Graphite Treatment to Rails.

[melmerby]

On 22/01/2020 at 23:59, Dagworth said:

 

On a commutator the gaps get constantly refilled with carbon as they pass a brush twice every revolution of the motor.

 

Andi

Some motors don't have gaps, they have solid coms with insulation material filling the gaps .

[The Johnster]

I have applied a graphite block to the entire layout and running has not suffered; it is, if anything, a little improved, and it has now been 5 weeks since I applied it and there has been no need for track cleaning.  No problems with wheelslip.  

 

I'm cautiously regarding this as a success!

[Free At Last]

I bought a stick of graphite on first reading this thread to give it a try.

I began rubbing it on the rails in front of a loco running on dcc to see if I could see any improved running and noted the loco began running slower then I quickly had to let go of the graphite stick.

Duh. Dumb senior moment.

[Barclay]

A little graphite rubbed onto the backs of the tyres, if that's where your pickups bear, can work wonders too. Reduces friction and encourages electrical continuity.

[Rockalaucher101]

33 minutes ago, Barclay said:

A little graphite rubbed onto the backs of the tyres, if that's where your pickups bear, can work wonders too. Reduces friction and encourages electrical continuity.

That's a brilliant idea. Might even work on some of the older split chassis models seeing as you cant really lubricate the wheel sets

[Harlequin]

How graphite actually works - From another thread:

  

On 10/06/2020 at 17:48, Harlequin said:

Can I just follow up on this a little bit? I really want to know what the Graphite actually does!

 

So Mark, are you saying that the graphite is primarily an oxidation retardant? And the fact that it is conductive is what allows it to be used in this context?

 

Does it serve any purpose in preventing dirt building up above it, or in repelling dust? If not, then won't you sill get interruptions in pickup due to those things and have to clean the track to get rid of them (and then redeposit graphite again)?

 

 

On 10/06/2020 at 18:10, FoxUnpopuli said:

Quick answers to Phil's qs.

 

Oxidation retardant: Yes, and yes, this is because it's a thin coating over the rails that is an oxygen barrier that happens to be conductive.

 

Preventing dirt or dust buildup, technically no - although dust won't 'stick' to graphite as well as it would cling to surface with more friction (think of waxing your car) but most 'dirt' on the rails of Nickel Silver track is corrosion anyway.

 

If your track is heavily dusted or dirtied (from say, plaster dust from renovation work) then unfortunately yes, you will need to physically clean your track - probably more a vacuum cleaning exercise.  If you've graphited the rails, further cleaning might be simply a dry felt pad - a Hornby or Dapol rail cleaner - run dry under light pressure. 

 

Further discussion - selected from a Google search: https://model-railroad-hobbyist.com/magazine/mrh-2015-05-may/fight-dirty-rails-with-graphite

 

Edited July 29, 2020 by Harlequin

[Michael Edge]

Running the graphite pencil along the rail head seems to perform this cleaning function at the same time - as long as it's just loose dirt.

[Pacific231G]

23 hours ago, The Johnster said:

Condensed water in the cylinders must be got rid of because it cannot be compressed and will burst the cylinder ends as the pistons close up to them.  Water will of course condense in the cylinders every time there is steam left in them when the loco is taken out of gear, such as standing at a platform awaiting the right away, so this practice has ruined many a photographer's patiently waited for perfect shot...

 

Slipping is not uncommon when starting a heavy train on a curve and an up hill gradient, which is the case at Bridgnorth, and may be compounded by brakes on the train being slow to release, though this should not be an issue with a steam loco.  Pacifics are particularly prone because the adhesive weight, the weight of the loco that bears down on the driving wheels, is spread to the trailing pony wheels in order to allow a wide bottomed firebox to be used to provide sufficient heat to keep those 3 cylinders supplied with steam when the loco is working hard.  The trick is to be gentle with the regulator and to keep the loco moving; if you lose momentum you are back to square, or in this case platform, one.  You see the loco's steam brake being applied after the first unsuccessful attempt to get her moving, to stop the spin.  

