Large Scale Central

Aristo RS3 riding up on frogs?

Problem Solving
#13

Thanks Richard, I was focusing on something else, the different motor blocks and their incarnations in the RS-3.

The RS-3 has the reputation for being finicky on track, as the articulation of the motor blocks is limited, many people removing one of the bolsters to sort of make a “3 point suspension” as is often recommended for rolling stock.

I did update my post above a bit, and recently I was running mine, which has the Aristo stainless steel wheel motor blocks, and those have reduced flange depths and mine was derailing quite a bit. Swapping the trucks so that the “flexible axle” was on the outer ends, as opposed to nearest the fuel tank made a huge difference. I had a cross level issue that my other locomotives took in stride, but the RS-3 with the more rigid motor blocks with reduced flanges did not like.

Greg

#14

update:

I have the old style trucks with the axle tips.

I took the RS3 back out to run it through one of the known trouble spots and it passed through just fine at different speeds. I then took it to a another switch and the rear truck rode up and derailed.

I then took just a wheel set, made sure it matched the width of the RS3 wheels and carefully ran it through the LGB 16000 RH switch. I think what is happening is that the longer wheel base of this aristo truck which is approx 4" compared to a USAT at 3.5 is pushing the wheels to the Left rail on the switch as the engine is going through the Right tangent. Pushing the single wheel set at the same width as the RS3 wheels through the switch had the right wheel contact the brown plastic guide opposite the frog, causing it to lift and try to go straight when it should be going right and derailing.

This is a new development. The USAT engines go through Ok. The Aristo B unit with the same wheel spacing goes through ok.

It must be a really fine adjustment that needs to be made by pushing the wheels out a bit so when the truck jogs to the left due to the forward momentum the right wheel will not contact that plastic guide.

#15

My RS3 is a PITA to run so it’s been years since I’ve run it. I think it has to do with the side frames and the way they interact with the axle.

#16

OK, if the wheelset has the back to back correctly set (not yet satisfied), then perhaps the flangeways are not right, but it sounds like your back to back is still too tight, just like the first illustration I posted.

37 and 38 mm are out of nmra spec… you want to be at 40 mm… actually the target value is 40.005 mm

Greg

#17

The back to back is 36mm on the RS3. I measured 3 types of metal wheels on my rolling stock, a Bachmann Climax a NW2 and they are 37mm. The RS3 is tighter than the average but my USAT GP38 which also has a longer truck wheelbase like the RS3 is also 36mm. The wheels on the GP are smaller in diameter but they also have the deeper flanges.

What is weird is that all the wheels on the RS3 have this 36mm and it ran fine over all these switches last month. I don’t know what has changed.

Now to figure out how to remove these axles and spread the wheels a mm or 2.

#18

Todd you don’t have to remove any thing but you should find a Harbor Freight and buy a caliper under $20 from them and 2 straight screw drivers that are the same and will fit between the back of wheel and motor block.

Richard

#19

That’s in my opinion a little dangerous, as you can “cock” the axle in the “gear castings”…

Richard, when you do this, you are pulling against one wheel and this can (not will) produce undue pressure in the wrong places.

Todd, please set the back to back to possibly at the NMRA minimum… your unmodified switches are a bit “sloppy” on the flangeway widths, but you CLEARLY have an out of spec problem.

This page has the specs, and the references to the NMRA and G1MRA standards.

https://elmassian.com/index.php/large-scale-train-main-page/track-aamp-switches/track-and-wheel-standards

Greg

#20

I still think this is really odd how this engine has been fine all last season running over LGB and Aristo switches without issue and now it is having problems wit the LGB ones of all things. Maybe when I open up the motor block to spread those wheels I will find a axle issue but all 4 wheel sets measure the same on the back to back so I don’t think it is a cracked gear problem unless all 4 are broken which is unlikely.

I still do not know what has changed to make this RS3 such a problem except it has the lowest flanges of the fleet.

Thanks for all the info Guys.

#21

Not cracked gear likely, just slowly things change/wear and now you are at the point it is a problem.

Yes, the “lower” the flange height, the easier to “climb out” of a switch.

Also you can check where the “floppy” axles are, the loco will run better with them outboard nearest the ends of the loco, but wiring is a bit tight, and loco will run in reverse (simple matter in DCC to change)…

I have the (short-lived production) Aristo stainless steel wheels, which had “small flanges” and it does derail much more easily.

Greg

#22

Todd Haskins said:

I still think this is really odd how this engine has been fine all last season running over LGB and Aristo switches without issue and now it is having problems wit the LGB ones of all things. Maybe when I open up the motor block to spread those wheels I will find a axle issue but all 4 wheel sets measure the same on the back to back so I don’t think it is a cracked gear problem unless all 4 are broken which is unlikely.

I still do not know what has changed to make this RS3 such a problem except it has the lowest flanges of the fleet.

Thanks for all the info Guys.

Yes, it is odd and frustrating when suddenly a problem exists with no readily obvious cause. Something changed just enough to take a borderline issue past the line into being a problem. It could be temperature (thermal expansion/contraction), humidity/moisture, level of the track, frog casting shifting in the switch slightly, phase of the moon, changes in the gravitational constant, or the locomotive was just bored and wanted to torque you off.

As for all the gears cracked, they were on my USA F3, but that is a different animal, and like Greg said, its probably not your issue.

