Digitizing, errors, lost pieces
I am doing the track for the Grafton to Parkersburg line which would be a natural extension to the B&O west end and I have noticed some things. One of our colleagues sent me a track chart with a 1983 revision date - the line was abandoned in 1985. By 1983, I had been employed by Chessie System in Huntington, WV for 2 years, but most B&O engineering was still in Baltimore. I have found with this chart & by careful digitizing from Google Earth a few discrepancies or errors. For one, the digitized line is about 5 meters north of where it obviously should be in the TSRE route because in the route, terrain generated by DEMEX, several tunnels were daylighted in 1963 leaving deep cuts and the track should be more or less centered in these cuts, so I move my track south of the digitized line to compensate. Usually the move is 5 meters or less.
Secondly, even doing that I find that some curves are not correct on the track chart. For example a curve just west of mile BA-354 is shown as 6 degrees, 58 minutes, so I substitute a 7 degree curve for that but to match the digitized line requires a 8 degree curve. Nearby there is a 8 degree curve so activities aren't affected by the "adjustment". I will point out that the values on the track chart were probably correct when the chart was first drawn but over time, and especially with SD type locomotives (6 wheel trucks) curves tend to change shape and usually the high end, if the curve is on a grade gets sharper, while the low end may reduce a bit. We noticed this in long ago 1965+ on the Southern Rwy.
And lastly, I did fret about pieces falling off the earth when the terrain object was turned off but then Eric suggested editing the world file to find any pieces with a negative "Y" parameter and in doing so I found that world files done by TSRE are not compressed, or at least I may not have a parameter set to do that. To find world files with stray items, I am bringing the route up in Track Viewer and just jotting down the files (i.e. squares seen on Track Viewer) with stray items in them. Of course one wants to back up the route before doing this editing. Now when we find these pieces with a negative "Y" parameter, we cannot just delete them since they do have a track database entry. So change the negative value to zero, or what works better for me, a small positive value such as "5". Then bring the route up in TSRE and select the orphans you find. Hit the "Z" key to detach them from the track database and then delete the piece. I dare say I will have a hundred or so when I complete this 120 mile route or so, maybe more and then at some future time I will lay additional track for the Shortline and a few other subdivisions.
If I have any regrets it is in not starting to use TSRE sooner but then there is an advantage in that all the ones that went before, solving a lot of problems the rest of us do not have to be troubled by.
J. H. Sullivan
Secondly, even doing that I find that some curves are not correct on the track chart. For example a curve just west of mile BA-354 is shown as 6 degrees, 58 minutes, so I substitute a 7 degree curve for that but to match the digitized line requires a 8 degree curve. Nearby there is a 8 degree curve so activities aren't affected by the "adjustment". I will point out that the values on the track chart were probably correct when the chart was first drawn but over time, and especially with SD type locomotives (6 wheel trucks) curves tend to change shape and usually the high end, if the curve is on a grade gets sharper, while the low end may reduce a bit. We noticed this in long ago 1965+ on the Southern Rwy.
And lastly, I did fret about pieces falling off the earth when the terrain object was turned off but then Eric suggested editing the world file to find any pieces with a negative "Y" parameter and in doing so I found that world files done by TSRE are not compressed, or at least I may not have a parameter set to do that. To find world files with stray items, I am bringing the route up in Track Viewer and just jotting down the files (i.e. squares seen on Track Viewer) with stray items in them. Of course one wants to back up the route before doing this editing. Now when we find these pieces with a negative "Y" parameter, we cannot just delete them since they do have a track database entry. So change the negative value to zero, or what works better for me, a small positive value such as "5". Then bring the route up in TSRE and select the orphans you find. Hit the "Z" key to detach them from the track database and then delete the piece. I dare say I will have a hundred or so when I complete this 120 mile route or so, maybe more and then at some future time I will lay additional track for the Shortline and a few other subdivisions.
If I have any regrets it is in not starting to use TSRE sooner but then there is an advantage in that all the ones that went before, solving a lot of problems the rest of us do not have to be troubled by.
J. H. Sullivan