 

Sanders might have helped, but increase the wear on tyres and cause damage to the railhead.  If you'd ever seen a Britannia trying to get a 16 coach Red Dragon on the move at Cardiff General in the 50s, you'd realise that Taw Valley doesn't do that badly!

Is that why the GWR/WR didn't use Pacifics? (Great Bear apart)

 

When I was closely observing the last years of steam at Oxford (and, to the annoyance of my friends, never writing down any numbers) the Bulleid Pacifics could be relied upon to slip while pulling away but the Castles and Halls rarely did.

I used to like having the steam from the cylinder drains in my photos. They seemed to add to the atmosphere and the sightof a steam locomotive emerging from a cloud of its own steam was magical.  (And yes pendants, I know it was actually  water vapour and not steam!)

Edited July 29, 2020 by Pacific231G

[melmerby]

58 minutes ago, Pacific231G said:

Is that why the GWR/WR didn't use Pacifics? (Great Bear apart)

 

 

The GWR used 4-6-0s because they could get away with a narrow grate with their high calorific Welsh steam coal*.

A useful side effect was the all the tractive force stayed on the driving wheels when starting.

 

*AFAIK They don't do too well on Yorkshire clag!

 

I remember the Kings & Castles leaving Snow Hill platform 7.

They were the fastest getaways I can remember in steam days as they never slipped and put all the power down right from the start.

 

Edited July 29, 2020 by melmerby

[The Johnster]

The GW's avoidance of Pacifics was a combination of the availability of Welsh coal which enabled the use of 4-6-0s that were as good as pacifics (so long as you could get Welsh coal for them), and the poisoned chalice inherited from the South Devon Railway, which was laid out for atmospheric traction by that nice Mr Brunel, who was like the little girl and she had a little curl right in the middle of her forehead. in that when he was good he was very very good, but when he was bad...

 

Very steep banks in both directions, and for Plymouth trains they were in just the wrong place in both directions; up trains had not yet warmed up properly and down trains were likely to have almost burned through their fires just as the heavy slogging up the banks was needed.  The surer traction of a 4-6-0, which loads all of it's tractive weight on to the coupled wheels and none to a trailing axle, is an advantage in this situation.  

 

Similarly, in South Wales, there were notable banks west of Cardiff that benefitted from the grip of the 4-6-0s over pacifics.  Neath on the down, in particular, requires a steep climb around a 180 degree curve directly off the platform.  The Birkenhead route gets hilly after Shrewsbury as well.  It is for this reason that, Swindon having seen no advantage in pacifics following Great Bear, which I believe ended up on Oxford out and back work, that the oft-referred to Hawksworth/Mattingley pacific never materialised and indeed was never developed much beyond cigarette packet general arrangement outline drawings.  The 1948 exchanges did nothing to suggest to the WR that they needed a rethink, nor to anyone else, for that matter (there was no order for Kings on the KX-Leeds or Bullieds on the Highland, for instance; everybody just carried on as before).

 

Pacifics are much beloved of enthusiasts; they have the cachet and were used on the top link services of the companies that used them, but brutal reality is that they were only used where fares generated allowed a liberal attitude to coal consumption, and were arguably not needed to the extent they were built on the Southern.  The GW in the late 50s looked like and in some ways was a 1920s railway struggling with modernity, but the locos pulled the trains to time, something that could not always be said of the WCML of the day, despite the capability of it's big engines.

Edited July 29, 2020 by The Johnster

[Mick Bonwick]

Did the GWR use graphite on their rails, then?

[melmerby]

1 hour ago, The Johnster said:

 

Pacifics are much beloved of enthusiasts; they have the cachet and were used on the top link services of the companies that used them, but brutal reality is that they were only used where fares generated allowed a liberal attitude to coal consumption, and were arguably not needed to the extent they were built on the Southern.  The GW in the late 50s looked like and in some ways was a 1920s railway struggling with modernity, but the locos pulled the trains to time, something that could not always be said of the WCML of the day, despite the capability of it's big engines.

