Needs suggestions: Bachmann 2-8-0 derailing at switch

[DigitalGriffin]

Subject says it all.  The front lead truck keep derailing on a PECO curved turnout. 

The joints are smooth.  And the track well within gauge at all points using the NMRA gauge.  I think it's model SL-87.  And the curves look to be within R18"

[rrinker]

 Wheels are probbaly not in gauge.

Or the lead truck is not freely swiveling. If that loco has a sprign on the lead truck, it might be too stiff, causing the truck to puch too hard against the flanges on a curve. WHere is it derailing? Is it picking the frog point, or elsewhere?

                                --Randy

[DigitalGriffin]

rrinker

 Wheels are probbaly not in gauge.

Or the lead truck is not freely swiveling. If that loco has a sprign on the lead truck, it might be too stiff, causing the truck to puch too hard against the flanges on a curve. WHere is it derailing? Is it picking the frog point, or elsewhere?

                                --Randy

 

The points are held against the stock rail by a tortoise.  The lead truck comes off near the frog, and then the first drivers comes off soon after.

The lead truck has no weight on it or spring. (That's the way Bachmann designed it)

[richg1998]

Yours might be an older version. I just looked at the Bachmann Parts page and I see a strip of metal between the truck and frame that is a spring.

http://www.bachmanntrains.com/home-usa/dwg/dwgs/H836-IS001.PDF

If the wheels are in gauge then you will have to add weight.

Edit. They sell the spring for $0.60.

Rich

[ATLANTIC CENTRAL]

richg1998

Yours might be an older version. I just looked at the Bachmann Parts page and I see a strip of metal between the truck and frame that is a spring.

http://www.bachmanntrains.com/home-usa/dwg/dwgs/H836-IS001.PDF

If the wheels are in gauge then you will have to add weight.

Edit. They sell the spring for $0.60.

Rich

 

I took those springs off all eight of my Spectrum 2-8-0's, they pull better and track better without it.

What about the check gauge at the frog? Are the flanges possible hitting the frog, not being pulled over by the guard rail?

Sheldon

[selector]

I sometimes break out my trusty hand-held/makeup mirror when what I'm looking at isn't immediately determinable.  If I can't figure out what's going wrong on a turnout with several slow runs at the problem area, I often get a better, or more complete, picture by placing a mirror behind the rolling stock and watching again...and again...until it suddenly becomes apparent what the problem really is. 

It's most often the lead driver that has the problem, initially, in turnouts, but if your engine truck is doing the derailing, then it isn't being kept clear by the guard or it is out of gauge, or it can't swivel all it needs in order to run the flanges safely through.  One other possibility is that you have either a hump or a sag within a couple of inches of the frog, even if it's just barely enough to let the flanges ride up unhindered by the rail tops.

When all else fails, I enter the Sheldon Mine.  There's gold in there.

[floridaflyer]

Agree with Selector on the hump thing. Replaced a turnout for the same problem  only to find the new one did the same thing. Checked for a rise or hump and wala. leveled the turnout and all is well. Did a bunch if unnecessary work though.

[dknelson]

Pilot trucks are also sensitive to slight variations in flat level for a turnout, so a bullseye type bubble level pushed along the track through the turnout might well reveal that the turnout needs a bit of shimming; hopefully nothing more serious than that.

The old trick of wrapping some solder around the axle of the pilot truck might give it the heft it needs to prevent these derailments.  At the very least it is a "fix" which is easy to undo.

Dave Nelson

[DigitalGriffin]

Thanks for the tips guys.  I'll try a few and if I still have issues I'll post a movie.

[dstarr]

DigitalGriffin

The points are held against the stock rail by a tortoise.  The lead truck comes off near the frog, and then the first drivers comes off soon after.

The lead truck has no weight on it or spring. (That's the way Bachmann designed it)

Sounds like the pilot wheels and/or the drivers are banging the frog right on the nose.  The wing rail on the stock rail side of the turnout is supposed to press against the back to the flanges and pull the wheel set toward the stock rail and away from the frog.  There is a stud on the NMRA gauge to check wing rail positioning.  If the wing rail is too close to the frog, the fix is to superglue a thin strip of styrene to the stock rail side of the wing rail. 

   Any steamer will benefit from as much weight as you can fix onto the pilot truck.  I have a Spectrum 2-8-0 and it works just fine thru all my turnouts.  If it only derails on this one turnout, I would certainly suspect the turnout.  But checking the locomotive is also a reasonable thing to do. 

[rrebell]

Had a slight problem with a Shinohara turnout once, was a slight rise in the frog area that occured in manufacture, just took a very fine file and filed the whoile frog area that of course just filed down the rise as I stopped once it hit the other rails.

[Autonerd]

I just bot a Bachmann Mogul and noticed that even though the lead truck appeared to be firmly on the rails, the wheels weren't always turning. Removed the truck, bent it down slightly, and now its making contact. Haven't had it out on the mainline yet.

[richg1998]

I just searched the Bachmann HO forum and users here are not alone with the pilot truck issue.

Some might check the forum out for this loco. Usually a very good loco.

Rich

[markie97]

If its a Peco code 100 turnout you may have to shim the guard rails. I ended up doing it on all my Peco code 100 turnouts as some(not all) of my equipment would derail at these points. I used .01 plastic to do the shimming.

[wjstix]

Take a look at the connection between the locomotive and the tender. Bachmann engines normally have an apron that folds down to connect the cab and tender. The tender deck (facing the engine) has a protruding 'lip' that the apron sits on. It's easy to put the engine on the track with the apron getting stuck under the lip. That pushes the rear of the engine down, and the front up - which can sometimes result in the lead truck or even drivers derailing.

When putting the engine on the track, I usually fold the apron all the way up against the back of the cab, get the engine on the track, and then use a small screwdriver, pencil, etc. to reach in between the engine and tender to pull the apron down.

[rrebell]

Brought to mind another problem I found. Sometimes the wires from engine to tender dose not allow enough slack do to being put together slightly wrong at the factory, there was always plenty of wire but when they put the tender shell on they did not allow enough to stick out.

[xdford]

I have had an issue or two with Peco turnouts although they are usually very good. I have found that the wheels can pick the lead into the frog and/or the guard rails. I have very slightly bent the lead of the guard rails and fairly well stopped the issue.

As others have pointed out, the frog can also warp upwards almost imperceptibly.  I have used a block and a light tap back to level with a hammer where it was bowing. It is more than likely due to expansion problems which I should not have so much of as my layout has moved from a garage to inside with a house move...

Good Luck from Australia

Trevor