My HO,made in Slovania, IHC, 4-4-0 with DCC and sound, Derails more than any other loco I have. The wheels are in gage and the flange depth is good. If I check the balance front to back, where should it be? It looks like this
ng side. This derailment I can count on. Any thoughts will be appreciated.
Which 4-4-0? The 1870’s model or the one derived from a 20th century SP 2-6-0? A model steam locomotive should (but many do not) balance at a point centered between the first and last driver axles. It is common/normal for the front truck on a model 4-4-0 to be light weight. A light spring is often used to put some pressure on the truck. All IHC 4-4-0s made to date feature deeper than RP25 flanges which work best on code 100 track.
I don’t know which year it is. How much of a difference from the NMRA gage should I be looking for? I just assumed that the newest ones would be RP25.
Is it just the leading truck that derails? If so, remove it and see what it does as it rolls over the frog. Maybe the guard rails are trying to “spread” the wheels, which, of course, ain’t happening. Also, check to make sure the switch components conform to standards.
I would think that your engine has quite a spread between the middle “4”. Could it be that the turnout just is not suited for the distance between the drivers? A tight gauge may want to retain the frame at a certain angle back at the drivers, but the truck wants “more” nearest the frog. Maybe. Could be.
When I encounter a reluctant engine truck, or simply an engine that doesn’t like some part of my track plan, I run it back and forth for as long as it takes, even at dead slow, to find out the first inkling that something is going the wrong way. Often, it is at the frog, but it could be the guards, the wings, the distance between them, the points, a mound under the turnout, a bad hinge if it is a commercial turnout…the list goes on.
Personally, I would be glad of the help that a simple addition of weight would do to solve the problem, but not having discerned the fault in the first place would continue to bother me. Is the frog point in the way of a smooth line from closure to frog rail? Are the guards or wings not gauged right? Is the frog too high, too low?
Bruce, that four largely separated driver stance will be a solid and unyielding/unacommodating platform. If a dip or a rise along any of the major rails forces the truck ahead of the drivers to get airborn, you can imagine how effective even non-RP-25 flanges will be. When I have an intractable truck upon introducing a new engine, I find that my trackwork support is defective and that there is sag someplace that makes a rise somewhere else to compensate. At the rise, the truck is flapping light and will often find its own path.
Then there’s all the things that could be off about the truck. Oy!
I haven’t mastered my camera or photobucket yet. I tried to post a photo of the 4-4-0 I am having trouble with
The photo you added appears to be a Roundhouse 4-4-0, not IHC. The Roundhouse does have RP25 flanges. However, flange size and make are not what is causing your derailments. I would have to check the symptons you list more carefully, but in the end it almost always boils down to problems with the track (at turnouts, and vertical dips and/or horizontal kinks in normal track) and/or the gauge and tracking of the wheels.
For seeing horizontal kinks in track - put your eyeball at rail head level and sight down the track. this makes the kinks a lot more visible.
For vertical dips in track - lay a straight edge along the rail tops and check for daylight between the edge and the rail head. Also, check for rocking - indicates a high spot. Do the same across the rails at turnout frogs.
Use an NMRA gauge to check wheel gauge, and check gauge at turnouts. Make sure the points sit tightly against the stock rails and there is no “bump” where the train would follow the point rail. Finger nails along the inside corner of the rail head are a good detector of anything less than smooth, especially at rail joints.
Pony trucks on small HO engines can be a problem. Try removing it and see how well the engine tracks. The balance point of the engine with the pony truck removed should be between the 2 driver sets, and slightly towards the front driver. You want to use minimum spring force on the pony truck - adding wieght to the truck can reduce the need for spring pressure.
Last caution - the MRC DCC sound decoders used by Athearn and Roundhouse are not the best quality. Some work fine and last a long time; many do not. If the decoder causes trouble, you may be better off replacing it with something else.
Hope this helps.
Fred W
That isnt a IHC engine. That is a Roundhouse MRC Decoder-sound Equippted Athearn 4-4-0.
You need to have good trackwork as it will derail on any flaw. You are challenged by a rigid 4 driver base two of which is probably traction tired equippted. I used Kato Track and didnt have too much tracking problem with it. But it is a very picky engine and ultimately I scrapped it for parts and threw the MRC decoder away.
http://img532.imageshack.us/my.php?image=roundhouse440versiontwocu6.flv
My spring on the front truck were fine. Hit and miss quality control perhaps?
Bruce: I had this exact problem with my Roundhouse 4-4-0 (which is the engine you pictured).I can sympathize with you, because it just about drove me nuts till I figured it out. Problem was just as you described, constant and unpredictable derailment of lead truck.