And Hornby!

 

In the 1950s there was talk in the railway press about the WCML being short of top link engines (e.g. 8P Pacifics) and the ECML having a surplus such that it was suggested that some top Eastern motive power could be moved West.

Whether it ever became anything serious to the point of being officially looked at I don't know.

Would have been nice to see some Peppercorn A1s being thrashed down the Trent Valley line.

 

IMHO Bulleid's Light Pacifics (WC/BB) were definitely an over indulgence.

[melmerby]

4 minutes ago, Mick Bonwick said:

Did the GWR use graphite on their rails, then?

No, they put it in the firebox! (well almost)

[rab]

6 minutes ago, Mick Bonwick said:

Did the GWR use graphite on their rails, then?

I had noticed the severe case of thread drift!

[adb968008]

On 28/07/2020 at 13:44, brian777999 said:

 

What is causing the wheels to slip like that 

Bad design work by an eccentric locomotive designer.

 

its a small boiler with high output, sitting on as many powered wheels as there are unpowered wheels.

if it were a 2-8-2, Bulleids light Pacific's would probably be much better adhesively, and of course be a Bulleid light mikado. They also wouldn't have been subject to as much wartime scrutiny and been a much more agreeable loco, much like the German BR41 or the PKP pt31/47 or the SNCF 141. 8 driving wheels would have given it much better weight / power ratio, especially for heavier trains or surrey style hills, whilst still having a very fast turn of speed, and being efficient on shorter trains, being balanced for tender first workings too.. (which they were known to do).

4-6-2’s need big boilers.. were 72xxx Clans any better ? 
35028 Clan Line And 35005 Canadian Pacific seem to have better grip on its feet when out and about than 34016/34067 or 34046 have in recent years... never mind everyone elses 4-6-2’s which don't have the same rotational challenges.

 

 

Edited July 30, 2020 by adb968008

[The Johnster]

But 8 driving wheels of a size sufficient for reasonable express passenger speed without murdering the track, within the UK loading gauge, something the eccentric designer was more familiar with than most from his intimate involvement with the P2s,  have longer wheelbases than light pacifics, and if you want them to have the same route availability, you’re back to the small high output boiler, so there isn’t any more adhesive weight and possibly less. 
 

I don’t know if the Clans were any better, but they were well regarded by Carlisle crews on the Port Road, acknowledged to be particularly difficult and challenging, and on the S&C.  

[ejstubbs]

On 15/01/2020 at 09:33, Fat Controller said:

Bear in mind that the differing hardnesses of pencil are due to different quantities of an inert filler (a clay of some description). It would be interesting to know which grades of pencil have the least, to mimimise surface contamination.

 

https://en.wikipedia.org/wiki/Graphite_pencil#Production: The main components in the manufacture of rods - purified graphite powder and kaolin (a clay binder). Hardness depends on the ratio of their particles. The more graphite - the softer the rod. The hardest pencil contains about 20% graphite, the softest one up to 90%. The 1:1 ratio roughly corresponds to the 3H hardness.

 

According to this Wiki entry, the pencil grading scale runs from 9H to 9B (hard being for "hardness", B for "blackness", allegedly).

[TheQ]

Definitely 9B the softest I use one of these..

https://www.amazon.co.uk/Lyra-4336947169-Graphite-Stick-9b/dp/B0012EXM62/ref=sr_1_4?crid=3FD1XHMQM68CD&dchild=1&keywords=9b+graphite+stick&qid=1596114003&sprefix=9B+graphite+stick%2Caps%2C1061&sr=8-4

[rab]

5 hours ago, ejstubbs said:

 

https://en.wikipedia.org/wiki/Graphite_pencil#Production: The main components in the manufacture of rods - purified graphite powder and kaolin (a clay binder). Hardness depends on the ratio of their particles. The more graphite - the softer the rod. The hardest pencil contains about 20% graphite, the softest one up to 90%. The 1:1 ratio roughly corresponds to the 3H hardness.

