5050 Posted January 5, 2014 Share Posted January 5, 2014 What are peoples' feelings about these? I must say that mine are rather ambivalent as I am experiencing problems with stock fitted with them. I have one point on my WM layout (Peco Setrack RH curved - a very important one that all trains have to use) that causes derailments in a facing direction to stock with Kadee trucks. Rigid 'standard' trucks generally traverse it OK. The leading truck wheels ride up over the tip of the blade on the outside even though I have ensured that it fits very snuggly against the stock rail. B2B etc. are all OK with my NMRA gauge. The point is very nearly at the bottom of a down grade and is the junction of the main line and the mine tippler branch and so logistically, it is a very key location during operation. I have tried to get a bit of cant into the track bed around the curve which is of necessity quite tight (average 18" probably). I get the feeling that the Kadee trucks allow axles to misalign themselves vertically. They certainly don't appear to offer any better running than rigid ones IMHO. Any suggestions as to what I could do to improve matters? Should the springs and 'sliders' be lubricated for example? Link to post Share on other sites More sharing options...
shortliner Posted January 5, 2014 Share Posted January 5, 2014 Paul - There are two completely different versions of the Peco Curved Setrack point - see photo - if you have the old one, which is both shorter and tighter, there may be no cure for modern stock - if you have the newer version, check the width of the tracks at the railhead - I had one that was slightly warped and tight to gauge where the blades met the stock rail - and it may not be the trucks that are causing the problem Link to post Share on other sites More sharing options...
5050 Posted January 5, 2014 Author Share Posted January 5, 2014 Hi Jack, it is one of the newer larger radius ones and, if anything, gauge is slightly wide especially at the toe. I also had problems with the little contacts under the tips of the blades. The blades curve away so sharply that they hardly touch the stock rail. Good job I have fitted a belt-and-braces under baseboard switching device. My stock is not modern - far from it! Mostly 40 footers (Athearn, Roundhouse etc.) and short hoppers with the odd 50 footer for slight variety. I have a pair of the earlier tight radius ones too. In stock for a very minimum space roundy-roundy perhaps? Link to post Share on other sites More sharing options...
shortliner Posted January 5, 2014 Share Posted January 5, 2014 Sorry not to be more help Link to post Share on other sites More sharing options...
RMweb Premium cnw6847 Posted January 5, 2014 RMweb Premium Share Posted January 5, 2014 I've not had any problems with kd trucks in general although they are not run over setrack points. I occasionally find the odd truck that derails may be screwed down a bit tight or is a bit loose and needs tightening. Link to post Share on other sites More sharing options...
5050 Posted January 5, 2014 Author Share Posted January 5, 2014 Sorry not to be more help That's quite all right old chap I used Setrack rather than Streamline in this situation because I needed the tight curvature. I have lined the checkrails with thin shim to help finer wheels avoid the nose of the crossing which helps a bit. Link to post Share on other sites More sharing options...
CVSNE Posted January 7, 2014 Share Posted January 7, 2014 One of the best moves Kadee made was getting rid of the stupid little springs (which didn't function, and certainly don't look like a prototype spring assembly) in favor of their new line of "solid" trucks. The new trucks have considerably less "slop" in the axles - a problem with the previous sprung, three-piece trucks. Link to post Share on other sites More sharing options...
5050 Posted January 7, 2014 Author Share Posted January 7, 2014 Well, I've lightly lubed the sliding parts and springs on 3 Kadee truck fitted cars, given them a good 'squeezing to make sure they loosened up - and they still come off. Rigid trucks work fine. The axles definitely don't appear to line up (looking from the end of the truck) even with this treatment. I reckon its a waste of time in this scale fitting centrally located coil springing especially on such a short wheelbase item. Looks like I'll be searching out a supply of bog standard rigid trucks as replacements. Link to post Share on other sites More sharing options...