The thing I take away from this thread, and several others, is that properly gauging the wheels on our equipment doesn’t rate high on the priority lists of some folks. I had many phantom derailments during the first 2 years of my railroad. It was frustrating, and since I wasn’t enjoying my railroad, I wasn’t running it as often as I could have. I finally made a wheel gauge and started checking and re gauging the wheels on my equipment. The difference was like night and day. Suddenly the 12 car freight train, with a USA F3 leading, would run for hours without an issue. Before checking and setting the wheel gauge on the rolling stock, one or 2 go arounds on the railroad with that same train, and something would derail.

There is no point in agonizing over switch flange-way spacing, width and depth, without having properly gauged the wheels on the equipment rolling through that switch. The same can be said about any track-work. Track and wheels are a system, and both have to be within specs for them to operate together properly.

#23

I have three Aristo RS3’s. A 2005 version, sourced from a UK dealer and the other two direct from Aristo (they were the MILW MWLSTS Show engines, the show was cancelled.)

I rarely get derailments particularly on switches but when I do the first thing i do is to look at the ballast and smooth it out ensuring the switch or track is as I feel it should be. That always works for me.

For whatever reason an irregularity in the ballast/substrate causing a lateral movement, will cause me a derailment issue. I have never checked track or wheel gauge or messed around with the motor fearing that could raise more problems. One thing a long time garden railroader taught me, when I first built my railroad, was that locos don’t usually mind a ‘up and down’ movement but a lateral movement was ‘unhealthy’.

#24

Todd,

When problems like this arise, I often find that it is the track at the opposite end of the engine/railcar that has become tweaked and this manifests itself through the body to the other truck. My AristoCraft streamliners are notorious for this and when they continually derail, I look to the opposite corner for track correction.

Another thing to check is the flatness of the turnout itself. If you look at Greg’s picture…, yes you see a wheel riding up. But you also see that the other wheel is all the way over as far as it can be. If the turnout is tilted just a bit, that opposing wheel may come closer to the guard rail and the other wheel may not ride up the frog. The AristoCraft 10-foot turnouts are notorious for this.

#25

It is certainly true that a crooked uneven switch can cause problems and I think it is compounded by the less forgiving shallow flanges found on the RS3.

I do have a picky Piko curved switch that I bought used and had to repair and wheel gauge has to be correct for anything going over that one. The funny thing was the RS3 wasn’t having a problem on that one but several LGB ones instead.

Anyways I took apart one truck and tapped the wheels using my vice to a better gauge from the 36 to 39, repeated this on the other truck and put it back together.

I just tested it running it over several switches and it ran well with no problems.

It is odd how this issue where 4 axles suddenly went out of gauge popped up but now it is all good.

Thanks guys.

#26

Are your trains stored in a warm place, or are they subject to freezing and thaw cycles? In boxes or standing on their wheels?

Perhaps an axle froze quicker than the wheels and they moved laterally. Not a lot each year, until it mattered this year…

I can imagineer 'most anything…(https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-wink.gif)

#27

Todd, you keep mentioning all the locos have the same back to back. Yep they are ALL WRONG from the factory.

This just means you are probably riding on the hairy edge of problems with other locos.

The most important improvement I made in my reliability was re-gauging all my locos and cars… then I worked on the switches… went from 7 car trains derailing and could not be backed up to 50 car trains that will run for hours.

Greg

#28

Greg Elmassian said:

The most important improvement I made in my reliability was re-gauging all my locos and cars…

Greg

Yup, I said the same thing.

#29

Greg Elmassian said:

Todd, you keep mentioning all the locos have the same back to back. Yep they are ALL WRONG from the factory.

Greg

Well that is crazy. Why would they build them like that ?

I have been outdoors with these trains since 07 and never had a problem with engines from Bachmann, LGB and USAT running over nearly 600’ of LGB, USAT and Aristo track and switches. I have had some gauge issues with a few pieces of rolling stock here and there that was easily fixed.

This RS3 took me by surprise that it went out of gauge and all 4 axles were the same. I just think it is odd.

#30

Based on discussion, I just went out and measured the gauge on my RS-3. Based on the Kadee coupler gauge, all four wheel sets are undergauge.

When one side sits in the gauge “slot,” the other side doesn’t quite reach its slot. All four are just about the same.

Probably helps them better negotiate AristoCraft’s undergauge curve sections, a few of which I have. My USA trains do not like these sections and slow a bit as the track tightens around the wheels. In a couple places, I’ve actually filed a bit of the inner sides of the railhead for more clearance.

#31

Long ago on a site recently forgotten, JJ (whom I haven’t seen or heard from in over a year) described cutting a notch in the end of a C clamp to go around an axle. The pad on the screw end pushes the axle back through the wheel thus adjusting the gauge. Go to far and prudent planning reveals a C clamp large enough to reverse the axle/ process when one needs to Undo.

Greg E. probably has a pic somewhere, I know he asked to do it…

edit, found a pic…

#32

Todd H, I can answer your question, and it’s all about deep flanges, manufacturing tolerances , and cost to build.

LGB started it and USAT and Aristo folllowed.

Since everyone started by copying LGB with track that could interchange, the issue continues. Been this way forever, but starts to show up on longer trains, and switches, and when you try to back a train.

Also long story on truck mounted couplers, overly deep flanges, etc.

Track and wheels and gauge and flangeways are a system, and all need to work together. What comes from the factory can be greatly improved, but you normally cannot just change one part of the system without changing the other part.

You can make things work a lot better by following the “target values” in the NMRA specs, but you will find that the switch flangeways will need some shimming to bring them to specification.

If you do this all, everything works a lot better.

Yes, you have been running fine for a while, but over time things can change/wear/move.

I’m only recommending what I know will work, and make things better.

Greg