Turnout question

[rrinker]

 Keep blaming the Atlas turnouts, but check the wheel gauge on the loco. Every single car or loco that ever 'bumped' through my Atlas turnouts, both #4 and #6, were proven to have out of gauge wheels when checked with the NMRA gauge. Once fixed, there was no more bumping. Even larger locos like a Broadway GG1, PCM T-1 Northern, and Broadway M1 Mountain could run through all the turnouts at warp speed without derailing. That's my 'torture test' - everything must pass over the track at greater than realistic speeds reliably at which point I am satisfied that the trackwork is solid. The onlt thing I've ever done to an Atlas turnout is occasionally file the edged of the point rails. I've NEVER gone to the extremes of filling in the frog flangeways and cutting new flangeways. It simply isn't necessary.

                                 --Randy

[Papa G]

It's nice to have so many willing to share their experience and knowledge. Thanks for all the great feed back.

[Allegheny2-6-6-6]

 As a general rule of thumb Steam engines do not run well across anything under a #6 turnout, a small 0-8-0 or 0-6-0 no problem with the exception of non powered frogs So that big 4-8-2 is not going to like that small of a turnout.

[JoeinPA]

 To add to what Ken said, Atlas #4 turnouts have rather sloppy frogs that cause wheel drop.  This cause the loco to lurch or wobble as the wheels go through the frog.  The #6 turnouts seem to be better constructed and are not as much of a problem.

Joe

[cudaken]

  First to the site. What wheels are derailing first, pilot wheels or drivers?  As stated, check the wheels gauge first.

  All so, how do your other engines handle the turnout? Do other steamers handle the turnout OK?

 On some of my BLI steamers the Pilot trucks would pick the diverging route. I added some weight to the truck and it fixed the problem. 

 Far as the wobble, try sanding down the frog. Atlas frogs are normally to tall.

          Cuda Ken

[IRONROOSTER]

 MTH claims it will operate on 18" radius curve and the Atlas #4 is actually a # 4 1/2.  So it should work.  Get an NMRA gauge and check your turnout especially the flangeways and your locomotive wheels. Check your engine for possible binding.  If you have another Atlas #4 turnout, try it there.

Good luck

Paul

[selector]

If it is a curved diverging route, such as on the regular Peco British style turnouts, you would definitely want at least a #6.  But even a high-diverging-angle N. American true #4 made commercially will give you problems, and it may be the frog and the guard rails.  Quite often the spacing between the guards and the frog or the stock rails is so wide that they essentially do no guarding or guiding.  The result is staggering through the turnout on larger fixed frame steamers.

Have you gauged all the axles on the MTH?  It is a good thing to check that, and also the gauge at various points around the frog, as suggested earlier.

Sometimes the problem is a bent or twisted turnout, one that actually has a slight hump near the frog or a dip.  Even worse, the dip or hump is very close to the extreme ends of the turnout, well away from the frog, and the change in elevation will cause the frame to wobble.  Frame wobbles = train wobbles.

-Crandell

[wjstix]

IIRC a standard No.4 turnout is equivalent to a 15"R curve in HO at it's sharpest point. Many large engines won't go thru that sharp a curve. I suspect it would go thru a Walthers no.5 which about like a 26"R curve.

[gmcrail]

Papa G

My MTH Mohawk jumps and wobbles at any speed through an Atlas #4 turnout. Can someone tell me if I am using the wrong # turnout? Thanks.

 

A Mohawk is a lot of engine for a #4 turnout.  And Atlas #4's are notoriously sloppy in their track gauge and check gauges.  An NMRA standards gauge is the ticket here, I think.  Best to use another brand - Peco, Shinohara/Walthers, etc., and a longer turnout - at least #6.

[Papa G]

My MTH Mohawk jumps and wobbles at any speed through an Atlas #4 turnout. Can someone tell me if I am using the wrong # turnout? Thanks.