Feather River Bill Posted January 7, 2014 Share Posted January 7, 2014 One of the best moves Kadee made was getting rid of the stupid little springs (which didn't function, and certainly don't look like a prototype spring assembly) in favor of their new line of "solid" trucks. The new trucks have considerably less "slop" in the axles - a problem with the previous sprung, three-piece trucks. I agree CVSNE...old Central Valley trucks were the same. My Dad had many old cars with them and the slop was very noticeable. Link to post Share on other sites More sharing options...
Adrian Wintle Posted January 7, 2014 Share Posted January 7, 2014 ...old Central Valley trucks were the same worse. Based on the ones I have, I have amended your comment... Adrian Link to post Share on other sites More sharing options...
Feather River Bill Posted January 7, 2014 Share Posted January 7, 2014 Based on the ones I have, I have amended your comment... Adrian Edit accepted! My Dad thought the world of them...still does. Maybe that's why he models Marklin now! Link to post Share on other sites More sharing options...
highpeak Posted January 8, 2014 Share Posted January 8, 2014 I thought the old CV trucks, at least the passenger ones, were well thought of? Some research I did suggests that there were two iterations of some of the trucks and the newer one was not an improvement.The Kadee design was poor, partly because the springs were ineffective, partly because the truck seemed to me to easily go out of tram, and partly because the springs looked terrible. Link to post Share on other sites More sharing options...
5050 Posted January 9, 2014 Author Share Posted January 9, 2014 Looks like I'll be searching out a supply of bog standard rigid trucks as replacements. Any ideas as to where I could source some? Nothing to fancy, standard old Athearn would do for me. Link to post Share on other sites More sharing options...
The Bigbee Line Posted January 9, 2014 Share Posted January 9, 2014 Any ideas as to where I could source some? Nothing to fancy, standard old Athearn would do for me. Try Accurail http://www.accurail.com/accurail/parts.htm $15.98 for 12 sets Link to post Share on other sites More sharing options...
5050 Posted January 9, 2014 Author Share Posted January 9, 2014 Try Accurail http://www.accurail.com/accurail/parts.htm $15.98 for 12 sets Thanks for that. Does anyone in the UK sell them ex-stock? Link to post Share on other sites More sharing options...
The Bigbee Line Posted January 9, 2014 Share Posted January 9, 2014 I usually make an order direct with Accurail. Their other parts and decals are useful. Link to post Share on other sites More sharing options...
Andy Reichert Posted February 24, 2014 Share Posted February 24, 2014 I'm going to open can of worms here and say that this issue has a long and complicated multiple set of in-depth answers. Unfortunately, those may not be easy to see unless you are prepared to get more into understanding the way wheels ride on rails, than you usually need to just to run out of the box trains. There is a huge “suspension” article on the "CLAG" P4 website, but I'll try and simplify things a bit here.#1 First thing to know is that Kadee trucks aren't really "sprung". They are mostly "equalized” and only a little bit “sprung”. See all below for what that means.#2 Equalization in layman’s terms can more easily be understood by imagining the problem of eating out at a nice restaurant, that has four legged tables but an uneven floor in some places. So only three legs of the table are actually resting on the ground, and one is slightly up in the air. Every time you forget and rest your arms on a table on an uneven part of the floor, it rocks across the diagonally opposite firm legs and throws your date’s water glass into her lap. Sure they can (and usually do) put a wedge under the fourth leg, but then you can’t move that table somewhere else.The simple cure for a restaurant that moves its tables around, is to have 3 legged tables - they are always stable on any shape surface. But we don’t have 3 wheeled railroad trucks, so for US trains running on not always very flat and smooth US tracks, they use equalized trucks instead. #3 Equalization for a four wheel truck, usually means that each of the two side frames of the truck are made to pivot independently, in their centers, at the bolster ends. So one sideframe can tip to match the changing height of a bumpy rail on one side, while the other sideframe can stay level on it’s level rail - and vice versa, and all such up and down combinations. But because the weight of the car is sitting on the bolster, the weight on that side of the bolster rests on the center of the pivoting sideframe and is always split evenly between that sideframe’s two wheels.In Kadee’s case, their double or triple springs design brilliantly forms a free turning pivot and bolster to sideframe, weight