it may be all familiar to you guys, but (I am a newbie), maybe I am missing something obvious have my GP35, Jorger speed controller (what a beauty), few wagons and an oval to play - happy as a pig wallowing in **** but there is one thing that spoils the visual enjoyment: when crawling at low speed (and Jorger is great with my GP35) the last two wagons are lurching forward instead of rolling (I bet the guys in caboose have had their drink spilled by now) this is irrespective of which wagon I put as last and doesn't depend on how many more wagons are between loco and the last two wagons (ie it is just as bad with just two wagons behind the loco, as it is for the last two wagons of the consist of fifteen) the way I see it is as follows: with the train stationary the static friction has to be overcome, initially just the spring in a coupling gets compressed, until the pull is strong enough for the wagon to start rolling. Then with rolling friction being so much less than static, the wagon lurches forward until it comes against dead stops in a couplings, at which point wagon momentarily stops and the whole process starts again. So you have this unsightly jerkiness. Of course it is only the problem when you are pulling the train, pushing (at exactly the same low speed) is beautifully smooth - because there is no springs working in the couplings and the friction has now steadying influence. possible solutions: less friction on axles (steel in brass bearings?) metal instead of plastic wheels? different design of coupling? or maybe simply dry lubricant in wagon axles? .... would be grateful for your comments thanks Chris [ March 24, 2006, 11:23 AM: Message edited by: Chris Kaminski ]
there are little springs available (in coupler kits and sets) for just this problem. you pull one axle off a truck (on a caboose) and reinstall it with one of the springs on one of the wheel points. this causes the axle to drag providing enough drag to (hopefully) prevent the "slinky" effect. the spring in question is not the finest little coil that is used in the coupler pocket, but a "stringier" one -- with a few wide coils. slip over wheel point, slip truck onto that, slip the other wheel into the truck and you're set. hope this helps. dave f.
Would adding weight to the last car create enough additional drag to eliminate the slinky effect? I have also seen this with Marklin equipment though less than I see it with MTL or Pennzee. Rob
Rob, I have try putting a heavy car as the last car. It cut slinky down a bit. But the problem it still quite noticeable.
my tests also confirm that increasing the weight doesn't make any difference - it is the difference between static and rolling friction and the spring in the coupler that cause the bounce. Increasing or decreasing the weight doesn't solve anything because the both static and rolling friction are function of the same normal (gravity) force so the relationship between the two remains the same - just the absolute value for the two increases with increased weight. Chris [ March 24, 2006, 01:50 PM: Message edited by: Chris Kaminski ]
this possibly makes sense - increasing the friction on the axle has the effect similar to adding few more wagons behind the last one, in effect tensioning the set-up (same reason why wagons 1, 2, 3, 4 etc immediately behind loco do not experience the bouncing effect - because there are other wagons pulling on them at the end of the train) Chris
chris, do you have any of these springs? if not let me know and i'll send you some. after a while a person builds up quite a collection! let me know if i can help. dave f.
David, do you put one spring or two springs. I put two springs on my caboose, and it tended to derail. Maybe it derail because it's light. I will experiment again with the springs.
i do one per truck and only put a second spring on the second truck if it's needed. in N scale it seemed like one "sprung" wheel for every 6 or 7 cars kept the train moving smoothly. i don't know what it is for Z but i'm pulling 10 cars around my test track and not seeing any slinking. your results may vary. dave f. john, i've bashed and painted up a wide vision caboose i made out of two MTL shells. if i ever get the decals on (Rio Grande), i'll post a pic. thought you'd appreciate it. df
Thanks David. I will test my cars with one spring. I am also look forward to see your pictures of the caboose.
David, would it be possible for you to psot a picture of that springs? I want to see if I can make some myself. Thanks
Dave, I have sent you private e-mail (based on the info in your profile), but it looks like it hasn' reached you? It is awfully decent of you to offer. No I do not have any - I only just started and I didn't even know of their existence. Are they standard MTL part for this purpose? or is it your own solution from experience? I was going to check if they are available separately and try to get them from ZscaleMonster together with my next order (whenever it happens ...) I am based in UK so it would be very long way for a little spring on it's own thanks Chris
chris, hmmm!? i've gotten private messages before. i'll try you. the spring is a standard part for MicroTrains ... but it don't know the part number off hand. you can take a spring out of a coupler and stretch it out and cut it to about a penny's width. all you need is the drag on the axle. i can send you some, but if you have an order coming from zmonster, he can probably get it to you faster or easier. but i will send you some if you say the word (and i get your mailing address). i'll work on sending an email to you. dave f.
to whom it may concern, the springs in question are called "truck restraining springs". they are old Micro-trains part number MTL-1953. their new number (on the MTL website) is 001 12002 "N-2 truck restraining springs" 12 each for $1.55 these are the same springs used on N scale cars. same part, same part number, but you will also find them listed under Z accessories on a good listing of MTL parts. hope this helps. i'll try to get a picture if i can, but it won't be today. dave f.
