK, to see what he thinks......I’d just like to make sure it can turn the RPM you need to make some descent speed and not spin itself apart....I think anything you put in that loco with the existing the gear box is going to need ball bearings........that was my first thought......Pat

Engineer-Joe posted:

I may be wrong here, but I think I either need a 12v version or a 24v that spins real fast at 12v??

I can imagine that the MTH PS2 board puts out more to spin it faster at top voltage but I'm only guessing?

12 volt Joe, there isn’t going to be a 24 volt that’ll crank up in time to meet that gearbox....if there was, it’d be such an amp hog, the system would lay down before you got going......Pat...

So you have not yet tried the entire mechanism without the flywheel?  Will you put a different motor in there and drive this flywheel?  That would be an equally valid test of the flywheel.  If it is smooth, then I get to eat that crow.

Don't forget - that anemic little high speed motor probably went to triple its normal rpm when you held it in your hand.  It was screaming like a JT8D probably.

bob2 posted:

So you have not yet tried the entire mechanism without the flywheel?  Will you put a different motor in there and drive this flywheel?  That would be an equally valid test of the flywheel.  If it is smooth, then I get to eat that crow.

Don't forget - that anemic little high speed motor probably went to triple its normal rpm when you held it in your hand.  It was screaming like a JT8D probably.

I answered this above and didn't direct the answer to you properly. It didn't run abnormally high because I only put 8 volts DC to it. I don't have another motor that fits the drive. Mine have gears on them. The engine is back together. I already snapped off the whistle by accident and am upset.

I will test it and make a video just for you, the very next time I take it apart. I'll just have to rig something up just for that test to replace the flywheel drive to u-joint assembly. Tubing would need to be multiples slid over each other. So it would fit the motor shaft on one end and a square protrusion out the other or fit over the whole 2nd u-joint at the gear tower.

You make it sound easier to do than it is.

Last edited by Engineer-Joe

Thanks.  It isn't trivial, but some Toyota#O hose will probably fit over that square slip joint.  Yes,  you will have to increase the diameter of the motor shaft - maybe some model aircraft fuel line?

Your original question was regearing - my original answer was yes, I regeared a W Challenger.  Much, much easier to do my proposed test first -

you might like to avoid the really difficult gear installation stuff.  It involves pressing, knurling (you need a lathe) and quartering, plus modifying the motor mount, etc., and in the end if you really want a flywheel it complicates the project considerably.

I have several Williams models - the PRR Turbine, a Mike, a PRR T1, and three of those really neat B6 switchers.  All have that cheap Chinese motor, and all run quite well.  The "J" was an anomaly.  I think it is "hit or miss" with these things.  But I assure you, the gears themselves are robust, and should not be changed.

I saved the gearboxes from the W Challenger.  I will probably use them some day.

 

Ok Joe, I’ll post on here what I’ve found out from my buddy from Ametek........I told him what’s going on, and we need a high revving motor for these Williams with the stock gearboxes....of course he has off the shelf motors he’d be glad to sell, but they’re up in the stratosphere as far as cost goes nowadays, so I had him look at a part number of one in particular I have here that I thought might work out ....part number 9433L382 this is a ball bearing equipped, fully sealed Pittman designed for medical equipment....( by part #) book says this motor will do 7700 RPM all day long....most Pittmans run out at 6K.......I have a good handful of 9433L382’s in hand,......my buddy said this motor should have no problems 8-9K as this particular model # is built with a lot of overkill for the medical industry.....so, one of two ways we can do the test, either I can stick one in my Williams Niagara, and see what it does, or just shoot one to you, and let you have at it.....no harm, no foul to try it out....shouldn’t be that bad of a swap......lemme know, I’m game either way......” this is a test of the emergency Pittman network, this is only a test.....”beeeeeeeeeeeeeeep”....................Pat

Yes, I would like to buy it from you Pat. My email is in my profile and I sent you one just now.

Bob2, I have to ask why you did re-gear it then? More top speed?

I will try to remove the flywheel for fun. I still need something to tell the PS2 tach how fast the motor is spinning.

