i have a brass tender that doesn't appear to provide a reliable conductive path between the track and locomotive.
This is after cleaning the wheels by running them across track covered with alchohol soaked paper towels, trying to clean the tender openings for the axles and cleaning with a bright boy the contact points on the tender and body.
I figure there are 12 movable points of contact:
obviously if either drawbar contact is bad there is no path
but between the tender and bodies and 4 wheels, there are redundant paths.
A wire soldered to the locomotive wire and screwed to the tender body may have helped, but there were still problems. It seemed pressing down on the tender may have helped.
are any of these contact points more prone to problems than the others?
greg - Philadelphia & Reading / Reading
Try connecting a #30 wire between the tender trucks and tender frame. That swivel point may need cleaning. Maybe contact enhancer between the tender truck and frame.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
There usually were only 2 options - either the tender only picked up from one side, in which case all the insulated wheels should be on the same side - though if a truck were turned the wrong way, it would be a dead short. Unless there are all sorts of wheel wipers, the other option is that one truck picks up from one side, and the other truck picks up from the opposite side. One truck will have a wire going to the loco, the other will be grounded to the tender chassis and transmit power via the drawbar.
Bypassing the friction contact tot he chassis with a piece of flexible wire may help. Also how is the tender's weight? If it's very light, it just may not press down on the rails hard enough to make reliable contact. Even on the wired side - the point of power transmission may be the needlepoint axle ends - if these are all gummed up with old dried lubricant, it will cause power pickup problems. If there are wheel wipers instead, the wipers may be dirty, or have become bent such that they are not making solid contact with the wheel they are supposed to pick up power from. This might only happen when the tender is standing on its wheels - if you pick it up and turn it over to look, everything may look to be firmly in contact. You might be able to put a piece of track on a piece of glass or plexiglas so you cna view up from the underside and see if the wipers make proper contact.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Adding wheel wipers that are hardwired to the chassis is a simple way of eliminating two mechanical contact points ....
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
I was going to say the tender only picks up current from one rail as one wheel on each axle is insulated.
Can you use a multimeter to do a continuity test and perhaps identify the poor connecting point?
Mark R. Adding wheel wipers that are hardwired to the chassis is a simple way of eliminating two mechanical contact points .... Mark.
Take a DMM set on Ohms and attach one lead to the non-insulated wheel. Take the other lead and work your way through the electrical path to the draw bar. Repeat as needed.
I would expect to see 1 ohm or less total. Use a flexable wire to bypass as necessary.
Jim
As I said in my original post, there are obviously two critical contact points on either end of the drawbar that I bypassed by a wire soldered on the locomitive and screwed to the tender.
this leaves multiple truck-tender and multple track-wheel-tender contact points.
it puzzles me that multiple redundant contact points can all fail at the same time.
it seems that minimizing the number of contact points, that Mark suggested, is the best approach
gregcit seems that minimizing the number of contact points, that Mark suggested, is the best approach
I was just going to say, Mark's pic is a good start. Better yet are wipers on BOTH side, everywhere possible. That's how I did decoder installs in my narrowgauge brass and it works well.
One big reason is that track conductivity can vary, not just from clean vs dirty track, but due to the slight variations in vertical alignment, etc. If you have pickup on just one side in both loco and tender, it doesn't spread the pickup area over the total wheelbase in contact like it would with wipers on both sides.
The more, the better when it comes to electrical pickup.
Mike Lehman
Urbana, IL
This is why I don't have brass locomotives.
Even with plastic, all wheel pickup on the tender is a help.
My first HO DCC Roundhouse steamers came with all wheel pickup on the tenders.
Bachmann DCC steamer tenders came with traditional pickup on one side of the front truck and other side of the rear truck. I modified the trucks for all wheel pickup with Kadee springs. Made a difference.
gregc i have a brass tender that doesn't appear to provide a reliable conductive path between the track and locomotive. This is after cleaning the wheels by running them across track covered with alchohol soaked paper towels, trying to clean the tender openings for the axles and cleaning with a bright boy the contact points on the tender and body. I figure there are 12 movable points of contact: the 4 wheels and track the 4 axles and tenders the 2 tenders and body the drawbar and the tender the drawbar and locomotive obviously if either drawbar contact is bad there is no path but between the tender and bodies and 4 wheels, there are redundant paths. A wire soldered to the locomotive wire and screwed to the tender body may have helped, but there were still problems. It seemed pressing down on the tender may have helped. are any of these contact points more prone to problems than the others?
It's hard to say without knowing how it's put together exactly. Do you use journal bearings as your transfer point from the wheels to the truck? The journals maybe worn out, or the axel points not designed for the truck. Or is it axel wipers?
