Tail-end (new) wagon problem

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HobbitFertang

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Hi Folks, happy Easter one and all! I've just acquired a very nice new RhB dump wagon (LGB 46696). I was dismayed to find it derailed every time at four locations on the layout when pulled around behind a RhB loco and passenger carriage. I wondered if the bogies needed adjusting or some weight needed to be added (?). Then, after messing around with the track alignments for a couple of hours to attempt a solution (no other bogie carriages or wagons having had a problem btw), I tried adding another wagon to the back of the dumper . . . and hey presto it was absolutely fine everywhere:):):). Is this 'tail-end Charley' effect recognised or is there a problem with the track or the wagon?? PS my track is fairly steep and winding :confused:
 

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It's a long wheel base wagon on twisty track. Could be the wheels, bogies or the track itself.

Maybe the extra weight of dragging another car helps to stabilise it, but I would check the other things I mentioned too....
 
Do the axles spin freely?
As there some 'slop' in the pivot? - This acts as 'suspension' keeping the wheels in contact with the track.
Is something catching, so the rear is not straightening up?

PhilP.
 
HobbitFertang said:
Hi Folks, happy Easter one and all! I've just acquired a very nice new RhB dump wagon (LGB 46696). I was dismayed to find it derailed every time at four locations on the layout when pulled around behind a RhB loco and passenger carriage. I wondered if the bogies needed adjusting or some weight needed to be added (?). Then, after messing around with the track alignments for a couple of hours to attempt a solution (no other bogie carriages or wagons having had a problem btw), I tried adding another wagon to the back of the dumper . . . and hey presto it was absolutely fine everywhere:):):). Is this 'tail-end Charley' effect recognised or is there a problem with the track or the wagon?? PS my track is fairly steep and winding :confused:
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Bogies can do funny things.

If, as you say, there are gradient changes, is there sufficient front-to-back rocking on the bogie? Is it possible to slacken off the bogie mounting screw a tad?

Or, does the bogie touch a bit of the wagon at the wrong moment?

Obviously, lube the bogie pivot and the axle bearings - axles need a bit of sideways movement within the bogies - don't ask me why, but I have Accucraft US bogie stock with slightly finer wheel flanges and, if there is ever a rare derailment, I've often found that lubrication of the axle bearings solved the issue.
 
Yes, the amount of bogie pivot (seems quite a lot) is as it came out of the box. Yes, the bogie does foul the body if the tilt is sufficient, but that seems the case on all my carriages/wagons (?). So I guess the answer lies in the track geometry to solve that one.
 
HobbitFertang said:
Yes, the amount of bogie pivot (seems quite a lot) is as it came out of the box. Yes, the bogie does foul the body if the tilt is sufficient, but that seems the case on all my carriages/wagons (?). So I guess the answer lies in the track geometry to solve that one.
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I am the UK's expert in badly laid track - as in rough, and as I said, I also have quite a few Accucraft US wagons with finer flanges than Bachmann, and much finer flanges than LGB.

However, I don't have sudden changes of gradient - life is quite gentle here in Norfolk ;)

If it is track related, then get your head down to track level and watch the wagon traverse the troublesome spot - this should reveal the problem, although you may need three or four passes before you spot it.

I'm still 75% wagon problem 25% track - but then again, I'm frequently wrong as SWMBO points out :devil:
 
Thus far the wheels have not been fully covered, how is the back to back measurement? Should be the same on all wheels thus the one causing the derailment could be out.

I like to have as little side to side movement as possible within the axle guards and to this end fill the gaps with M3 nylon washers (ref 190-215) I used to get them from Squires at Bognor. I get them in packs if 100 that go a good way. But Ebay will supply if Squires cant at around £5 per hundred.

Also a tiny splash of LGB 50l19 lube (other brands will also be mentioned in here) on both the axle bearings and pivot may help.

Most of the above already mentioned, do you have hooks on couplings both ends? All of my stock does with no hooks on the loco but the loco couplings dropped down by 20-30 thou. This has given me very reliable running with very rare uncoupling or derailment problems.
 
Yes, I do have couplings at both ends but I've not applied any oil. Is any light oil OK, for example my hair clippers oil? (they're not worked very hard these days:confused:). The back to back on the wheels is 40 mm and the axle guard gap is about 1 mm each side. Btw are the hoppers (two each side) intended to actually work (with coarse sand maybe?), or would that cause damage, the assemblies being all plastic.
 
HobbitFertang said:
Yes, I do have couplings at both ends but I've not applied any oil. Is any light oil OK, for example my hair clippers oil? (they're not worked very hard these days:confused:). The back to back on the wheels is 40 mm and the axle guard gap is about 1 mm each side. Btw are the hoppers (two each side) intended to actually work (with coarse sand maybe?), or would that cause damage, the assemblies being all plastic.
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Be careful with oil - I'd only use one of the model railway hobby oils - Jon has mentioned LGB's offering, there's Hobb-e-lube, with Bachmann and Peco also making model oils - it's a question as to which of those is easiest to obtain. These model oils don't attack plastic while some other oils (3-in-1 is notorious) do.

