Kato #4 Turnout Problem

[Mutro]

My powered locomotives are derailing at my new #4 turnout.  It's just the powered locomotives that are getting derailed while the passenger cars go through okay. All my locomotives and passenger cars have no issues at #6's. The #4 derailments are inconsistent, occuring in different directions. Anyone know the source of this problem, and more importantly how to fix it?  Thanks for any help!

[Kamome]

Kato #4s are notorious so could be the common problem, but not necessarily.

 

It may be the throw of the point. I had the same issue with shinkansen if I used #4s on an elevated station mouth. The 4s would sometimes be problematic as the switch blade would not always butt up against the stock rail effectively when thrown. The problem sometimes happens more frequently if there is a slight raise in the track, like where the point switch wire is located in your photo. 

 

To rectify the common issue, you need to mark on the stock rail where the switch rail connects to it. Then carefully push the stock rail out enough to allow you to file out a small recess on the inside edge of the stock rail. This then allows the switch rail to switch into this recess giving a smoother transition.

 

Check out Mike Fifer's video from a good few years ago.

 

 

Edited March 4 by Kamome

[brill27mcb]

Try to see if the derailments happen at the leading edge of the moving points, or at the frog, or somewhere else.

 

It's also a good thing to check the gauge of the wheelsets. Sometimes they can be a little wide or narrow, causing problems.

Rich K.

[Mutro]

Thanks for the suggestions!  Ok, I watched the video several times and in slo mo.  I was able to perform the delicate procedure on the stock (straight) section. Unlike the video, the issue remained on the curved side as well, so a second procedure had to be performed.  Being that this rail is curved, pulling out and pushing back in was a bit more difficult.  But with these two procedures done, the #4 is operational, mostly.  Not perfect, as occasionally it still causes derailment on some of my trains (e.g. the mid-car powered 10-1527 485), but if trains come in ever so   s  l  o  w  l  y,  they seem to run though okay.  I hate to have these #4's in my layout, but in order to have the proper track distances, e.g. at platforms and barns, these are unfortunately unavoidable on my layout.

 

Since this seems to be a known and recurring issue with the #4's, I wonder why KATO hasn't fixed them in their redesign/production?

[brill27mcb]

The inability of adhering to the Kato standard 33mm spacing between parallel tracks when using the "#6" track switch (points / turnouts) and Kato 15-degree crossings is a long-standing critical flaw in Kato's track geometry. My understanding, from Charlie Vlk (an accomplished professional modeler who once worked at Kato USA) and others, is that the so-called "#4" 481mm track switch was Kato's original standard design, and the so-called "#6" 718mm (neither design really conforms to prototype #4 and #6 designs) was added to satisfy demand from North American modelers who were used to, and wanted, more gentle diverging curves. If you look at these two pieces, the #4 is much more engineered (selectable power routing, adapter short straights, etc.) than the #6, which also has a more cheaply-made frog and other changes to reach a lower "price point." If I am remembering right, the double-crossover does use the "#6" frog, while the newer one-piece single crossovers use the #4 frog.

 

In the earlier Japan-only market, Tomix had its 541mm radius track switch, and Kato had its 481mm radius track switch. These were pretty comparable, and in fact in comparing these two, it was Kato that could claim having the wider radius.

 

Some of the aspersions cast on the Kato #4 by John Sing and now by N-Trak / N-Rail have to do with trying to run U.S. model trains built to NMRA flange, wheel and track specifications on track that was designed in and sold in the Japanese market, where NMRA specs (or Europe's NEM specs) were irrelevant. The problem is compounded by the use of the metric system in the track designs versus designing in inches in the U.S. - little inaccuracies crop up. In your situation, you are running Japanese trains on Japanese track, so that's not part of your issue.

 

While filing a notch in the stock rails does help reduce derailments, it is not prototypical and does not look prototypical.

 

Rich K.

[cteno4]

Rich,

 

I heard the same info from Charlie and others in the past on Kato points.

 

unfortunately even Japanese trains can be touchy on #4 points. It’s kind of random in our club’s experience, tuning helped but still more issues than #6. Not many but for show running was just a bit more pain when derailments happened, so we eventually moved to #6 for club stuff. I’ve spoken to some folks that seem to have no issues with #4 points, so go figure.

 

cheers

 

jeff

[Mutro]

I like their products but the #4 doesn't speak well for their tag line "KATO Precision Railroad Models"

 

[Wolf]

I had issues with 2 out of 6 so far, and decided as well that these 6 were the last I use.

 

At the shop I think the layout runs five #4s, and none had an issue. Its hit and miss really, no clue what they do there (and admit by now I stopped investigating and just work around it)

[bill937ca]

9 hours ago, Mutro said:

I like their products but the #4 doesn't speak well for their tag line "KATO Precision Railroad Models"

 

I think it is not an issue engineering but of the politics of appealing the the NMRA standards crowd while appealing to the traditional Japanese home base.

[cteno4]

Well it is an engineering issue as we have had plenty of issues with just Japanese equipment running. It’s frustrating as it’s a very random problem and never really been addressed.

 

jeff

[Mutro]

Just installed two more #4's and experienced same derailments. Filing away at the critical parts of the rails (both on the straight as well as the curved rails) per the Mike Fifer's video (see above Youtube link) solves the problem.

[cteno4]

Great to hear Mutro!

 

jeff