Maybe I can put a plastic disk against the gear tower to lesson the vibration? If the motor had dual shafts, I could install it behind the motor like MTH does.

Last edited by Engineer-Joe

I re- geared it for Carl Phillips.  I told him not to, but he wanted to do it.  That’s when I learned about the newer NWSL case distortion.

Pat - I have had motor discussions before. In a nutshell -

I used the 9434 Pittman almost exclusively for my first ten or so scratchbuilts.  With the 24:1gearboxes they were ok.  I forget when, but sometime in the mid ‘90’s I got my hands on an 8424. I was so pleased with the smaller size and higher rpm I never looked back. At one point I was ordering them by the box directly from Pittman.  My motors are always rare earth, ball bearing, and silver graphite.

One of the locals was ordering the 9236 with 7 1/2 volt specs. He said it worked fine at 12-14 volts.  

Even the 12 Volt 8000 motor is not fast enough for the Williams gearbox. If you put a 12 Volt 9000 series motor in there your Challenger will smoothly crawl out of the yard heading for about 30 mph top speed.

Awaiting your results. I will try not to inject too many more opinions here - but if you haven’t tried the 8424 with Toyota hose and a long shaft 653-6 gearbox you are truly missing something.

Last edited by bob2
bob2 posted:

I re- geared it for Carl Phillips.  I told him not to, but he wanted to do it.  That’s when I learned about the newer NWSL case distortion.

Pat - I have had motor discussions before. In a nutshell -

I used the 9434 Pittman almost exclusively for my first ten or so scratchbuilts.  With the 24:1gearboxes they were ok.  I forget when, but sometime in the mid ‘90’s I got my hands on an 8424. I was so pleased with the smaller size and higher rpm I never looked back. At one point I was ordering them by the box directly from Pittman.  My motors are always rare earth, ball bearing, and silver graphite.

One of the locals was ordering the 9236 with 7 1/2 volt specs. He said it worked fine at 12-14 volts.  

Even the 12 Volt 8000 motor is not fast enough for the Williams gearbox. If you put a 12 Volt 9000 series motor in there your Challenger will smoothly crawl out of the yard heading for about 30 mph top speed.

Awaiting your results. I will try not to inject too many more opinions here - but if you haven’t tried the 8424 with Toyota hose and a long shaft 653-6 gearbox you are truly missing something.

You’re not getting any argument from me Bob, everything you say, makes perfect sense.....hopefully, this 9433L382 can crank out some RPM’s ....nothing beats a try but a fail....😉........I’ve checked these specs against other 9433’s and 9434’s.....it has a higher RPM rate....I have a bunch of 8300’s & 8400’s that don’t turn as high as your 8424...that’s a well set up motor....Joe should be able to do a simple test with this motor....I’m sending him one for a trial...........Pat

Well, for some reason I hate to post this right now. I am tired and quit for the evening, so here's where I'm at.

Bob2 was right for the most part so far. I had to drill out the stock flywheel for the new Pittman motor shaft diameter. I didn't get it perfect. The flywheel wobbles on the shaft. At high RPMs it's real loud. Took a quick file to it and it smoothed out ever so slightly. Just not good enough.

 I removed the flywheel altogether. I put a hose from the motor shaft, over a smaller hose piece on it, and connected it to a piece of square plastic stock filed down slid into the U-joint. It was real quiet apart on the bench at slow speeds. I had to have something for the tach to read so I made up a semi-hollow flywheel for the tach tape. I put it together and test ran it. I swear it's every bit as loud as before I started. It didn't go over around 45MPH no matter what I tried. It maybe the poorly striped & wobbly homemade flywheel adding to this issue.

 I've had this engine apart at least 10 times tonight. I gave up on it and will have to figure out what's next. This contraption of mine has to spin so fast and hard to get the engine to track speed that it sounds like it's tearing itself apart. The more I think about it, the solution is to change the gearing.

 So I'm really back where I started or worse. Now some things are done that I can't undo. I hate to have another scrap engine laying around. Either I gut this for parts for my broken 2 rail Allegheny (needs the PS2 board set) and add to the pile, or figure out some way to keep the rpms lower. 

