RMW "Layout & Track Design" - all change............

[DCB]

It sounds like you have back to back problems, I use Peco code 100 with a bit of set track and a bit of ancient Grafar.  I made a back to back gauge which is a bit of wood almost square section 14.25 mm wide (Measured with a micrometer)  with an axle slot in one end and I check all new wheelsets for a sliding fit before fitting them.  If they are loose I close them up to a sliding fit.  The old Hornby dublo moulded nylon wheelsets are 14.25 mm sliding fit and I have 400 or more so I'm not changing them!  Some mainline /airfix plastic wheels on shouldered metal axles cant be adjusted and the old Triang Hornby plastic an shouldered axles and the metal tyres on plastic axles are just a joke, Curiously the really old two part ones can easily be adjusted with a spacing washer between the two halves.    The old Airfix and Mainline wheels, Auto coach Centenaries etc had knife edge flanges which were really nasty. I rewheeled one of mine with nice split axle disc wheels whoch I used for electrical pickups for the lights but have never managed to find any more since

The problem is tolerances, 14.25mm sliding fit is around 14.5 mm actual,  Judging a tight fit with a digital caliper is just too complicated for me

To really do it properly (GWR style) make two gauges one 14.25 mm and one 14.75 mm, if a wheel set fits the 14.25  and does not fit the 14.75 it's fine. 

Edited January 22, 2016 by DavidCBroad

[DCB]

Another cause of derailments on second hand coaches is where they have been lowered, old Triang/Hornby coaches sat 1mm too high and many people lowered then by cutting the bogie pivot tower down, the coupling rivet then fouled the headstock making the bogie stiff to turn on uneven track.

[Chimer]

Re Video - my efforts are not worthy of YouTube !.....................

 

Re wheels ............... although my stock is not new most of it is "modern/as new" predominantly E bay sourced Hornby with some Mainline - some wagons are only a couple of years old - ironically its the better quality/newer stuff which bounces more possibly because its lighter? - I will check your measurements next and report back - thanks.

 

I didn't know changing wheels was normal I guess here we go on another steep learning curve - wheels, couplings - uncoupling methods - point motors etc etc etc....................!

 

All good fun.

 

Thanks

 

Hi J

 

it's not - not with Code 100 track which is pretty forgiving stuff.  I get odd derailments due to couplings locking up but the only thing I've got that simply won't look at my Code 100 electrofrog (which i don't think matters) points is a very old Triang Hornby Jinty.  If you're having problems with lots of stock I think I might first suspect the tracklaying, especially if the problems occur most frequently at some rather than all turnouts.  Does the stock that doesn't derail go through perfectly smoothly? 

 

I do hope I'm wrong and your new wheels solve the problem though ...

 

Cheers

 

Chris

[jon_1066]

I suspect it may be the track pins - they can distort the track slightly which then causes the points to not sit flat and therefore cause problems with stock.

[halsey]

Hi David,

Not sure I get this - any chance of a picture?

[halsey]

Hi all,

 

I've been doing more running this afternoon and definitely the worst offenders are the 3 carriages and a Palethorpes 6 wheel wagon curiously all with 14.1 wheels and all the same plastic square section axle type which is the common denominator.

 

Good runners run OK through all the track, track pins have been tapped home with care, so am not thinking at this moment that its track laying problems - I have a mixture of types/designs of points all code 100 NO set-track (they were all sold on weeks ago!) and its only the straight small radius LH and RH ones causing any issues.

 

Lets hope wheels do the trick

 

Thanks for the quick responses to my cry for help - all good stuff.

 

J

[DCB]

A drawing of a go/no go back to back gauge for 14.5mm nominal back to back.  I have only done the 14.25mm end so far but will file up the other end(s) tomorrow evening, I only thought of this thanks to Halsey's posts.

[ejstubbs]

I've been doing more running this afternoon and definitely the worst offenders are the 3 carriages and a Palethorpes 6 wheel wagon curiously all with 14.1 wheels and all the same plastic square section axle type which is the common denominator.

 

I had a some coaches with those square section plastic axles - IIRC they're Hornby RailRoad models.  Those plastic axles carry plastic wheels with metal tyres.  IMO you can't make the situation any worse by swapping them out for better all-metal wheels and axles.

 

The point a couple of folks have raised about checking that the bogies are free to rotate is a good one.  I don't know anything about the six-wheeled wagon but I believe that these usually have some articulation on the middle axle in order to allow the wagon to traverse Setrack-radius curves.  If it is supposed to be articulated and is somehow not functioning correctly then I imagine that could cause problems similar to a bogie that isn't rotating smoothly.