support. As one wheel rises up to ride over a bump, its side frame tilts up over that wheel. That means its closer spring in that sideframe compresses slightly, while the farther spring stretches out to match, and the force on one spring is almost completely cancelled by the opposite direction force on the other spring. So no net force fighting the side frame tilt. And not only does that look prototypical, it’s pretty much the same way the prototype trucks work.If the model car is extremely heavy, or all the wheels hit a large bump together, then the springs do actually all compress slightly, but that’s the exception rather than the rule. Although quite thin, the springs are really too strong to give a soft car ride over just normally uneven track.#4 All the above means that Kadees are in fact some of the best trucks that you can get for proper track holding and smooth running. Why? Because the wheels will automatically (and freely) raise and lower over track bumps without changing the weight that sits on each wheel. Additionally, they will not transmit as much of those bumps to the car body. So they will stay on the rails, even on ridiculously uneven correct gauged track, if properly mounted to the car. But for the same reasons, they will find places in your track where a bump or bad point or rail joint edge is serious enough to lead a freer to rise wheel over the rail edge. The answer in that case, is to fix the track.All rigid tracks OTOH, act like the restaurant’s 4 legged tables. If the track isn’t level, or bumpy, at every instant, one wheel is always going to be slightly airborne, and not resting firmly on its rail. So rigid trucks inherently rock over uneven track and whichever wheel is lightly loaded or airborne at each instant, is much more likely to derail.#5 But there is still one extra aspect to consider. Any layout that has any uneven track, or grades and curves mixed together, will have situations where to all intents and purposes, the track is geometrically slightly “twisted”. That means that any truck, whether rigid or equalized, will need to tip sideways, to the left or right, in order to be sitting firmly down on any track section that is tilted the same way.For track that is twisted, i.e. tilted in different directions in two close together places, then all two truck cars also need to be able to sit firmly with each truck tilted at different angles to match the track. If the trucks are firmly mounted to the car body, then the whole car will rock and be prone to derailment. Simply equalizing just the trucks can’t solve that particular needed movement.#6 This extra tilted track problem is rather like considering the whole car as a four legged table. On of the very simplest way of fixing it, is to make the whole car effectively “3 legged”. We make sure the bolster pivot screw is firm on one truck and loosen it off a little on the other. Now the whole car body follows the tilt angle of the track under the firm truck, like two legs of a 3 legged table, while the loose truck is free to tilt to match the different tilt of the track under it. The loose truck pivot is acting as the “third leg” of the car body, which can sit down on the firmly on the centre of the bolster, regardless of the angle of the track under it.I have to add, this simplest fix is not much liked by the Scalefour Society technical types, as it isn’t mechanically symmetrical for handling any strong coupler forces, nor as smoothing as springing the whole car instead. It does however make a huge improvement in stability for the average HO RTR US box car. And installing working soft springing instead for HO US boxcars is a whole major area of complexity and difficulty, that not many modellers can fully handle.#7 As I expected, this has already become a long post. And it’s barely started on answering the original question. So I would say the trucks are unlikely to be the real cause of the problem. The down grade into the sharply curved turnout, and possible faults within the turnout itself are far more like to be the cause of the derailments, despite the rigid trucks appearing to work better currently. And maybe the car weights are having an effect. I switched over entirely to using equalized trucks, long ago, and never get any derailments caused by the cars themselves, at all. But I do have a few cars fitted with rigid trucks that I use for finding track problems. And there arlots of ways of making those.Andy Link to post Share on other sites More sharing options...
Adrian Wintle Posted February 24, 2014 Share Posted February 24, 2014 And installing working soft springing instead for HO US boxcars is a whole major area of complexity and difficulty, that not many modellers can fully handle. Besides which, if you sprung it properly you wouldn't get the rough track wobble so liked in Youtube videos... Link to post Share on other sites More sharing options...
