Lineside Chain Markers (?)

[The exile]

Whilst travelling on the Chessington branch on Saturday I noticed small yellow numbered markers stuck into the ground lineside, which appeared to be "chainposts" (as the ones either side of a 1/2 mile post were 39 and 41). Where I first noticed them they appeared to be at one chain intervals; at other places they appeared to be at 5 chain intervals. Are these a) standard [not aware of ever seeing them elsewhere!] and b) permanent - or are they only there in connection with some kind of works taking place (if so, what and why?)?

Thanks in advance to anyone who can provide information

 

[Bald Rick]

Not unique but not particularly common. Likely to be permanent.

 

[Need2]

Are these a) standard [not aware of ever seeing them elsewhere!] and b) permanent - or are they only there in connection with some kind of works taking place (if so, what and why?)?

Do you mean any chain markers per se or ones spaced at 5 chains?
If it is the former then they are very common (unless p-way have removed them). They are also 99.9% of the time situated in the cess in the down side.

 

[alxndr]

How common they are depends where you are. I've never seen any here, our preference being to paint chain and half chain on the web of the rail.

 

[2192]

I noticed these years ago, particularly on inner London ex SR DC lines. But Docklands also has permanent numbered 20 metre markers set in the four foot way, and I heard a staff member refer to these as measuring "the chainage". So we seem to have both imperial and metric chains. The difference is small.

 

[edwin_m]

I noticed these years ago, particularly on inner London ex SR DC lines. But Docklands also has permanent numbered 20 metre markers set in the four foot way, and I heard a staff member refer to these as measuring "the chainage". So we seem to have both imperial and metric chains. The difference is small.

Chainage is general engineering terminology for measurement along a line of route. Design in the UK is universally done in metric, but other units may be shown on markers for operational consistency.

 

[CEN60]

Chainage is general engineering terminology for measurement along a line of route. Design in the UK is universally done in metric, but other units may be shown on markers for operational consistency.

The East Coast in Scotland has KM markers as well as mileposts!

For the record and just to confuse things - We have imperial mileposts, surveys are now done metric m, speed in the sectional appendix in mph, distance in the appendix is Miles & chains, design chainage is in m - (speed again in mph), track radii in m & cant in mm. (A metric / imperial nightmare)!!!

 

[FrankOwen]

On a tamper operating shift I'd use miles, chains, metres, millimetres, half chords and yards.

Start/end of mileage was miles and chains.

Total distance tamped was yards.

Geometry was inputted in half chords (10m)

Lift and slue was in millimeters.