Switch BumP

[Bruce_Bennett]

Hello all,
Since Bachman doesn't make track (I hope) I think I can drop a name here. I'm using Atlas 83 track and switches. I've got a problem with SOME switches. I only have two locos at the moment. I'm just getting into this hobby. A 3 truck Shay and a 40 ton GE switcher.  Both these locos have a problem on the curve side of the switch. When comming up the bottom toward the split and going to the curve the front trucks want to slide off the outer track slightly until they get to a point in the curve. Then the inner wheel of the truck will bump or jump. Sometimes going where it's supposed to.  Other times not. This is rather hard to explain without a picture! Anyway, I was wondering if anyone has had this problem and been able to solve it?  Thanks for any help you might be able to give.

Bruce

[pdlethbridge]

I had a problem with my H16-44 like that the other day. It kept jumping on a crossing. I use code 83 atlas as well and found that a coupler was a touch low. When I fixed it the problem went away.

[jonathan]

Agreed.

I had the same problem.  The coupler trip pins (bent wire hanging down off the coupler) needed to be adjusted.  A kadee coupler guage will help you immensely.  Trip pins that are little too low, will catch on turnouts every time, always causing derailments.  Most of us have learned that the hard way.

BTW  Bachmann does sell track (EZ track).  Not to worry, you can mention other manufactureres.  Just keep it polite (per code of conduct).  The other company's aren't here to defend themselves.

Regards, and good luck.

Jonathan

[Bruce_Bennett]

I thank you for your advice but I have one question. How do I get the track gauge to run over the switch area? The one I've got (KayDee) only fits in between regular track.  Your idea does sound riteous though. I'll see if I can eyeball it!

Bruce

[pdlethbridge]

The trip pin should be about 1/32" above the rail

[OldTimer]

The track gauge does not run through the turnout. 

Set the gauge on a piece of straight track and set the loco on the same piece of track.  Push the gauge up to the loco.  The couplers should mate, be at the same height, and the trip pin on the engine coupler should clear the little shelf on the bottom of the gauge that Kadee calls the "foot plate."

If the trip pin hits the foot plate, the pin needs to be adjusted upward so it misses.  Kadee makes a special tool (item #237), or you can use a pair of needle nose pliers to gently adjust the trip pin. 

[Jim Banner]

If you would like to gauge the distance between the rails and the spacing through the flangeways, consider buying an NMRA track and wheel gauge.  It will also tell you if the spacing between the wheels is correct.

For those who are all thumbs on at least one hand, here are five rules of thumb for derailments around turnouts.  For those with only two thumbs, well, you can read them anyway.

(1) Do many of your locomotives and cars derail at the particular turnout or only one or two?  If only one or two, the problem is more like with those cars/locomotives than with the turnout itself.

(2) Are the rails in gauge?  How about the flangeways?  No use messing with the turnout if you don't know what, if anything, is wrong with it.

(3) Are the wheels that derail in gauge?  Check with a track and wheel gauge to find out and adjust accordingly if necessary.  Be sure to use the gauge parallel to the axle, not at an angle.

(4) Is the turnout and tracks connected directly to it flat?  They do not have to be level, but they do need to be in the same plane with no horizontal or vertical kinks.  A change in grade (slope) in or next to a turnout is virtually guaranteed to cause derailments.

(5) Are the moveable point rails closing tight against the stationary stock rails when the switch is thrown?  If not, the wheels on one side may try to go one way and the wheels on the other side to go the other way.

Just in case you have some spare thumbs on the other hand, here is another rule of thumb for turnouts:

(6) If the problem is with a steam locomotive, is the locomotive balanced?  The center of gravity and thus the point of balance should be above the center drive axle.  If there is an even number of drivers on each side, the center of gravity should be above a point midway between the center pair of driving axles.  All too often locomotives with smoke units are light in the front end and the front drivers rise enough to lift the pony truck off the rails.  If can look like a problem with the pony truck but is actually a balance problem.  Removing the smoke unit and stuffing the space full of lead often solves the problem.

If it is any consolation, the real railroads have to worry about these things too, except possibly item six.  If a real world locomotive were out of balance, I suspect they would first fire the designer and then pour concrete to add weight to one end or the other.

