simple, cheap, effective. How to make foam springs to improve contact between truck conductive towers and the long frame contact strips on each side of many Kato locomotive frames.
I've never had a problem with Kato locomotives with this design. This seems to be a cure for which there is no known disease.
Hmmmm....I've never had this problem before with Katos. I have a few of their locos of this design and never a problem. I wonder if it's the way he installed the sound decoder.
I've only had an issue on one used loco I purchased, where the strip and been bent all to hell (an E8). Replaced with new strip, all good
I have a funky E8 as well. No manner of tweaking the strips helped. Tried some foam (just for grins), and it worked. I'm thinking, in my case, that the plastic saddle was out of spec (I got the engine used...).
unlike many earlier posters, I have had contact problems with older similar but not identical locomotives, e9's and PA's. I hard wired the contact legs from the trucks to the decoders, using short pieces of wire from the excess on decoders. If required for maintenance, it's eas to unsolder and resolder, but I sure would have done this as although the video is long and tedious, the process should be simple and easy.
The most reliable way I found was to solder the motor leads directly to the decoder or the lightboard that came with it. I have ditched all the little grey plugs. Never had an issue since. I am not a sound decoder guy, to many locomotives for that. But the Digitrax and TCS decoders, once properly soldered, never have any issues in any of my E-8's, PA's, PB's, P42's, F3's and F7's from Kato
Those that use small sample sizes based on memory to discredit an effort to help others with a problem I had, wow just wow, thought railroaders were more logical rational and resonable than that. it is a problem, on some locomotives. gh, big break from you guys this weekend. not the response I expected to be called a liar because I dared point out an actual problem with a Kato locomotive.
Ken, No one is calling you a liar. And, many of us responding are not “small sample sizes.” We are just highlighting that this is not a common occurrence (but I also noted that I have seen the problem, though easily fixed). In my early days, I had a similar problem and tried a variation of your foam method. Once my experience grew to understand what to look for, I now know how to repair/avoid the issue.
I was certainly not calling you a liar, as I mentioned I had the same problem with a slightly more difficult resolution.
sorry my bad, and my apologise. took the comments wrong. I never thought it was common as I have 5 Kato locomotives and only one had the problem, did the mod on both p42 as I had the other open but it did not show any space between the contacts like the one that was an issue did. edit: Probably still good for me to take a break, be right back when I chill out
Sounds like a reasonable solution to a problem that doesn't involve soldering that has to be undone ever time someones has to do a major servicing.
I have so far had no problems with Kato loco's but one never knows in the future plus it might help with other bands. Soldering I'm not as good as others so this may help. Thanks Rick
I was not disputing your post, just sharing that I have never had those issues with any of the multitude of locomotive I have. I found that soldering the contacts to the decoders actually put a bit of spring in the contact strips to make very good contact. In addition, I will tell you the the speaker magnet has no effect on the decoder. This is twofold, first the strength of the magnet is relatively small. Second, the speaker magnet is a ring configuration and 90% of the magnetic field is inside the ring and the other 10% are held pretty close to the outside of the magnet. So there is nothing to be concerned about here.
I've seen these Katos show issues with contact and conductivity. Most folks thing "MORE PRESSURE!" but they're simply trying to grind those contacts through a layer of oil or oxidation. Cleaning the contact posts & the brass strips, and applying a minuscule amount of oxidation inhibitor will cure most locomotives that seem to have "bad contact" from truck posts to frame spring strips. Same goes for Bachmann tenders; those things are over-oiled and made with real cheap metals, oxidation takes Bachmanns off the line maybe as often as split gears! Kato had done a lot of research to get these locos where they will track well with good spring rate; those brass contact strips are essentially their leaf springs, were it a car suspension. So, modifying the static level of those contact strips seems like a good idea until you realize it changes (a small amount, but nevertheless) the tracking, curve approach, and ride height of these engines on anything but a workbench. This is reminiscent of he Athearn F59's... they had a horrible design with a short spring contact strip providing balance to the loco, the truck being free to let the loco rock. The huge flywheels caused them to shudder when the contact strips wore, or were put in poorly at factory. Bending those strips was a desperation move. Isolating truck rock with a shim of styrene solved the problem a hundred fold more reliably. Kato spent a lot of time orchestrating the suspension geometry of this modern loco chassis design and many folks (not necessarily original poster above) who have the problems described here have either A) bent the strips during disassembly/reassembly B) installed aftermarket boards of different thickness than Kato's C) forgotten that those brass strips are nearly as susceptible to oxidation and filth as the rails we so fervently clean on a frequent basis Nothing against poster and his solution, but a little cleaning goes further than forcing parts together "tighter"... force is a last resort, in toys and in life! YMMV, & final thought; If you want better truck tower contact on a similar loco, I'd recommend filing a notch into the post about 3mm from top, and sliding a coupler spring down onto it that pokes about 1mm over the top. The spring's end will etch and contact well, without (due to its much milder force) making major changes to the primary contact strip's spring rate or static position.