[mightbe]

In the future, I suggest not using track pins at all--even if done carefully they can still distort track. Try PVA. It's water soluble if you ever need to change anything. Even totally dried and crusted glue that was applied years before will dissolve in water. Obviously, don't use so much water that the benchwork warps.

 

But yes, replace the plastic-axle wheelsets. The plastic can distort and leave you with wheels that aren't parallel, etc. Better to just replace them and move on. The track is probably fine. It's code 100. For what you're running it will serve you well--just make sure that the wheels you use are good quality, all-metal ones. The Hornby ones are excellent for that.

 

Quentin

Edited January 22, 2016 by mightbe

[halsey]

Thanks once again - LMS coaches and Palethorpes wagon now sorted - new Hornby all metal wheels now on order for remaining rolling stock - what a difference!

 

Cheers J

[halsey]

Hi all.

 

I bet you've been waiting for this one...............I now have an electrical/faulty point problem...................................

 

On the attached sketch of my upper branch line station (all wired as one section as per the earlier posted drawings) should there be an isolation break on the crossover (6/7)?

 

In use the 2 lines don't seem to isolate one from another as I would expect when the points are logically set (code 100 insulfrog) - the crossover seems to create "feedback" or might I have a faulty point at point 6 or 7?

 

"F" means feed - 2 connections

 

A bit more explanation - regardless of how point 2 is set the lines between 2 and 7 and 3 and 6 can both be live dependant on how 6 or 7 are set??

Edited January 27, 2016 by halsey

[Chimer]

Something strange does seem to be going on, what you are expecting is what I would expect too, i.e.:

 

With point 2 set right, 2-7 should be isolated regardless of the setting of the 6-7 crossover.  The bit of 2-7 beyond 7 should be live, and the bit of 3-6 beyond 6 isolated, if the crossover is set to cross over (!).  

 

With point 2 set left, 2-7 should be live and the road through 3 isolated, again whatever you do with the crossover. The bit of 2-7 beyond 7 should be dead if the crossover is set to cross over.

 

I cannot find any explanation for electrickery getting to both rails on either of those roads with point 2 set against them........ others may!  Equally I don't know how a point could "fail" to isolate - lots of people expect them to fail to conduct over time.  Logically this problem would have to be caused by point 2 - a stray trackpin maybe?  And IRJs on the crossover couldn't make any difference as far as I can see.

 

Good news about the wheelsets, anyway!

 

Cheers

 

Chris

[Nearholmer]

I'm out of practice with 2-rail (3-rail is a lot easier!) and never used insulfrog points when I was in practice, but ........

 

Aren't these points "self isolating" only when they are fed from the "toe", meaning that 7, 3 & 4 can all provide "back door" connections from Fa and Fb in various circumstances?

 

Which would cause exactly what you are experiencing.

 

I think I would isolate both rails between 6+7, and between 3+4.

 

(Await a second opinion before setting to!)

 

Kevin

[halsey]

Hi Chris

 

I will follow your itinerary, check what happens and report back sometime tomorrow.

 

Thanks

 

FYI - wagon wheel sets now en-route - total cost to remedy all issues - £38 - £1.50/item - disappointing but not too painful.

Edited January 27, 2016 by halsey

[Chimer]

Given Kevin's thought, I did some drawing showing the individual rails - and now think if point 6 is set to the crossover and point 7 is not, 2-7 will be live regardless of the setting of point 2.  But I can't find a way (yet) of making both rails of the lower line live with point 2 set against it, though at first I thought it might be possible by frigging about with points 3 and 4 to get power through from the headshunt feed.  If I've got it right now, if 6 and 7 are either both normal or both set to crossover, you shouldn't have a problem - and why would you want them mismatched?  I think in real life they would be moved by the same lever.  If you do put IRJs on the crossover, I think you would need another feed to the right of point 7, and if you put them between 3 and 4 you would need the headshunt feed moved to between 4 and 5.

 

Hum ..... I think I've just learned something.  Good here, innit?

 

Chris

[DCB]

To "solve" the problem you need a double isolator between 6 and 7 if the fact 2-7 and 3-6 are live bothers you. Personally it would not bother me. as you would then need a feed to the lower rail beyond point 7 to allow running round as otherwise setting the crossover will isolate the stub beyond point 7 

 

2-7 the top rail is fed from point 1, if 1 is set left (1L) then  2-7 is isolated, if set Right (1R) 1 feeds the top rail of 2-7

If 2 is set left (2L) 2  feeds the bottom rail of 2-7   so 1R 2L and 2-7 is live.

