Kyle of Lochalsh MPD - track layout

Tell us about your layout, where you put it, how you built it, how you operate it.
John Palmer
Posts: 619
Joined: Fri Jul 15, 2011 11:09 pm

Re: Kyle of Lochalsh MPD - track layout

Postby John Palmer » Mon Jun 29, 2020 2:20 pm

Hi, Martin,

I agree this is a hard one to call, but having engaged in a similar line-drawing exercise I come to a slightly different conclusion. When drawing my lines I try to use the maximum point of contrast in the underlying picture in order to optimise their alignment. In this case my l/h line attempts to follow the outer edge of the stock rail where there is a sharp contrast between rail head and timbers/ballast:
KofL Tandem.jpg

My conclusion is that, whilst the r/h stock rail is quite well aligned in a straight, the l/h stock rail is waving about all over the place! There appears to me to be a quite perceptible reverse curve in this rail between the heel ends of the planing of the two adjacent switch tongues.

I fear this commentary may involve a fair degree of thread drift - sorry, Julian! - but perhaps it has value in illustrating how difficult it can be to capture some of the subtleties in prototype track geometry.

User avatar
Martin Wynne
Posts: 869
Joined: Mon May 14, 2012 4:27 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Martin Wynne » Mon Jun 29, 2020 3:11 pm

Hi John,

Hmm. You are suggesting that heavy locos taking the right-hand road have displaced the stock rail wide-to-gauge on the left? That seems very possible.

It can be difficult to draw accurately along a rail edge in a photo, because of the top corner radius on the rail, and wear patterns on the top surface. Here instead I have drawn along the shadow:

kyle_tandem4.jpg
kyle_tandem4.jpg (310.12 KiB) Viewed 459 times

There is some evidence of a sideways displacement, but it's unlikely to extend as far as the second switch -- the rail doesn't have a chair on the soleplate of that switch.

Looking at the intersecting shadow lines, I still think a set is the most likely explanation for the line of the rails. It will be around 1:100, so it's never going to show up very well.

On the right-hand side I have drawn a chord across the switch. If that is intended to be a ruling curve it is very poorly aligned. It looks more like a deflection to me.

Without an accurate map we can never be sure, I will see how it looks in Templot. But first a boiled egg.

cheers,

Martin.
40 years developing Templot. And counting ...

Julian Roberts
Posts: 898
Joined: Sat Jan 09, 2010 11:33 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Julian Roberts » Mon Jun 29, 2020 6:46 pm

For what it's worth, having tried this several dozen times, I start with a very slight left hand curve from about half way between the water tank and the turntable. to the turnout that follows this tandem - so it's a single sided tandem. I think that when the turnouts are created from the LH curve, there are slight extra bends in the LH rail.

For me the issue is getting the triangle of rails around the centre crossing looking right. I found it difficult to get the 1st turnout crossing sufficiently far back from the 2nd that the wing rails of the first didn't elide into the check rail of the second. This photo shows pretty clearly they are quite separate. YET at the same time getting the 1st turnout to at least fairly closely follow the map outline; at the same time the problem was, where is the switch? - I thought I had it too far from the water tank. In this version that I thought was my last attempt I do have the wing and check rails joining up - though it made me wonder whether these rails would be as long as Templot makes them in this situation.

I didn't try doing it manually, though having successfully tackled the irregular single slip manually maybe I should have done.

I fear this commentary may involve a fair degree of thread drift


Not at all John - I'm most grateful to you and Martin for this forensic appraisal! Though TBH what I could do with from such forensic gurus is whether it's possible to say what angle the "extra" ash road turnout crossing might be!?

By the way, would the timbers remain perpendicular to the "main" LH line. If so I haven't seen yet how to do that.
Attachments
Tandem detail delete 2.PNG

User avatar
Martin Wynne
Posts: 869
Joined: Mon May 14, 2012 4:27 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Martin Wynne » Tue Jun 30, 2020 5:13 pm

Hi Julian,

I've had a go at the tandem by reference to the colour photo. It worked out quite well:

Image

Image

BOX file:
kyle_tandem_45degs.box
(224.39 KiB) Downloaded 10 times

I've rotated it 45 degrees from the OS map to match your posts.

It contains rather more partial templates than usual in order to match the main road, which appears to be a string of straights and curves, and includes a split-deflection switch. In the end I found a 50-50 symmetrical switch produced the closest match (1:64 rotation for a B switch, both switches are B). Having multiple partial templates made it possible to use standard V-crossing angles -- 5.5 , 7.5 , 7.5

I've done most of the timber shoving.

cheers,

Martin.
40 years developing Templot. And counting ...

Julian Roberts
Posts: 898
Joined: Sat Jan 09, 2010 11:33 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Julian Roberts » Tue Jun 30, 2020 9:05 pm

I'm greatly privileged to have half my layout designed by Mr Templot himself! :D

Very many thanks indeed Martin. I haven't opened the file yet not having access to my pc till tomorrow.

Julian Roberts
Posts: 898
Joined: Sat Jan 09, 2010 11:33 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Julian Roberts » Sat Jul 04, 2020 10:16 am

Track plan re-designed to incorporate Martin's bespoke tandem. I've played with the dummy vehicle tool on Templot to make a Black 5 length vehicle (including tender). It "runs" on two bogies so the overhang will be less on curves. With a bit of luck there'll be just enough room for a loco to come up the shed road while another is in the ash road, the length of which depends where I put the coal platform. And there's room in front of the shed doors too.
Attachments
LAYOUT COMPLETE INC M WYNNE TANDEM 4 JULY.PNG
Black 5 next to loco shed.PNG
Black 5 on tandem.PNG
Black 5 on ash road.PNG
Black 5 by loco shed.PNG

User avatar
Noel
Posts: 1312
Joined: Wed Jun 23, 2010 1:04 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Noel » Sat Jul 04, 2020 1:41 pm

Julian Roberts wrote:the length of which depends where I put the coal platform


The coal platform is shown on the map - the black line on the other side of the track to the water tank. It runs from 1/3rd of the length of the tank almost to the turntable. Photographs suggest that the ash road is only long enough for two wagons, so say 40 ft plus the clearance necessary to ensure parked vehicles don't foul the shed exit road.
Regards
Noel

Julian Roberts
Posts: 898
Joined: Sat Jan 09, 2010 11:33 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Julian Roberts » Sat Jul 04, 2020 2:19 pm

Yes Noel, I see now, and the photo at the top of this page shows the same thing if I'd only looked properly - thanks for pointing that out. It was this photo that had me thinking locos were emptied of their ash on this road - https://thetransportlibrary.co.uk/index ... t_id=83407
Well perhaps they did, but blocked that RH road from the tandem while they were doing so. Can't see much evidence of ash on most of the other photos that have appeared on this thread*. Perhaps there was a clean up in advance of the photographers arriving. Does anyone know, would ash from the Cummings Clan goods locos, and Black 5s, have been emptied vertically down into the pit (situated on the RH road by the shed door)?

* - actually, plenty of ash on the older photos from Jeremy

User avatar
Noel
Posts: 1312
Joined: Wed Jun 23, 2010 1:04 pm

Re: Kyle of Lochalsh MPD - track layout

Postby Noel » Sat Jul 04, 2020 3:21 pm

Julian Roberts wrote:It was this photo that had me thinking locos were emptied of their ash on this road - Well perhaps they did, but blocked that RH road from the tandem while they were doing so


I believe this photo pre-dates the construction of the ash road.
Regards
Noel


Return to “Layouts and Operations”

Who is online

Users browsing this forum: No registered users and 1 guest