Saturday, September 5, 2015

Accuracy

I'm constantly amazed at the kindness and generosity of people I've got to know through this, and my other, blogs. Over the last year I've been given a set of track gauges by Paul and Iain has sent me some offcuts of Palight to experiment with as well as sharing numerous research photographs to help with my Welsh slate quarry wagon models. To that list I can now add Bobby who has kindly cycled out to the bridge on Duchal Moor to take some research photographs and to run a tape measure over numerous bits of the bridge. I'd already been using one of Bobby's photographs of the bridge to help with the model but this new set shows so many details that I'm going to be able to really enrich the model.

I'll keep most of the photos back for now and show them as I replicate the details, but here is how the bridge looked yesterday lunchtime.


So given I now have some measurements how accurate is my model? Well lets start with the sleepers as they were the first thing I modelled. My best guess from the photos was that they were approximately 2' 9" wide, but I modelled them as 3' due to the slightly heavier, and hence wider, rail I was using. Rather than trying to hand cut thin strips of wood I used OO gauge sleepers from C&L Finescale cut down to 12mm. This meant my sleepers were modelling 3' wide, by 10" across, by 2.4" deep. Bobby measured them yesterday at 90 cm by 25 cm by 6 cm, which when converted to feet and inches gives 2 feet 11 7⁄16 inches by 9 27⁄32 inches by 2 23⁄64 inches. So my original guesstimate of 2' 9" wide was a little out but the actual width I modelled, 3 feet, was pretty much spot on as are the other dimensions.

The two other main measurements are the span of the bridge and the height of the concrete block supporting one end as these basically set the dimensions of the diorama. I've ended up with the bridge spanning a scale 14' 3" whereas Bobby measured it as about 5m or just over 16 feet, so mine is a little bit short but not by much. The concrete support measured out at 1.6m tall by 1.33m wide and 75cm deep or roughly 5' by 4' 4" by 2' 5". The block I cast was based on measurements of 5' tall by 3' wide by 1' deep. I got the depth badly wrong due to not being able to see exactly where the block stopped and the stone embankment started. The height is spot on though even if the width is over a foot too narrow.

Given I was originally working from just a few photos I don't think I did too badly and the measurements are close enough that the difference won't alter the look of the model which means I don't need to go back and change anything fundamental.... phew!

4 comments:

  1. Pretty close to size then! Should anyone quibble just mumble something about 'selective compression'...

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    1. Yes I'm pretty pleased with how accurate measuring from the photos was. There are a few details I've got wrong which I'll cover in future posts as I think most are fixable without major surgery. If anyone quibbles with the basic dimensions then I'll just blame the spade -- when you dig a large chunk out of the ground it always gets a little squashed and distorted :)

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  2. Interestingly I remember thinking that the sleepers had more green on them in the original photo so your less varied ones may now be more realistic.

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    1. I'm now worrying that my sleepers are too dark given that these are almost white, but as you say at least the look quite uniform in these newer photos. I guess it will partly depend on what the weather has been like recently and we've had a reasonable summer.

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