The next time I feel like trying stuff, I'll look into the gear box. Way over my skill set but what do I have to loose? I wonder if the MTH gearbox would fit?

BTW I stuffed the inside of the shell with some foam double sided tape. I thought it might help. It didn't. 

Joe, I'd look for a new flywheel sized for the Pittman motor and see if you can bring sanity back to the mix.

Another option, if the running characteristics with no flywheel isn't objectionable, consider a much lighter flywheel, less mass to vibrate at high speed.  Anything round like a model car wheel with a flat tread could be pressed into service for the tach tape.

gunrunnerjohn posted:

Joe, I'd look for a new flywheel sized for the Pittman motor and see if you can bring sanity back to the mix.

Another option, if the running characteristics with no flywheel isn't objectionable, consider a much lighter flywheel, less mass to vibrate at high speed.  Anything round like a model car wheel with a flat tread could be pressed into service for the tach tape.

John, I made a flywheel out of hollow plastic cap. It isn't the main source of the noise. It adds to it at the insane rpm. Just the wind noise of anything spinning at that rpm is high. I took the flywheel out of the picture and the mechanism is still loud. It makes me want to look closer at how my MTH steamers run so quietly.

The original flywheel mounted to the stock motor was not out of balance. I'm quite sure of that, even more so now than ever.

I removed the flywheel altogether. I put a hose from the motor shaft, over a smaller hose piece on it, and connected it to a piece of square plastic stock filed down slid into the U-joint. It was real quiet apart on the bench at slow speeds.

How was it at high speeds in this configuration?  If just as noisy at high speeds without flywheel or plastic cup, then I get to eat crow.

Joe, it IS possible to make the 44:1 gearbox quiet(er) at 45 mph.  No Pittman is going to work with this gearbox.  The flywheel helps to protect the mechanism and keep things moving over dirty track, etc.

IMO what you need is a new Mabuchi RS555 rated for 12000 or 15000 RPM.  A new, BALANCED flywheel with at least two opposing set screws to affix it to the shaft.  (I would order one for a Lionel steam loco that has a Canon or Mabuchi motor, like the Atlantic or Ten Wheeler.)  Tighten each screw a little at a time to get it centered on the shaft.  Some further balancing may be required.

Mount the motor in rubber grommets if you haven't done so already.  You should be able to find these at the hardware store.  And for gosh sakes install the DynaXorb!  It's a sound attenuator, that's what it's made for!  It's not that expensive, and you can easily peel it off it if it doesn't work.

Bottom line, with the 44:1 gearbox, Williams got the hard part right.  But they used a cheap motor, an unbalanced flywheel installation, and -- brass.  Great for musical instruments (until they get dented from careless handling.)  IMO die-cast is better for trains.  I'll take my chances with zinc pest.  Some of you probably have an MTH Premier 0-6-0.  Guess what?  Almost the same gear range, including a 12000-rpm motor.  It's just better balanced, and the die-cast body mutes the sound rather than amplifying it, hence my recommendation to use DynaXorb.  If your loco were die-cast, we wouldn't be having this conversation, and everyone would be marvelling over the smooth slow-speed operation possible with a properly-geared loco.

Last edited by Ted S

If you are sure it is the gears, I would be happy to knurl the axle and requarter for you.  But gears whine - any noise from a worm gear setup other than a whine is probably due to looseness between gearbox and axle.  To test for that, just hold the gearbox with your fingers while on the test stand.

I have a four speed in my ancient convertible Mustang.  No vibration when a gear speed is exceeded.

Pittmans are usually well balanced for rotation at rated rpm.

So I greased and oiled everything inside. This hose will eventually fall out at higher speeds so I have to hold a guide to keep the hose aligned.

So here it is Bob2! The original flywheel was not wobbling like everyone insists it was. It's now ruined for this job. So it has to be replaced.

The engine is way louder on the rails as the bench's foam is absorbing most of the sounds. I finally learned that the gear tower adjustment is how deep the worm goes into the axle gear. I thought it was an adjustment for the angle to the motor to keep the u-joints straighter.

The motor is mounted with the stock rubber grommet and now with double sided foam under the mount itself.

