Central Valley Track laying – Part II …
Posted by Ian Millard
On Monday I laid the first lengths of rail down on the Central Valley tie bases.
The first job was to install a short section of transition track between the PECO track and the CV track. This is located about where the train will enter the Temple Court scenicked section from the helix. The transition piece was required due to the different overall track heights between the PECO and the CV track, which was around one millimetre, with the CV track being less.
I managed to find a short length of Micro Engineering code 70 track and this was duly made to fit and feeder wires soldered in place.
In the second picture you will notice quite a bit of adhesive. As the transition section could not sit flat on the foam due to the track height difference, the plan was to have it sit ‘suspended’ in the bed of glue. Liquid Nails was used, but once I had the track in position, I realised I had applied a tad too much glue! The excess glue will be removed with a Dremel ‘burr’ tool once set.
In the image below, I have pointed out that the rail joins are offset. This is similar to what I did when laying the PECO track in the helix. It’s always better to have rail joins staggered, as this helps with the flow of the track and the possibility of a kink is avoided.
I must now mention that the longer bit of rail at the top in the above image was pre-coated with the contact adhesive as well as the few CV ties that it would be glued to. Once it was in position, the rail was held down, located in the moulded tieplates, and MEK applied with a brush to the tieplates to activate the adhesive and make the bond. This will be explained further on.
I could now start laying rail on the CV track. But first I had to come up with a sequence of things to do. At the moment, this is what I have come up with:
1. Depending on the location, the rail needs to be pre-curved. The main reason for doing this is to alleviate the stresses on rail joins where the rail would be under tension and have a tendency to want to ‘spring’ out. The rail is curved using a Rail Roller from Fast Tracks.
The bend can be adjusted to suit whatever radius you have. I found that after a few passes through the tool, I achieved just the right amount for the rail to virtually sit in place on its own.
2. Once the rail has been curved, it is placed in position and a mark made at a suitable location for the feeder wire to be attached. With the semi-hollow nature of the spline roadbed, it allows the feeder wires to be pulled through the foam and spline. These will be hidden by the ballast later on.
So, a short piece of hook-up wire is soldered in place on the underside of the rail.
3. The underside of the rail is now cleaned with Methylated Spirits to ensure a good bond with the contact adhesive.
4. Once the rail is clean, the contact adhesive & MEK mixture is applied as a thin coating using a cotton bud.
5. The same adhesive is also applied to the tieplates on the CV track. Again a thin coating is all that is required and is applied by brush.
Both the rail and tieplates are left to dry for at least an hour.
6. Once the adhesive is dry, the rail is placed in position on the moulded tieplates, held down with light pressure with a small block of wood, and MEK is then applied to the rail/tieplate join with a brush. Keep pressure applied for about thirty seconds then move on. I only do about ten sleepers at a time.
At this point, I am only laying one rail. I’ll probably continue with one rail all the way to the staging yards, then come back and fix the second rail in place. I’m hoping I won’t need to use any gauges as the moulded tieplates form the ‘gauging’.
Overall I am very pleased with how it’s all going. A lot better and easier than I had imagined.
Posted on Apr 22, 2014, in Electrical, Temple Court, Trackwork and tagged central valley model works, cv, cvmw, mek, temple court, tie strips, tracklaying, trackwork. Bookmark the permalink. Leave a comment.