If 2 is set Right (2R)  and 3 left (3L) 2-7 will be dead until 6 is set left (6L) which will feed 2-7  through point 7 (lower rail) and point 1 (upper rail)

 

3-6 The top rail can be fed from 1R and 7 when 7 is set left across the crossover

3-6 the bottom rail is fed from 3 when 3 is set left (3L) irrespective of the setting of 1 and 2.

 

The headshunt feed 4 should be between 4 and 5 electrically but I can't see it affecting 2-7 or 3-6

 

It is all good fun and simpler than electrofrog where back feeds from stabled locos can cause even weirder effects

 

It is much easier with Radio Control (Or Clockwork)

[ejstubbs]

think if point 6 is set to the crossover and point 7 is not, 2-7 will be live regardless of the setting of point 2....if 6 and 7 are either both normal or both set to crossover, you shouldn't have a problem

 

I agree with that, at least in respect of 2-7.  I can't remember whether halsey is working the points manually or by point motors.  If the latter then it would be straightforward to work 6&7 together from one switch - which would, as you say, be the way they would have been worked in real life.  If the points are being worked by hand then the operator would just have to remember to follow the rule.

 

If you do put IRJs on the crossover, I think you would need another feed to the right of point 7

 

I agree with that, too. With IRJs on both rails of the crossover then there would be no way to run a locomotive from 2-6 into the spur beyond 7 (or vice versa) without it - in other words, you couldn't run round!

 

I can't find a way (yet) of making both rails of the lower line live with point 2 set against it

 

Ignoring point 3 for a moment, if point 2 is set for the 2-7 road, and 7 is reversed then 2-6 would be live.  What happens is that the "upper" rail of 2-7 is always live (because it's continuous all the way to the bufferstop beyond point 7).  With point 7 reversed there is also a circuit from that "upper" rail out of the frog of point 7 towards point 6.  Since the corresponding rail on point 6 is continuous, that makes the "upper" rail in 2-6 live as well.  Now looking at point 3, if that is set towards the 3-6 road then the "lower" rail of 3-6 is also live (since the "lower"rail of point 2 is continuous).

 

One way to get round this would be to make sure that point 3 is never set to the 3-6 road when point 2 is set to the 2-7 road.  Following on from the answer to keeping 2-7 isolated, as previously described, you might think that the way to do this would be have points 2 and 3 operate together - but if you did that then you never be able to access the goods yard (oops).

 

In fact, though, operating points 6 and 7 together fixes this problem too, since you would (should) never leave point 7 reversed if point 2 is set to the 2-7 road.  Alternatively - or even additionally - you could put a single IRJ on the rail which emerges from the from of point 7 towards point 6.  Making it a single IRJ would avoid having to have the additional power feed to the toe of point 7.

 

if you put [iRJs] between 3 and 4 you would need the headshunt feed moved to between 4 and 5.

 

I agree with that, too.

 

In fact I'd go further, and say why not run the upper branch as cab control?  IRJs between points 3 and 4, with a separately switched power feed between points 4 and 5.  More IRJs between points 6 and 7, and after point on the 2-7 road, with a separately switched power feed to the toe of point 7.  That way at least nothing would be live when you didn't expect it to be.

 

Come to think, wasn't halsey planning to run the branch "one engine in steam"?  If so then all of this is largely moot...

 

MAJOR CAVEAT TO ALL OF THE ABOVE:

 

I have a stinking cold so my reasoning may well be faulty.  I only decided that I had to join in with this particular debate because the cold woke me up, and then couldn't get back to sleep because of thinking about the problem!

 

Oh, and another thing: I'd have drawn diagrams to illustrate what I'm saying in all the above, but (as anyone who's seen my post on the current Kadee couplings thread can attest) my drawing skills are minimal to non-existent.

 

And finally: sorry about the unnecessary blank lines in my quotes of Chimer's post.  I can't seem to make them go away

 

Right, now I've got all that off my chest it's time to take some more drugs and head back to bed!

Edited January 28, 2016 by ejstubbs

[halsey]

Wow!!

 

If I've got any of this right in my head without being in the shed looking at it - it seems as though a single IRJ (hey don't I sound as though I know what I'm talking about!) between 6 and 7 is the easiest solution????

 

If so on which rail?? (easy to understand detail here please not "toes" etc) and I assume a single won't need any additional switching (as it just breaks a "feedback" circuit) other than that provided by points otherwise that will muck up my control panel!

