Steam tender wheel SLED cleaning

[mmagliaro]

We have had two discussions on cleaning and pickup recently, one on solving woes in the tender "sleds" of the Kato/Con-Cor 4-6-4, and one on just using electric mechanical "wheel spinning" cleaners. 

In the course of cleaning track and wheels on my layout, my two Walthers 0-8-0 switchers, I noted, had become annoyingly fussy and stall-prone, so I set about cleaning.   I cleaned the tender wheels with paint thinner, and that seemed to get rid of every trace of dirt or oxidation and leave them very clean.  They are pretty good wheels, with a high mirror shine to them.

But alas, the engines still ran lousy.  Other engines ran great over the same stretch of track.

I took one to the workbench, remove the wheelsets and the pickup "sleds" (very similar to the Con-Cor style),
and cleaned the sleds with 99% alcohol (and the wheels as well).  It ran better, but still not great.

Then I used some 1000-grit sandpaper and polished the surfaces of the sleds that ride on the wheelsets.
Success.  The engine ran magnificently. 
The same behavior repeated with the second engine, but I took photos as I did the cleaning and polishing, and made a surprising discovery.

The metal surfaces on the pickup plates, no matter how clean they appeared even with an optivisor, were pretty darn
awful until I polished them with the sandpaper. 
This makes me wonder how many 4-6-4 pickup woes are suffering from this.

I'm more concerned about the state of the pickup plates themselves.  Is the corrosion and pitting really being
caused by arcing?  A cheap phosphor bronze compound that oxides and "rusts" away?

[muktown128]

Thanks Max!

I would not have thought to look at the pick-ups.
The amount of corrosion is pretty bad.
Now that you have clean this off and sanded it,
I suspect this will corrode again and maybe even faster.

Is there something that you can coat these pick ups with
that will protect from corrosion?
Max-lube (a.k.a. Neolube)?

[garethashenden]

The mechanical connection between the wheels and the pickups or between two different pickups (diesel trucks for example) is just as important as the wheels when it come to cleaning. I know that everyone on here seems to disdain soldered wires, but they have their uses.

[victor miranda]

clean carefully

[up1950s]

Maybe a cartridge case media tumbler . Stick it in , leave it on for a few hours . should come out shiny .

http://www.cabelas.com/product/Lyman-PRO-Turbo-Tumbler/705522.uts?productVariantId=1376016&srccode=cii_17588969&cpncode=41-63182441-2&WT.tsrc=CSE&WT.mc_id=GoogleProductAds&WT.z_mc_id1=20015008&rid=20

[mmagliaro]

I don't think these will corrode any faster now that I've sanded them, because they never had any "plating" on them.
The issue is whether my 1000 grit sanding made them smoother than they were originally.  If it did, then they should wear less from now on, I would think.  And looking at the rest of that metal strip's edge, on the whole area that never touches anything, you can clearly see that it is not smooth.  So I would suspect that the whole edge was never smooth to begin with and that (hopefully) contributed to this pitting and wear.

A tumbler... hmmm even a rock tumbler or any sort of liquid polishing tumbler tool might do the job.
If you overdo it, you'll "polish" the thing until you change it's dimensions enough to cause it to stop working,
so Victor is definitely the voice of wisdom when he says "clean carefully".   Remember, this thing inserts
into the tender bottom.  The center "thumb" presses against a phosphor bronze strip in the tender floor,
and the curved arches ride on grooves on the backs of the wheels. So if you were to remove even .005" of this
thing anywhere, it would probably reduce its contact pressure enough to cause trouble.

BIG QUESTIONS:
Is this the reason the axle-point pickup scheme works so much more reliably?
When I look at these sled designs, it is hard to see why they don't work as well.  I mean, after all,
you have pressure strips pressing them down into smooth grooved surfaces on the backs fo the wheels,
and all the wheels can float independently and still all maintain contact, just the axle-point system. 
The contact surface is on the back of the wheel where it should not get dirty from the track.

And yet, these thing never quite work as well.  Is it because Kato's axle points are hardened steel, and they
continually polish the insides of the phosphor bronze cups to keep them smooth and clean?   Or because all the
force is concentrated just on the axle point, which helps to keep grinding the dirt and oxidation out of the way
(as opposed to the sled, where the contact is spread over a large area)?

What I wouldn't give to know what experiments and discussions Kato had when they worked
on the sled design and on the later axle-point scheme.

[up1950s]

The media used in the shell casing tumbler is not that abrasive to reduce brass . More like nut shells made actually from corn cobs and the size of large ballast .

[victor miranda]

Hi Max,

my answer is based on my obervations
and I have not been clever enough to think up a way to test
my thinking on 'why'

here goes.
Hudson tender is not a light weight.
it has 8 wheels doing pickup and the wheel base allows
for more certain pushing the wheels into uneven track
that is the leverage from one wheel to the thumb
allows better sharing of the sled.

the CC 2-10-2 and lifelike 0-8-0 are very similar..
just one wheel can lift the sled/truck and the other wheel gets no pressure
to set it onto the rail.

making sure the sled is loose in the truck helps a lot,
and the hudson truck still seems more reliable.

so there is a leverage and proportion and weight relation involved.
I know that if you put all the 2-10-2 tender weight on the sleds the wheels will not roll
and the hudson takes a lot more weight to stop rolling.

k axle points vs sleds.
the closer to get to the center of an axle/wheel the more pressure
is required to get a braking effect.
that by itself means that a tiny journal bearing is not an effective brake.
an axle point is an easy way to make a tiny and effective journal bearing.
Compare that to the sleds riding on a brake drum.

