While looking for a solution I found a locked thread that explained my exact problem, that being my Kato NW2 has a wheel that will fall in the frog when the turnout is in the normal position which will stop the loco from moving forward. I will have to try to fill the frog with either silicon caulk or a piece of styrene as described in the previous thread. I have Peco C55 for about 10 years and have never had this problem with any of my other diesel locos. Here is my theory as to why the wheels fall into the frog. It seems the body allows the trucks to move quite a bit in the vertical direction as compared to other locos I have owned. I believe this is caused by the way the two halves of the body are loosely held together by the fuel tank. Atlas and most other manufacturers join the 2 halves using screws and nuts, which seems to work quite well at keeping the trucks in place. Not only does it look goofy every time the wheel dips into the frog and the whole loco looks like it hit a pothole but when the whole train comes to a complete stop it is quite another.
First of all, silicon caulk should be avoided. What you have is a gauge problem in either the switch, the wheelset or both. First of all, are you sure the switch is Peco code 55 and not Peco code 80? There is a difference in the flangeway distance at the frog. The C80 is NEMA (European) standard while the C55 is NMRA standard. Use a NMRA track gauge to measure both the flangeway at the frog as well as the wheelset gauge. You may have an out of gauge wheelset. It happens. If you don't have an NMRA gauge then get one. From what you state in your post above this appears to be a wheelset problem.
+1. They give off an acidic, corrosive vapor that corrode electrical contacts. You can tell by it's vinegar like smell. If you must use caulk, get the water based variety.
I checked the gauge of the wheels and the track and they were both within the NMRA standards which I checked with my NMRA gauge. I am thinking about drilling 1 hole at both ends and putting a screw and nut along with a spacer. This would clamp the 2 body halves together in order to capture the trucks properly. Or else just put the loco on the shelf..........
If you are going to try to solve the problem, shimming the frog is the way to go. It's not the track gauge. It's the wide flangeways and deep frogs of Peco turnouts that is not in NMRA standard. I watch my low profile wheel equipped cars wobble, bounce, etc, when running over the Peco turnouts on our club railroad all the time. But if you do shim the frog, if you have any engines and/or rolling stock with the "pizza cutter" flanges, they will then ride up on those shims most likely. So solving one issue very well could cause another. I know on other forums folks using fine scale wheel sets have shimmed their Peco turnouts due to the same issue. You may wish to do a little research on how they did this.
First of all let's determine which line of Peco the OP has. See my initial post on this above. So some questions need to be answered. 1. Does the switch in question have a plastic or a metal frog? If plastic then you have a code 80 switch made to NEMA standards (European) and you therefore need to shim the guardrails on both sides of the frog with a piece of .01 styrene. Shim the guardrail not the frog. Now if the answer to No. 1 is metal then you need to determine if the switch is C55 or C80 as Peco made switches in both rail sizes with metal frogs. If C80 you need to add the shim as above. The NMRA Gauge has a flange way gauge on it in case you can't determine if the switch is C80 or C55.
It is C55. I know this because I bought all my track at once as C55. I also have seen some C80 which works with C55 but the C80 only has one flange as compared to the C55 which has 2 flanges. I have metal frogs on my C55 Electrofrog turnouts.
i have the same problem with a set of 2 Kato NW2 engines i purchased at the last train show i attended , they also have low profile wheels . i have at least ten or maybe more SW switches , all can go over all my 40 plus turnouts , these Kato NW2 engines have small wheels and that is the problem . i also will be returning the Kato NW2 engines . i have never had a problem with any KATO engines but these are not up to KATO standards .
I had the very same issue with a pair of NW2's I had awhile back, even after I shimmed the guardrails on my PECO C80 turnouts. I've ran Atlas MP15DC's, S-2's, VO-1000's, LifeLike SW's and now Arnold SW-1's through my turnouts without issues. But NW2's wobbled and bobbled on every turnout, shimmed or un-shimmed.
Yeah, mine does it too using at least some of my Peco code 55 turnouts (haven't run it on my code 80 yet). However, I never really considered it a flaw or shortcoming of the loco itself. With the fine-tread wheels and all, I kind of always figured the loco was on a whole new level that the (current) track wasn't quite able to accommodate. I hadn't tried any frog shimming yet but figured I might try it at some point along with adjusting the wheel gauge. That said, the bobbing over frogs, while certainly not ideal, doesn't seem to bother me too much at the moment.
For those who are having the same problem try this. With the shell off and the fuel tank still installed, see if you can wobble the trucks up and down. Now take off the fuel tank and do the same motion with the trucks. Now pinch the two halves of the frame together and try to wobble the trucks up and down. When I did this procedure the truck motion was limited when the two halves were pinch together. I believe it is a poor design. Rather than rely on the fuel tank to keep the two halves and the whole engine together, they should have used the tried and true method that Atlas and other manufacturers have used, two screws and two shims, to keep the frame assembly together at the proper width.