It did not change tracking curve approach or ride height at all. the weight of the locomotive rides on the truck and the contact strip provides no spring loading of any kind. It does not affect the angle of the truck or anything about the truck. Literally there is no way for this thin metal to be used as a leaf spring to balance the locomotive it would provide zero effective resistance given its materia qualities and the locomotives weight. The Kato design is not using the contact strips as any kind of suspension. the weight of the locomotive overrides any minor resistance of the contact strip, which has zero leverage above the contact point and would need to be much stiffer to act as a leaf spring. The insinuation that this mod will upset tracking? seriously why go over dramatic negative about stuff? foam density is measured in durometer, you do not mention that you simple eschew all 'foam' and offer an invasive damaging method that uses a coupler spring, the tiniest little bit of fiddle to play ever. File the internal parts instead of use an appropriate soft material as a spring? I got an A in materials for product design in college, received awards online for machining miniature steam engine, and I can say with expert training and experience that foam can approximate the surface area pressure a spring can with this mechanism in a safer and less invasive way. Suggesting an invasive modification that damages the locomotive and uses a coupler spring which is tiny and easily damaged, versus using foam of thickness and durometer to achieve that same amount of pressure. I am boggled that was offered as a better solution, it is not in any way. seems like I will be attacked for the most simple attempt to offer some help, and now its gone to hurting those that might read this with a mess of accusations that I made up stuff and bad advice to confuse any readers. this sucks, I dont want to have to correct everyone that feels some bizzare emotional need to attack me about this minor mod. seriously what the heck? mods maybe just delete this whole thread. tried to help others but the trolls will not stand for it. I cant come in here and correct the BS every morning its already depressing and negative for 2 days now.
seriously, to those that rationally and sanely replied with 'hey thanks I have /do not have this issue but it may help someone' your awesome just for being normal. the rest seriously it wasnt that big a deal as you made it out to be, for your emotions, which is not fair or good for model railroading or this website. edit: ok so this is not going well, what do I need to do to make it less hassle? not post anything technical without a disclaimer of some sort? not sure why this mod is getting so much flack. the first negative post was 7 minutes after I posted this, the video is 19 min long and the poster didn't even watch my demo just proclaimed it was nonsense. this seems pretty unfair to me, but so many are taking exception to the post, what is the deal? how can this work better?
On straight and level track you may be correct (like I said, on a workbench)... but on any track that's not absolutely dead flat across rail heads AND across the length of the engine? The trucks will rock away to the left or right side of their static seat in the frame (where the gear tower is) and that brass contact moves to compensate and absorb the motion while maintaining contact. If the trucks didn't rock back/forth and side/side they would lose contact constantly (on realistic track flaws) from rigidity, and if the brass contacts didn't move to compensate for that rocking they would lose contact from the boards (on realistic track flaws), and that's just silly. Play with the trucks and watch the way the brass strips maintain their contact. That being said, I never said anything negative about your post; I just noted that your solution to poor contact in this loco wasn't going to help the vast amount of problematic Kato's. Nearly any Kato with factory parts & poor contact either has a misaligned (re)assembly or it's dirty. I fully hope you don't let this post get under your skin, dude. As said/implied many times by the responses, these are the best locos on the market as far as R&D and design, and you're finding here that people who have literally hundreds (I have seen his boxes!) of these Katos have not experienced the need to shim anything. I wish you the best of luck and look forward to watching more of your videos!
OK, just saw this posting, and I'm interested in this as a possible solution to my problem. And it is a real problem. Been running Kato diesels for years with only occasional minor contact problems that had all been solved by making sure that little gray plastic contact clip that keeps the decoder in place is properly seated and sometimes using kapon tape to ensure everything is in place. But an F7 I bought 2 1/2 years ago and fitted with a digitrax decoder stopped running a few months ago. It is a contact problem--actually that little gray plastic contact clip does not seat properly. The plastic clip is fine because I've replaced it with a new one. Anyway, I have not gotten around to fixing the problem by soldering the contact strips and am intrigued about using a bit of foam as suggested. So, when I get some time, I'll give this method a shot, and will let you all know how it works. Cheers, Rick