You need to grab a volt meter with a continuity or Ohm reader and see if theres conductivity between the wheel tread and the contact point first.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
gregcit puzzles me that multiple redundant contact points can all fail at the same time.
Not long ago I installed a Loksound decoder into an Athearn Genesis F-7. It stuttered and bucked so bad I thought the decoder was faulty.
I replaced the decoder with an identical one and got the same results!
After Googling Genesis F-7 pickup problems I found that others had the same problem. How can EIGHT wheels in bronze strips not be able to conduct electricity?
After a thorough cleaning and degreasing it ran better—but not perfect—it wasn't until I consisted the engine with several others and ran it around the layout for about an hour that the problems finally went away.
I probably have about 2 dozen Genesis Fs and had this problem with two of them. Why? I could never figure that out.
A small application of CRC 2-26 helped immensely with contact problems, too.
gatrhumpyThis is why I don't have brass locomotives.
Some are better than others. They can be fussy but if there's a model you just can not get any other way it is worthwhile to make the modifications.
Good Luck, Ed
Had the same problem with the RTR RS-3 from AThearn. Even afte rreplacing the body bolster friction pickup path with wires - same problem. ANother unit worked fine out of the box, even with the friction path for one side pickup. SO yeah, while it seems like there are multiple redundant power paths, it can setill happen.
Read more about it here, Randy. I did the same thing by eliminating the push-on clip but after reading this bit from Tony's I think I'll invest in a few NWSL wheels.
http://tonystrains.com/athearn-genesis-pickup-problems-fixed/
I didn't plan to hijack the thread but sometimes any help with pickup problems may be worth looking into.
Ed
I was thinking about either filing away the plastic to make sure the bearings touch the metal, and/or using small flexible wire and soldering right to the square bronze bushings and avoiding the problem totally.
this webpage, http://www.55n3.org/cars/tender_wipers/, describes an approach for adding pickups. It also says to roughen up the surface and uses Neolube. I'm not sure if the surface was roughened just to help neolube stick or if it would be a good idea for any type of contact mechanism?
I don;t know about roghing up a contact surface - that's akin to the old sintered iron wheels in Athearn BB locos. Sure they gripped like glue, but electrical contact on them was always improved by switching to the NWSL turned nickel-silver wheels.
Now, if the wheels are blackened, I would definitely polish up the contact area. Pickups liek that on both tender trucks, with wires connecing inside to the loco, should be about as bulletproof as it gets. If the loco also picks up from both sides, that system should never stall, even on a #8 unpowered frog.
Edit: in the most recent DCC column in MRH, Bruce mentions that the nano-lube comes in some different weights, and he mentioned first applying the real thin stuff to 'soak in' to the metal and then apply a drop of the heavier stuff for longevity. Granted this was for gears, but the same sort of thing should apply ALthough how porous nickel silver wheels are to have a place to 'soak up' any oil is a rather curious question.
Keep in mind that Neo-Lube and Nano-Oil are commonly used on model RR stuff, but have different properties.
Neo-Lube is basically graphite in an evaporative suspension. The roughing-up helps give some better retention characteristics, as the graphite in the valleys helps feed it to the contact surface over time. It's also used to give a oily finish to rods and other stuff that is supposed to look like oiled steel. Do NOT get Neo-Lube anywhere you don't want electricity to follow, like on the insulation ring on drivers between the driver center and the metal "tire."
Nano-Oil (Nano-Lube is yet another item) is an oil or grease of various weights with micro-particles of some sort of slippery stuff (not graphite, but soem form of carbon) suspended in it. It doesn't evaporate, but continues to act as a carrier for the slippery stuff. I'm not sure about it's electrical properties, they don't say much about them: http://www.nano-oil.com/FAQ.html
I tried finding more product into on the Nano-Lube website, but they seem to treat that as secret stuff, but most of the product references point to its lube properties. Very well could have electrical contact enhancement, but you'll need to rely on the suggestions of other as to that from what I can see.
Rough surfaces increase wear and friction. You want a smooth surface as the contact surface is increased which leads to better conductivity.
If these snake oils actually did half of what they claimed we would be using them all over our vehicles.
Keep in mind that "rough" is relative in this context. What you want is something that is more visibly not smooth, not physically discernable by touch to be rough. Most of the time I see this trick used, it's simply taking some medium-fine sandpaper and swiping it lightly a few times across the bearing surface.
Only problem I see with this is that it becomes a never ending cycle - it works great as long as all those microscopic pores are filled in the the graphite material, but as it depeletes, more will have to be added to keep it running great.