 

According to this Wiki entry, the pencil grading scale runs from 9H to 9B (hard being for "hardness", B for "blackness", allegedly).

It's good to see the bobby has routed this thread

off the diversionary track and back on the main.

[57xx]

On 30/07/2020 at 13:29, ejstubbs said:

The more graphite - the softer the rod. The hardest pencil contains about 20% graphite, the softest one up to 90%. The 1:1 ratio roughly corresponds to the 3H hardness.

 

So if I want more lead in my pencil, I should actually be using clay?

[Mick Bonwick]

1 hour ago, 57xx said:

 

So if I want more lead in my pencil, I should actually be using clay?

 

Steady, lad, steady! Remember where you are.

[Phil Traxson]

On 30/07/2020 at 13:29, ejstubbs said:

 

https://en.wikipedia.org/wiki/Graphite_pencil#Production: The main components in the manufacture of rods - purified graphite powder and kaolin (a clay binder). Hardness depends on the ratio of their particles. The more graphite - the softer the rod. The hardest pencil contains about 20% graphite, the softest one up to 90%. The 1:1 ratio roughly corresponds to the 3H hardness.

 

According to this Wiki entry, the pencil grading scale runs from 9H to 9B (hard being for "hardness", B for "blackness", allegedly).

I've been successfully using cheap joiners pencils for the past 20 years, they're definitely into the "B"'s for softness, clean to use, the wide oval "lead" soon forms a groove to fit the railhead with a bonus that it also goes on the inside edge of the rail too, and of course they are available in most bargain stores at about a £1 or so for ten and often include a dedicated sharpener in the pack as well (I'm 50% Yorkshireman). The only problems I have are when well meaning guest operators insist on cleaning my "dirty" track where upon performance rapidly goes down hill, until I run the pencil round again! I can't remember when I last cleaned the track completely.

Edited August 1, 2020 by Phil Traxson

[The Johnster]

Having had good results from an artists charcoal stub I was given, I’m going to try this stuff ; seen in a local cheapo ‘anything emporium’ and as you can see I’m £1.29 down if it’s no use.  Reasoning is that copper conducts leckery, right?  Contains copper powder (which I imagine is copper in a powdered form), graphite, petroleum distillates, and DME whatever that is when it’s at home.  
 

It’s more like a liquid than a grease, sort of a bit like WD40 in consistency, and I’m a bit worried about getting it on plastic or nylon gears, so will try on scrap items before using it in anger on anything valuable like locos, but I sprayed a bit of old track with it last night and the plastic sleepers are fine today.  ‘Petroleum distillates’ sounded to me like something that would evaporate off   quickly, but the track was still wet 2 hours later.  The stuff is clear yellow in colour, and warned to be highly inflammable, which I’d sort of suspected as soon as I saw ‘petroleum distillates’ mentioned.  Doesn’t warn about this in the can, but I’m working to the assumption that a well ventilated environment is advisable. 
 

I’ll post the results of further experiments here.  

[Barclay]

Interested to hear how you get on.  I use this on the car, it's good for preventing squealing brakes and you can put a dab on spark plug threads to prevent them rusting in place. So, less a lubricant and more a way of helping parts to bed nicely together and stay rust free. Mine comes in a tub though and is quite thick so I think it would always stay greasy and would be a bit messy for the railway. 

[The Johnster]

This is in a rattlecan and despite it’s name not really greasy or even all that oily.  My hope is that it will work in a similar way to graphite, evaporating off to leave a conductive coating on the rail head, and perhaps pickups and wheel tyres and backs as well.  
 

Perhaps a mix of tub grease and rattlecan liquid would produce a more suitable consistency for layout use.