Andy Reichert Posted February 24, 2014 Share Posted February 24, 2014 Besides which, if you sprung it properly you wouldn't get the rough track wobble so liked in Youtube videos... Which you tube videos? Prototype or models? Andy Link to post Share on other sites More sharing options...
Adrian Wintle Posted February 24, 2014 Share Posted February 24, 2014 Which you tube videos? Prototype or models? Andy The prototype videos that show shortline trains on under-maintained tracks with the cars rocking and rolling. Link to post Share on other sites More sharing options...
The Bigbee Line Posted February 24, 2014 Share Posted February 24, 2014 I have fitted Kadee sprung trucks as the norm. I know they don't like Peco 2' radius turnouts, but 3' are OK. Derailing on the interface between the switch and the closure rail. Likewise I fit 'side bearers' to stop cars rocking. That's my 2 cents Link to post Share on other sites More sharing options...
RMweb Premium New Haven Neil Posted February 24, 2014 RMweb Premium Share Posted February 24, 2014 I also have isues with Kadee trucks derailing, but I freely admit my Peco code 75 and 100 track isn't the best. Garage layouts suffer a lot with humidity changes. The one turnout about to be binned though, is a large radius curved, which derails anything propelled over it and I can't see why! I have a lot of spare rigid trucks if the OP wants them, no idea what types they are though, I struggle to tell the difference with a lot of them. Link to post Share on other sites More sharing options...
5050 Posted February 24, 2014 Author Share Posted February 24, 2014 Well, as a very long term member of the Scalefour Society (and having built several successful P4 exhibition layouts over the past 35-40 years) I know all about 3-point suspension and equalisation and pivoting trucks differently at either end. The simple point of my problem is that Kadee trucked vehicles came off the track on one point and rigid trucked ones didn't. I have removed the Kadee trucks from the offending vehicles, fitted rigid ones (probably old Athearn ones) in their place and now they all run perfectly. Problem solved! I went into US modelling to get away from the strictures of P4 and I can truthfully say that I am 99.9% satisfied with the result. However, I still continue to extol the virtues of P4 for UK 4mm modelling and have several 'projects' that I would like to build once the US bug has passed. If it ever does................................ Link to post Share on other sites More sharing options...
Andy Reichert Posted February 26, 2014 Share Posted February 26, 2014 Just so long as everybody realizes that swapping the trucks is fixing the localized track problem symptoms. And not a Kadee truck design problem. Kadees work far too well to be given a bad reputation for the wrong reasons. And the common understanding here is that the older versions of Peco track do not comply at all well with the US NMRA standards. I've also been a long term Scalefour member, and I must say, learned an awful lot of good things from the Society. Although in my time there, I didn't find anyone who seemed to have known beforehand that having curves leading on and off grades produces track twists. Possibly because P4 layouts tend to be mostly flat and short, they don't ever come across the problem. And I don't think there are any working P4 model Roller Coasters to teach them either . . . . BTW, If you ever decide to model on a grand scale in the in the US fashion, then helixes, which have those and other problems in spades, are almost de rigeur if you want your layout to be written up in a US model magazine. . BTW. I do like your "handle". It's familiar meaning for me, is the 5050 class of "Hollywood Cars". Probably the best known of all the Los Angeles Streetcars, partly because they ran past Graumans Chinese Theatre, and partly becuase they appeared in so many 30's and 40's Hollywood films. And of course, eventually "starred" in "Roger Rabbit"! Luckily I was able to collect a few of the very rare models, so I get to still enjoy them long after the originals have gone. Andy Link to post Share on other sites More sharing options...
Adrian Wintle Posted February 26, 2014 Share Posted February 26, 2014 BTW. I do like your "handle". It's familiar meaning for me, is the 5050 class of "Hollywood Cars". For me it brings to mind CNW 5050, the first of their GP50s (only because I have a model of it). Adrian Link to post Share on other sites More sharing options...
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