Retained liquids or gels have always been something I wanted to avoid around electrical contact surfaces. The non-dry materials attract dust and dirt which ends up worsening any contact issue. Lessons leared from the time before learnign that one tiny drop of lubricate is plenty, and extra got on the pickups. Next thing you know, the loco doesn't run and there's a fuzzball on the pickup that you need to clean off. And unless all the oil or grease is wiped off, it just hapens again and again. Metal to metal is generally self polishing, until eventually the softer of the two materials wears out. Copper is not a good wiper maerial - anyone have HO slot cars in the 70's? How many pickup brushes did you replace, at least on the Tyco ones which I'm pretty sure were copper - the ones I had wore holes in them constantly. The Aurora cars I had uses a long shoe that spanned almost the entire underside of the car, none of those ever wore out.
i thought that when it comes to contact surfaces without any type of intermediary (i.e. lube), a polished surface, without any scratches (i.e. grooves) that can tarnish is desirable.
seems many modelers are even avoiding using bright boys to avoid scratching and leaving micro-grooves. I thought this is why gleaming is superior.
so i assume the web page suggests sanding (and therefore scratching) the surface to help hold the lubricant and is the axact opposite thing for a dry surface which you want polished to maximize the conduction area, minimize tarnish and minizing abrasion of the contact (i.e. wiper).
I think the issue with bolster contact on brass tenders is a bit of s special case. It's brass-on-brass, so they wear evenly, not dissimilar. It had to be wide enough to ensure good contact, which introduced some drag. Modelers being the way they were and are, give it a drop of lube. Or it flings off the wheel bearings, etc. If everything is polished, then you get a film between two relatively smooth surfaces. The intent of roughing it is to provide some points of contact that project through the film, overcoming the loss of contact caused by the film.
I'm not arguing one way or the other about this, just noting that people do it and it does seem to work here. I hardwire stuff, so not too big an issue for me. If you need to get a brass loco to run, at a minimum it might be useful if you're not intending to do more than test run it. YMMV. Disclamers appply. Just the facts, not trying to jangle anyone's chain.
rrinkerRetained liquids or gels have always been something I wanted to avoid around electrical contact surfaces.
Again, graphite is a bit of special case. Once the carrier evaporates, graphite is slippery without really sticking to anything. So it doesn't tend to suck up dust, grime, etc like oils do. I actually suspect that's why NeoLube was developed, because it's "special" stuff in another sense. The first of several uses listed is "nuclear applications..." I guess they'd have to kill you if they told you or something, but if something really needs to be vaporized, call Omaha...and make sure you use your NeoLube.
I've always used powered graphite on things like metal trucks with metal axles, for the very reason that it isn;t wet and won;t attract durt. It seems to stay put - but then the surfaces surely aren;t machined perfectly flat and would have micro cracks in them that hang on to the graphite particles. You can tell two carefully machine surfaces - if you put them in contact they tend to stick together as if they were magnetic.
I suppose in cases where the bearing surface wasn't readily accessible, having the graphite in a liquid carrier that evaporates could be useful.
mlehmanNeo-Lube and Nano-Oil are commonly used on model RR stuff
WARNING!
Nano Oil will destroy plastics. Please read this:
http://cs.trains.com/mrr/f/88/t/261415.aspx
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
hon30critter mlehman Neo-Lube and Nano-Oil are commonly used on model RR stuff WARNING! Nano Oil will destroy plastics. Please read this: http://cs.trains.com/mrr/f/88/t/261415.aspx Dave
mlehman Neo-Lube and Nano-Oil are commonly used on model RR stuff
Apologies on my off topic post but this has to be addressed;
with all due respect and years of experience with Nano oil, that persons story about his plastic drive train falling apart, in my opinion, is hogwash.
All the plastic gears on my Bachmann Shays ( after being retrofitted with the new plastic gears from Bachmann) glide along as smooth as ever, with no disintegration of anything. Thats 3 Bachmanns Shays, several 44 toners, 2-6-0, Roundhouse 2-8-0, Rivarossi Heisler engine rods, and many others.
These are at least 2 years with the nano products with no negative affects.
I would resist the urge to spread a message about a product without verifiable proof, as false claims do nothing for the consumer or company.
I call B.S.
"The true sign of intelligence is not knowledge but imagination."-Albert Einstein
http://gearedsteam.blogspot.com/
Well, I chose to respect my source, and as I said in another thread, I would be remiss not to report his experience with Nano Oil.
I am glad that you have not experienced any problems with Nano Oil, and I hope you don't in the future. However, the fact that you have not experienced problems doesn't prove that he hasn't.
Respectfully,