Plastic Trucks & Wheels constantly derail

[NewConductor]

Again a newbie question. My old Bachmann set that i bought used, has the rolling stock constantly derailling at the slightest glitch in the track. Is this due to the fact that the trucks & wheels are all made of plastic? i tried to add weight to the cars, but that didn't help either. would heavier trucks/cars & metal wheels adhere better to the rails? how much lateral sway should the trucks have? mine seem to have quite a bit.

TIA.

[jward]

note where things derail, run your trains slowly through that spot, and carefully observe what the wheels are doing. often the wheel flanges will ride the tops of the rails a little way before they derail. where they climb on top the rail, not where they drop to the ties, will be where your problem lies. using an nmra guage, you can go through and fix these spots one by one.

as for the plastic wheels, wheels with rp25 flanges, noticeably smaller than those on the older train set cars, are more important than metal wheels. but most metal replacement wheels, and most new cars, have rp25 wheels.

[electrical whiz kid]

Good trackwork is absolutely neccessary for trouble-free running of trains.  If you take pains to accomplish this, it will be an investment that will pay off greatly.  Don't and you will find yourself pulling your hair out in frustration, and possibly giving a whole new meaning to the term "kit bashing".
As for plastic wheels:  Metal wheels have proven to be a much better alternative, as plastic wheels tend to pick up crud, dust, etc that can accumulate on rails.  I have found them to be subject to axle warping, cracking, and other forms of deterioration, and avoid them like the plague!
.  The most common-RP-25 wheels are readily available from a lot of kit manufacturers, as well as companies more or less dedicated to parts, such as Kadee and Reboxx.  Even if it takes a bit longer because of finances, good track, wheels, and also couplers, are good investments.  Have fun.
Rich

[NewConductor]

thanks the track is not perfect and probably needs some work. my loco goes around full speed at no problems, but will work on that.

thanks Rich, will look into getting some metal rp25 setups.

[jward]

it should be noted that some metal wheelsets with plastic axles, such as kadee, are subject to the same axle warping problems described in the above post. best to look for wheels with metal axles, such as those made by bachmann, jaybee or nwsl.

[Omaha]

One of the most important items that you need is a NMRA gauge. If you have one you can check your wheel spacing, flange size and track spacing. If any of these are out of gauge it will lead to a lot of problems.

[Doneldon]

NewCon-

For reliable tracking you need outstanding track work, proper trucks and wheels, properly installed couplers and the correct weight in your rolling stock.

Track work is primarily a function of careful installation and verifying that the track is within NMRA (National Model Railroad Association) specifications. Potential problem areas are rail joints, curves, the points where curves (both lateral and vertical) begin and end, and turnouts (switches). Make sure that both rails are inside of your rail joiners. Check gauge every foot or so with an NMRA gauge. Ease into curves if you can (not truly possible with sectional track but flex-track makes it easy). Check all of the clearances at turnouts, especially where the points (moving rail tips which direct trains one way or the other) contact their stock rails. Keep your turnouts level and don NOT fasten them down. They'll work better of you allow them to "float."

Use quality trucks. These rarely come with inexpensive models or older models which have not been upgraded. Metal wheels are clearly superior to plastic, as are metal axles, but every kind of wheelset (two wheels and their axle) must be in gauge. Use your NMRA gauge again.

Use quality knuckle couplers, set at the correct height to the car's body. Talgo trucks, which have couplers on beams attached to the trucks, are an inferior design which will not perform well. Kadee couplers are the best available. You can use either standard Kadees or the smaller scale size Kadees. They will play well together. Be prepared to file rough spots on the couplers and use some graphite powder (never oil or silicone) to ensure smooth centering and coupling.

Weight is the last important factor in reliable operation. For HO, rolling stock should weigh one ounce plus one-half ounce per inch of length. For a standard scale 40' box car, which is about six inches long, that means four ounces (1 oz. plus 6 x .5 oz.).

Welcome to model railroading and this board. Good luck with your layout and be sure to keep us informed about your progress.
                                                                                                                                                                                            -- D

[Woody Elmore]

There is an old trick that works well - one truck on a car should be a bit looser than the other. That seems to help with derailments. Metal wheels will also help a lot.

[Doneldon]

NewCon-

Woody is right! Many modelers tighten one truck screw to the point that
the truck only swivels but leave the other truck screw loose enough that
the truck can rock a little.
                                          -- D

[NewConductor]

well, this is an older model train, back from the 70s i think, it's not even listed on Bachmann's site anymore. lol
I have tried tightening up the trucks but the screws only go in so far and there is a lot of tilt on both trucks on any given car. Should i put in washers? and which truck should be the looser one, forward or aft?

[jward]

it shouldn't matter which truck is tight. just remember not to over tighten them. both trucks must be able to swivel freely, any binding will cause derailments. the idea is to allow just enough rock in the one truck to allow it to negotiate the track, but have it tight enough to prevent the car from rocking. i never add washers between the screw and the truck, only between the truck and bolster.

[Doneldon]

Should i put in washers?

NewCon-

No. Adding washers will raise the height of your car which will change the height of your couplers, introducing another operational problem.

                                                                                                                                                                                                   -- D

[Rangerover1944]

Um, some of these old rolling stock have push pin trucks you won't be able to adjust them, by adding some weight to them it will improve performance a bit, some of these cheaper toy frieght cars are really light. It is possible though to convert them or "fix" them as your post indicates the screws won't tighten (plastic holes are stripped) by removing the trucks and gluing in a piece of "sprue" from old building or modeling kits. The "sprue" is what all the parts are attached to in kits. File it flat after the glue dries and flush with the bolster, drill and tap for a 4/40 hole #43 drill bit, purchase 1/2" 4/40 screws and attach your screws or you can use a sheet metal self taping #4 screw without tapping but you will need the #43 drill bit and a pin vise. Now they're adjustable. Jim

Most problems are poor track laying techniques, switch's/turnouts that have been tossed about or twisted from being put together and taken down a lot.

Are you running your train on carpet or do you have a permanent layout with the track attached to plywood or other kind of framework? Laying track and alining turnouts/switch's is the most important key to trouble free operation, BE A PERFECTIONIST when laying track, then work on the other problems with fine tuning coupler height, trip pin height (nobody seems to mention that too much and it is a major cause for deraiment), truck/wheel adjustments and adding weight. There are so many varibles that cause poor train performance, but can be fixed. Jim

[electrical whiz kid]

NewCon-

Woody is right! Many modelers tighten one truck screw to the point that
the truck only swivels but leave the other truck screw loose enough that
the truck can rock a little.
                                          -- D

[Heartily seconded!
Rich)