Now back to the issue - basic, silly question. Have you turned the wagon around and run it the other end first?

Back-to-back sounds OK.

Is it only this hopper wagon, or does another one do it as well?

Do the hopper wagons have a longer wheelbase than your other LGB wagons/coaches?

Lots of questions :whew::whew::whew::whew:
 
Rhino has cautioned very correctly about oil. As for loose loads, well sand could be an issue but any loose load as a normal can be a real pain if you get a derailment. If you want good looking loads make up an insert to the wagon, then you can glue a load to that. If the insert is a loose fit loads cane be added and removed to represent loaded one way empty the other as I do on my line. I have referred to loose loading before and it can be a real pain even with a so called working loading plant, dampness can get in sand even ballast to cause real issues.

However I have used my LGB ballast wagons to place ballast on my line, but this is a rare thing only enjoyed a few times when ballasting taking place.
 
Don't try to 'sand' your track!
No matter how fine, those grains of sand are 22.5 times bigger to our models..

Sand in oil, is a great grinding-paste, and will destroy plastic 'bearings'.

PhilP.
 
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Yes, the wagon weighs 1.16kg and has a (relatively) long wheelbase so maybe the bogies move about a bit more than say the long RhB passenger coaches (with which I've had no trouble). Maybe I'll try some weight in the hopper or some lead under the chassis. The bogie pivot to pivot distance on the wagon is 310 mm whereas on the passenger coach (LGB 30510) its 428 mm. The weight of the coach is 2.28 kg so the wagon is pretty much half the weight but roughly two thirds the wheelbase of the coach. I have tried turning the wagon around and the problem seems to lie mainly with whichever bogie is at the rear. I've only got the one hopper wagon so nothing with which to compare. I get the feeling it's a weight distribution thing as most of the structure sits in the middle of the wagon. With any other vehicle hooked on the back the problem disappears. The photo show that the wagon's coupling 'arm' (top) is only slightly shorter than that of the passenger coach (bottom).
 

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Mmmmmmm .............................. OK. Time to experiment.

Firstly, I think you need to get your head down :p:p and work out what, how and where it's derailing. Try to see which axle comes of the rails at which point.

As an experiment, how about inserting a thin washer under the bogie pivot - a plate (penny) washer would probably prevent the wagon from wobbling - but see whether that solves the issue. Could it be that the coupling arm is fouling the buffer beam?

I have an Accucraft brass long caboose which has a couple of penny washers under the bogie mounts - it needs a little extra height because when the bogies move excessively on my rough track, being a brass model, it can short out, causing the train to stop dead o_O The washers solved the issue and the difference in ride height is not noticeable even with body mounted couplers.

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HobbitFertang said:
my track is fairly steep and winding
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i think there lies the problem, not in the wagon.

do these four derailment places happen to be where a curve follows a straight? (or a straight follows a curve)
do you use R1 curves?
do the derailments occur where the track changes elevation or inclination?

given, that you use bogie mounted hook and loop:
if you can answer one of these questions with yes, maybe some strategic placed guardrails could help.
 
Ah, yes I'm increasingly getting the feeling that my track is poorly laid out in places with mainly R1 curves and sharp changes in gradient:sweating: in order to achieve 3.5 degree inclines, compared with what I've seen on the forum. I've tinkered at length with spacers tucked under the track which does work, but not in every case. I also have a recognised issue with some R1 points not lying perfectly flat (twisted). Come to think of it parts of the layout look more like a roller coaster than a railway:giggle:. Btw has anyone thought of building a G-scale roller coaster?? . . . . .Oh also, has LGB/Marklin ever considered doing UK stuff?? That would be awesome would it not!!
 
HobbitFertang said:
Ah, yes I'm increasingly getting the feeling that my track is poorly laid out in places with mainly R1 curves and sharp changes in gradient:sweating: in order to achieve 3.5 degree inclines, compared with what I've seen on the forum. I've tinkered at length with spacers tucked under the track which does work, but not in every case. I also have a recognised issue with some R1 points not lying perfectly flat (twisted). Come to think of it parts of the layout look more like a roller coaster than a railway:giggle:. Btw has anyone thought of building a G-scale roller coaster?? . . . . .Oh also, has LGB/Marklin ever considered doing UK stuff?? That would be awesome would it not!!
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Gotta be careful here, or we'll be posting pictures of my track's worse than yours :rofl::rofl::rofl:
 
One mistake I made initially was using stubby off-cuts of track to bodge the correct alignment geometry on curves. These end up distorting and ultimately coming apart as the joiners alone have too much give where the track's not bolted down.
 
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