The String Line

Our last report of progress centered on the rough planting of stools for the rodding run. We had dug holes at regular 9' intervals to approximately the correct depth, and deposited concrete stools into these excavations. 

No need for a gym membership.

Next comes the process for aligning and levelling them up: the straighter the rodding run, the easier it will be to operate as friction and strain is minimised, so the incentive is there to do it really well, once, and not have to keep coming back to alter it later on!

First of all, we set the two ends of this stretch of rodding: the alignment is taken from the Tebay line, whereas the level is taken from the (slightly lower) Penrith / Eden Valley line. It had to be this way around, as the EVR line will be slewed slightly later on as part of Permanent Way (track) work associated with the project. With the Cumbrian weather having filled the stool holes, baling out was first required!

Bailing Out

With the ends set, we borrowed a set of target boards from the P-Way tools: these are used to level up rails, especially when dealing with dips. One end has a horizontally-striped black and white board, the other end has a slot through it. The middle board of the three needs to align through the slot with the stripe for levelling to be correct. We couldn't use a laser level here as the trackbed falls towards the station, and the rodding needs to follow it...

Black & White target - note the means of fastening it down!

This matches the heights all along: we had 2 rail offcuts instead of the 3 required!

The view through the slotted board 

By using this, in conjunction with lifting and packing the stools, we set up several of the stools before changing technologies to use a string line to set the intermediate stools up correctly.

Setting up the string line to get all the stools aligned perfectly: this takes out any
slight variations in the rail from which we worked. The Mark 1 eye ball prevails!!

Rodding going in!

A big team a week last Tuesday saw all 15 of the rodding stools (which is about half the total required) levelled and aligned, before having the first 25 A-frames bolted on, and the first 5 lengths of rodding assembled.

Good Rod.

Thanks for reading and we'll be sure to update you very shortly with more progress.

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