The Pittman I got only went half speed. It had a much thicker shaft too. I liked it but not so much for the slower speeds. Maybe 45MPH max down hill with the wind. I'd need one that is twice as fast I believe.

A good hose will not require stabilization. Try it with two segments, or a longer shaft?

So are you telling me I have to eat crow?  That it is your gears that are noisy, and not the flywheel?  My iPad says it sounds like a normal mechanism, but then my ears are about as good as an iPad speaker.

Machining a really good flywheel is child’s play for a machinist.  I would make you one, but shipping would eat you alive.

No sir! Don't eat crow. It is quieter without a flywheel, I agree. It gets loud at track speeds no matter what. I have to have a flywheel for the tach.

 I took apart the gear tower and used a lube kit that I have. The gear oil in there seems to bind it up a bit. I then used what grease I had and even some oil. Someone posted about reversing something so I looked inside the gear tower to see how it worked.

 Right now she's all back together. I put the stock flywheel back on over some heat shrink on the motor shaft. It wobbled so I took a file to it.

 I also played with the worm gear angle and depth without much difference in noise. The mechanism screams so loud with the stock motor and flywheel, I just can't tell what's the worse culprit.

 I don't know if any of this makes sense. I'm tired of going backwards here. I don't have a lath. A plastic flywheel spinning at 10,000 RPM would be loud. It would be worse if it wasn't balanced right.

 I don't think getting another motor at 10,000 rpm would really help. It's just geared too low. 30MPH seems to be top speed for this engine. I could have kept the Pittman in there but at 30MPH, it really doesn't matter. I might restripe the flywheel so that it thinks it's going faster. That might be the best cure all here. I could tell the grandkids " Look it says it's doing track speed!"

In the olden days we used straight DC for power.  No tach required.  But if you absolutely have to have the magic, send me a chunk of plastic and dimensions.  Try for dimensionally stable plastic, like aged Delrin.  Shipping for that is probably three bucks - handleable.

Machining will have to be on a mandrel for concentricity.  I have really good American made collets, and two ancient American lathes.

Small flywheels aren't much better than no flywheel at all.  My MTH 20-3020 doesn't coast worth a darn, really most of my PS1s don't.  A flywheel's diameter, and especially its mass at the rim is key to its ability to store energy.  High RPMs help a lot too.  If he does go with a smaller flywheel, he might be a customer for the super-capacitor keep alive discussed on the other thread!

New theory: The motor bearing on the flywheel side has worn (from the action of the unbalanced flywheel, and lack of lubrication), and that's much of what  you're hearing.  Thus Joe should try another high-speed Mabuchi motor.  For all the time invested so far, and especially if he has more Williams locos in his collection, I would want to have a spare lying around.

By the way Joe, I see that green plaid lining the firebox  and crown sheet .  Nice try but double-sided foam tape isn't DynaXorb!  Don't give up!!

So.....

on another post that I clouded up, pictures were posted of changing out the worm gear to get a good drive(?) out of a gear box.

half way down:

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Not knowing what I had, I went inside. The problem here is that the gear box tower inside this Challenger, reduces the drive by a factor of 8 1/2 times, if I counted correctly. That means the motor has to spin 8 1/2 times faster to get the wheels to spin at a given speed. ( if I explained that correctly.)

No wonder this thing is cranking out some huge RPMs.

DSC_1240DSC_1241

So it's not the worm gear here. It seems to have a decent angle (Spare MTH shaft in the pic top right, I ordered for another engine).

It's the gear reduction tower causing the huge RPM required.

So............... maybe a direct belt drive??

Maybe swap out the top shaft and add belt pulleys to each?

Upper shaft diameter is .120" (3mm)

lower is slightly thinner .117"?

Something replacing this tower?

What's next, I don't know.