Please feel free to add to this list.

Jim   

[jward]

from what you describe it doesn't sound to me like the trip pins are the problem. if it were the trip pins, you'd notice the locomotive jump or hesitate when the pin caught. if you are using plastic couplers, you'd notice the coupler sagging after a few such snags.

is the point in the curve where the wheels climb the rail the polace where the moveable point rail pivots, and the solid rail leading to the frog begins? if so, try carefully filing the blunt end of the solid rail. from my experience with atlas switches, this is a problem area. if yourun your finger along this rail you will often feel the bump at the end of the point. this is most likely what derails your locomotive.....

[Bruce_Bennett]

God, I can't believe the amount of help you all have given me, thanks!  OK, It's not the pin. After looking very closely I can see that the first and second drive trucks on the Shay are NOT turning enough going into the turn. They jump the track and continue on straight. If I give the lead truck just the slightest help starting the turn, it seems to then finish the turn OK.  I flipped the loco over and looked for obvious signs of hanging up and couldn't find any. I put a little (very little) white grease on the drive axle spline and the screw holding the truck on. Didn't help! So, is this a problem with the switch or the truck?  I said in the first post my switcher has a little jump to it also making this turn, but it does make it. I'm open to suggestions.

Bruce

[jward]

you are saying that the shay starts to derail when it hits the switchpoints? file the ends of the points so that they are nice and sharp. your wheels are probably catching the end of the point and the flanges are riding the tops of the rail from that point until where they finally derail. if you illuminate the area with bright light and carefully watch what the wheels do you should see this happenning. if you put a bevel in the ends of the points it will help guide the wheel flanges where they are supposed to go.

[Bruce_Bennett]

I'll check that out and let you know, TO-MORR-OW
Good night!

Bruce

[Bruce_Bennett]

Hello all,

Well I stole my wife's makeup mirror and with my xenon flashlite got a very cloeup look at the inboard trucks as it goes into that switch.  The leading wheel is slicing the switch rail and following the inboard rail straight instead of following the switch piece to turn.   I've tried bending the leading edge of the switch piece slightly both in and out without sucess.  Any other suggestions?  I'm about to go get another switch and do the "switch switch!"

Bruce

[JerryB]

You definitely need to get an NMRA-type track & wheel gauge. It will allow you to determine whether the track / switch is the problem or if the wheels are out of gauge. They are available directly from the NMRA (you don't have to be a member) or for a higher price, from Micro-Mark.

NMRA H0 scale standards gauge ($12 for non-members):
https://www.nmrastores.com/Public_Store/product_info.php?products_id=53&osCsid=64mlpf1r7hipclej3mv22psq64

Micro-Mark H0 scale standards gauge ($18.50):
http://www.micromark.com/NMRA-GAGE-HO-SCALE,7530.html?sc=WGB&utm_source=GoogleBase&utm_medium=feed&utm_campaign=GoogleBase

For more information on getting your RR to work well including track & wheel tuneup, see the NMRA's beginners pages at:
http://www.nmra.org/beginner/

Look at this article on troubleshooting derailments:
http://www.nmra.org/beginner/derailments.html

Generally speaking, if only one piece of rolling stock derails, it is an out of gauge situation with the wheels on that piece of rolling stock. If several pieces of rolling stock derail at a single point, it is the fault of the switch or track work at that point. Application of a track & wheel gauge will save you a lot of time, as well as the frustration of changing something (like the turnout) without solving the problem.

One other thought: Have you checked to see that the turnout is level, along with the rest of the track on the approach and departure. Vertical 'kinks' can also produce derailments on various equipment.

If you determine it is the turnout, you probably need to file the points or bend them a little further to get good operation. Exchanging the turnout without really identifying the problem usually isn't very productive.

Hope this helps.

Happy RRing,

Jerry

[mabloodhound]

Bruce,
What you observed is called "picking the switch".   If you can't file/bend the switch point then a new switch may be in order.   But it is the point that needs fixing.

[pdlethbridge]

Are you using Atlas code 83 custom line or snap switches? I have had problems with the snap switches that don't close all the way, the custom lines do.