In my case the spring on the lead truck was at fault, not providing the correct amount of tension. A cone type spring used on the Mantua General 4-4-0 was substituted and the problem was solved. One wheel on my lead truck was slighty out of gauge (too narrow), but correcting it did not cure the problem. Changing the spring did, and since it’s a cheap and easy fix, I would suggest givnig it a try. It definitely wasn’t my track work as I have very reliable operation, and no problems with virtualy every type of 4-4-0 you can think of from the Mantua Belle of the 80s on down. (never met a 4-4-0 I didn’t like)
If you don’t have access to this spring, try Yardbird Trains, who can fix you right up. Great folks, and very reasonable.
If all else fails, send it back to the Athearn Service Center and have them try to correct. Their customer service is very slow, but they will eventually respond.
Hope this helps
JBB
Thanks guys. Of course, it is a Roundhouse. I looked at the wrong box when identifying it. You are all very sharp! I want You to know how much I appreciate all the advice I get here.
I think I will try to add some weight to the pony truck and try a different spring and see what happens.
Belle of the eighties: reminds me of my first 4-4-0. Painted it green and gold. Wish I still had it even if it didn’t pull very well.
B:
Don’t throw it out. In theory, a rigid wheelbase of > 3 wheels can’t make perfect contact. In practice, plenty of model steamers, including all of my own, have rigid wheelbases and work fine. If you’re lifting the wheel enough to clear the .025 RP25 flanges, ya gots track problems, buddy boy, big track problems.
I don’t have this engine, but I do have an MDC 2-6-0, which has an even longer driver separation, and it works fine. Anyway, the point is that the basic design isn’t inherently unsound, and works fine in practice, theory notwithstanding,so the problem certainly is fixable. In other words, don’t throw it out yet.
What I want to know is this: how is the lead truck designed on that? Is it mounted on a long leaf spring, pivoted behind the truck, or slotted, or what?
Do you have any more details? Does it derail more backing up, or going forward? Does it derail at switches, or is it always climbing one or the other rail at curves?
Meanwhile, I’ll leave you with one idea:
(The drawing of the derailment is a little crude, but the general idea is there. Basically, your truck will tend to go diagonal on the rail if the pivot arm is short.)
The extended-pivot arrangement, of course, can never be right for any but one radius. In practice, though, it works fine to fit it to your sharpest radius. The main thing is to keep the rail/wheel angle at a minimum. It doesn’t have to be zero. It never is, for any four wheel truck.
I’ll look at my MDC 2-6-0 and see if I can make it derail the same way, and report on the findings…
The pony truck has a semi circular slot in its center. The spring that came with the loco is conical. I PRESUME the larger end of the spring goes against the truck and the smaller end towards the loco. As well, the semi circle “ends” should be facing rearward. Right?
BB:
Right so far. Still need more info on situations where it derails.
How freely does the truck pivot pin slide in the curved slot? There may be a burr stopping the truck from moving easily.
A closeup shot of the truck would help, and straight-on, of the bottom of the loco.
Not familiar with this engine, but one thought struck me. In your picture there is a pretty good angle between the tender and engine on the drawbar, Is there enough slack to keep tender from trying to pull down on back of engine?
The drawbar angle is an optical illusion. It is parallel with the track.
The pony truch does have a good bit of side resistance, not from a burr but from the conical spring. The underside of the truck has a circle of plastic molded in (on) where the spring is supposed to fit. As the truck moves sideways, the spring skips over this circle and is quite scratchy.
To reiterate, The locos drive wheels derail at the frog of a code 83 curved turnout when entering from the non diverging end and towards the points. It does this both forward and reverse. The drivers both go off to the inside. The pony truck and tender trucks are not affected if I stop the loco when it derails. It does not happen on the diverging route.
The frog is level with the stock rails and I can detect no up or down longitudinally.
???
I run my Roundhouse 4-4-0 with the small end of the spring against the truck. It ended up like that after I installed a keep alive capacitor in the smoke box and reassembled the loco. I run the loco on handlaid code 100 with handlaid turnouts. A few Peco turnouts are also used.
Rich
For the two minutes it would take to find out, I would invert the spring and try again.
Also, if you have a tiny sanding disk a la Dremel, see if you can tidy up any ‘bearing’ surfaces that are gritty. This depends on how “gritty” gritty is. A burr will definitely have to go, but some smoothing will undoubtedly help also. You will probably have to use 600 or 800 grit if possible to get something reasonably smooth, and maybe use a grease film.
Blind Bruce,
I quickly scanned all the post so far and have not seen any note about the wires running from the tender to the locomotive. Check to make sure that the wires are loose and not causing the front of the locmotive to lift just a slight bit to cause derailments, it looks like there might be 4-6 wires there. I had a 2-6-0 that did the same thing and it was caused by the wires between binding just a little, it doesn’t take much.
Barry
When you solve that issue and are really ambitious, here is a link to a site to close couple the engine and tender.
http://www.pacificcoastairlinerr.com/1905/4-4-0_coupling/
A review.
http://www.pacificcoastairlinerr.com/1905/roundhouse_4-4-0_page/
Rich