 

Thanks all - EJ hope you are feeling better soon - what on earth would you have written if you'd been well!!

Edited January 28, 2016 by halsey

[Nearholmer]

ejstubbs

 

My sympathies to you, Sir.

 

Post 238 started out like your 242, but I too have a major cold (or flu,still not sure), and my brain simply couldn't cope!

 

K

[ejstubbs]

I'm going to go a bit Pierre de Fermat here and say that I had a beautifully expressed explanation all written up and ready to post, but then I pressed the wrong button and lost it all 

 

I'll try to re-create it over lunch - I am at work today, despite the cold and the lack of sleep...

[Chimer]

Wow!!

 

If I've got any of this right in my head without being in the shed looking at it - it seems as though a single IRJ (hey don't I sound as though I know what I'm talking about!) between 6 and 7 is the easiest solution????

 

If so on which rail?? (easy to understand detail here please not "toes" etc) and I assume a single won't need any additional switching (as it just breaks a "feedback" circuit) other than that provided by points otherwise that will muck up my control panel!

 

Thanks all - EJ hope you are feeling better soon - what on earth would you have written if you'd been well!!

 

Edit - ignore the first half of this post, I've got it wrong, sorry!!

 

On the upper rail, if you redraw your picture showing both rails - i.e. the rail coming from the frog of point 7.  For future info the "toe" is the end of the point with one track - worth remembering as it makes it much easier to describe things, though nobody seems to use "heel" for the other (frog) end!

 

Cheers

 

Chris

Edited January 28, 2016 by Chimer

[halsey]

OK - thanks all - I'll give it a go!

[Chimer]

I just started to draw this out carefully which made me realise both EJS and I have got something wrong.  The diagram shows how the juice can flow to make the top track live with point 2 set against it.  The black arrows show the directions the points are set, and the red and green arrows the "routes" the feed (red) and return (green) wigglies effectively follow from the main power feed off to the left to make the rails live (this will not do as an explanation for a physics GCSE exam, by the way).  Black rails are isolated given the way the points are set.  An IRJ in the top (red) rail between 6 and 7 achieves nothing; an IRJ in the green rail will isolate 2-7 but also make the runround unusable without a feed beyond the toe (i.e. to the right!!) of point 7, which, unless the feed is switched, negates the point of the IRJ.

 

 

In my view the simplest solution remains to switch 6 and 7 together, to crossover or not.  As I said earlier, why would you want them any other way?

 

I do hope I've not made any more errors ...... I've changed this diagram 3 times already 

 

Chris

Edited January 28, 2016 by Chimer

[halsey]

Hi all,

 

Problem solved - I have isolated the "crossover" with an IRJ on both rails where 6 and 7 join and then added a new feed to the track to the right of point 7 on the runround - all is now as I  initially expected it to be - why do issues always occur on the least accessible areas of a layout - easy job but logistically pretty testing - off to have a shower now!

 

Thanks all.

Edited January 28, 2016 by halsey

[ejstubbs]

Chris

 

Your diagram is correct, and it proves what I agreed with you on before: that to prevent 2-7 being live when point 2 is set against it, you need to operate points 6 and 7 together - just like they would have been in the prototype.

 

The single IRJ is to prevent 2-6 being live when point 2 is set against it.  As I said in my loooong post last night, ensuring that points 6 and 7 are always operated together will prevent this, too.  The single IRJ is just another way of achieving the same thing (I think - as I said, my brain was full of cold last night so if you want to draw that one out and prove me wrong, I'd be more than happy to retract the idea!)  Call it failsafe, if you like - particularly relevant if the points are being worked manually rather than by point motors.

 

Looking at point 7 from the bufferstop ie the toe end, the single IRJ should go on the left-hand of the two rails emerging from point 7's frog.  No additional switch would be required, so the control panel can remain unchanged.

 

I agree with you that a pair of IRJs between points 3 and 4 might be a good idea, together with moving the power feed for the goods yard to between point 4 and 5.  The main reason I think this would be a good idea is that it would avoid any unexpected and difficult-to-diagnose behaviour arising from power being fed to points from the heel end.  A possible side benefit is that it would allow the branch terminus to be run with more than one loco (although not simultaneously).  For example, a loco could be shunting in the goods yard, then isolated in a siding (or even the headshunt) while a passenger train arrives and runs round.  Then, while the passenger train is waiting to depart, the passenger loco could be isolated on its platform and the goods loco could finish shunting the yard and depart with its train.  Again, this would only need the new IRJs and one power feed moved; no additional switching would be required.

Edited January 28, 2016 by ejstubbs