I can state that axle point pick-ups are not any more effective
than any other kind of pick-up unless the axle points-cups have the flexibility
to keep weight on the axle point. 

the axle points have to to the same flexing the sleds do.
the improvements from there are well worth  the efforts involved.
all the weight available can be used to maintain contact
and the rolling resistance from that contact will not stall the wheelset.

sleds work and they can only use a portion of the weight as electrical contact.

the problem with moving the sleds to the outside is controlling them.
they can ride on the axle and therefore be closer to center of the axle
and they will rub the wheel face unless one is very careful.
you can read that as not reliable in manufacturing.

the cones allow the wheelset to shove the outside pick-up away from the wheel face.
definitely a biiig plus.





 

 


 

[mmagliaro]

Victor, I totally get it on the friction issue.  Yes, concentrating the contact surface just on a point
on the axle end will by definition not allow as much braking becuause of the small surface, and yep,
I can see how that allows us to put lots of weight in an axle-end tender to get more certain contact,
and still not cause the wheels to drag.

I don't see why an 0-8-0 wheel lifting up over uneven track should cause the sled to lift its pressure off the
other wheelset in that truck.  Of course, as you hinted, the sled definitely has to be loose in the frame.
It has to be able to rock, to and fro, so that it stays in contact with both wheels as they go over uneven surfaces.

I am going to check this.   They do seem loose, but I will check to make sure that lifting a wheel off the rail with an Xacto
point doesn't make the other wheel lift.  Of course, if it removes pressure, but doesn't lift the other wheel, that would
also be bad and would be almost impossible to notice.

Thanks, Victor.  Interesting.  Your line of reasoning makes sense to me.

[victor miranda]

Hi Max

I am not sure why the axles in the shorter truck like the lifelike 0-8-0
tend to lift, it is only that I see it happen.

the cups the axle points ride  might be tighter than the hudson.

try to carve the cups so the wheelsets go up or down a bit more.

the sleds may flex enough to follow track and the wheelsets don't.

another possibility is that when the sled is lifted the flex we see
may get absorbed.  think; the thumb gets held somehow.

victor

[craigolio1]

Thanks Max!

I would not have thought to look at the pick-ups.
The amount of corrosion is pretty bad.
Now that you have clean this off and sanded it,
I suspect this will corrode again and maybe even faster.

Is there something that you can coat these pick ups with
that will protect from corrosion?
Max-lube (a.k.a. Neolube)?

What about a little of that stuff electricians use to coat aluminum wire connections. The tube I have is called No-Lux. Anyway it is supposed to prevent corrosion and is electrically conductive.

Craig

[mmagliaro]

If you mean "No-OX-Id", that and products like it are not conductive.  They are supposed to prevent corrosion,
but they do not conduct electricity themselves.

I've tried that stuff on track, because people swear by it.  After a month or so, I saw no difference between stretches of track
treated with that stuff vs track just left on its own to the elements.  Both had to be thoroughly cleaned by hand before
trains would run on it.

[peteski]

If you mean "No-OX-Id", that and products like it are not conductive.  They are supposed to prevent corrosion,
but they do not conduct electricity themselves.

Thank you Max, this type of misunderstanding the properties of these products is a peeve of mine.  Same with Conduct-a-lube from Atlas - it is not electrically conductive.

[victor miranda]

Hi peteski,

I can imagine you are expecting me to post another explaination.

so I attempt this again...

I am not sure how you would define conductive.
so lets see if copper is conductive
air is not and
silicon and carbon can vary depending on how it is formed.
the varying.... is resistance and lots of things have different levels of resistance...

carbon dust is often used as a resistor
(I mention it because I want you to know that I know.)
crystallized carbon is a diamond and I have read that diamonds are quite conductive.
If I ever get one, I'll test it....

now lets talk oils
I can state I do not think oil is conductive.... usually.
I know that if will form a film between two surfaces
keep them from touching and thus act as air does, little conductivity.
so when oil forms a layer or film between metals, the resistance is high.

I am pretty sure you and I agree this far.

now these people make a grease that is conductive.
http://www.nyelubricants.com/electrically-conductive

so we know it is possible to get oil to conduct while it does the job of lubricating.

here we go into the hard part.

I have to assume you know how capacitors and field effect transistors work....
the charge can affect the conductivity. you may have other ways you'd prefer to say that.

if you build a capacitor with a very thin dielectric film...
what happens as the voltage goes up?
eventually the charge in the dielectric will overlap the
field from the opposite side.
Then.... like the FET, current will flow.

from here I am stating my understanding of the technology
found in conduct-a-lube and bulb-grease.

They are intended to be lubricants AND corrosion protection
as well as having additives that make them pointedly bad dielectrics.
so they allow current to flow with little resistance.

I can't find anyone who will put on the Web, what the additives are however...

victor

[mmagliaro]

Well, I don't know about conductalube or bulb grease, because I have never used either.  But
that no-ox-id, I do have, and it definitely doesn't conduct electricity.   It is a complete "open" on an ohmmeter,
and if I try to complete a circuit through it with a GOW bulb, nothing flows.

Victor, if your idea is that, like a capacitor with a bad dielectric, the grease layer should "break down" and let current
flow at some voltage, I don't know where that break-down point is, but for no-ox-id, it's more than 12 volts.
I've tried it with a little tab, or a thin smear on a card.
Maybe it would actually conduct if I had a micron-thick layer between two metal surfaces, (more like a capacitor)
but I have no way to confirm that.

(and as a thread-drifing aside, I did try no-ox-id on track.  I cleaned 4 yard tracks in a yard, made sure trains ran well on
all 4, then applied no-ox-id to 2 of them, and then just continued on with life... when I needed to clean track again, I tested the
4 tracks and none of them seemed any better than the others.  They all needed to be hand-cleaned to make them
usable again.  So at least for track cleaning, I think it's just another "snake oil" that doesn't really help).