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Last edited by Engineer-Joe

Joe what is the final drive ratio ?  16:1,  20:1  40:1 ???    What is the number of motor revolutions to turn the drive wheels one turn ?    Some of Williams locos were made by Ajin and use a different gearbox than the Samhongsa locos. I suspect this loco may have the infamous 44:1 box.  Ultimately the front and rear drivers must have the same final drive ratio.  If it is above 40:1 no 500 series Mabuchi is going to run quiet enough to please you at anything above 30smph.  Closed case motors like the Pittman motors run very quiet but don't have enough revs to acheve much more than 30smph.  I have been wondering how a 9V or even a 6V Pittman would preform with those high ratio gear-boxes.  Using the voltage to rate a motor is a poor practice but is the most common system. A better way to rate motors is the static resistance. For a given motor frame the lower the static resistance the higher the RPM will be at any given voltage.  Higher RPMs call for lower static resistance and with that comes higher current pull. All the 500 series Mabuchi motors that were used in these Williams locos that I have measured had a static resistance between .90 and 1.1 ohms. Those motors even running with no load at all pull close to three amps. Stall them and that jumps to 12A !! Which will fry most motor driver boards. Clearly these things are not designed for TMCC or DCS digital control.  Only Train America Studios made a 15A driver board capable of surviving a stall with one of those beasts.  I have used Lionel driver boards in one of those 42:1 Williams locos with a 550 motor and they have great pulling power thus are unlikely to stall and fry the board however they make far too much noise at a scale 50mph and pull enough current to ruin pickup rollers and the center rail of your layout.  I put a Mabuchi 385 in my Williams PRR L1s Mikado and ran it over at my brothers house two weeks ago. We had it pulling 27 cars at around 50smph with little problem. It runs a bit warmer than a Pittman but the Pittman won't run more than about 35smph.  Joe the 21:1 and the 42:1 gearbox used in the Williams Samhongsa as well as the Weaver brass are easily swapped however the gearbox in your loco would be very hard to swap or change ratios without original Samhongsa parts.  I have emailed you a link to the Mabuchi 385 motor that I used in the PRR L1 Mikado 12000rpm no load 2 ohm static resistance and 6A stall @12v. I also sent a second link to a 385  10000rpm no load @12v a little cooler running at 3 ohms static resistance and 4A stall @12v.  If I were doing it again I might opt for this slightly slower/cooler motor. To touch on the Pittman motors again a 9v Pittman may have enough rpm ??? but would have a shorter duty cycle you may have to stop and cool down every now and then.   Closed case motors just run warmer for a given static resistance but are a must if noise is a factor or they are used in an explosive or corrosive environment.   The Pittman motors are a bit pricy to do much experimenting but the 385 Mabuchies are cheap enough to play around a bit.  Getting a flywheel mounted and RUNNING TRUE is likely to be your biggest problem.              j

I still think you guys are looking at this differently than I am. I'm sure you understand me. I just think you've decided to run it as is.

I truly believe the gearbox needs to be addressed. Yes I know that's not possible, right?

Why ask a motor to scream that high?

So... what if.....??? I put two pulleys on custom shafts and have the motor turn the lower worm at 1:1 ratios? I think 4:1 would be better but I'll have to see what kind of pulleys I can get to work with a given belt. Anything lower would be better than this 8.5:1 that's inside here.

Maybe a stock Third Rail belt set-up would work here? I've seen the inside of my Sunset Allegheny and I think the belt system would work if I can set it up correctly. Then, I'd leave the worm to axle gear alone, and pull out the tower's idlers as they won't be used.

Last edited by Engineer-Joe

A blast from the past?  On page 1 I explained that I did one for Carl Phillips (rip).

I have never used tower gearboxes.  The extra idler gear is another source of noise, and the gearbox shows.  I am not going to look up the part number, so this part number is only for the 1/4" axle, and the Williams needs a metric size.

I used two metric axle equivalents of the NWSL Mod O.6 part 653-6, one with a wor m shaft long enough to extend from the rear cylinder front face all the way to within 1/4" of the motor shaft.  I used a pittman 8534 motor (ball bearings, silver graphite brushes), and Toyota #0 hose between motor and rear shaft.

K&S tubing is used to make shaft size compatible with the hose.  Easy to solder.

Between engines I use Speedometer cable with a square slip-joint.

The newer NWSL gear cases need to be adjusted to ensure proper mesh.

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