So, having arrived at a much better approach to painting rusty surfaces I've now turned my attention to the track, specifically how I'm going to affix the rail to the sleepers. The bridge I'm using as inspiration for my entry to the Dave Brewer challenge, which is still a secret for now, uses a fairly light rail held to the sleepers using metal spikes.
All the track I've hand built before has used copper clad sleepers and I've simply soldered the rail in place. Clearly this won't work for rail held down by spikes. So firstly I'm going to use sleepers made from plywood (hence my experiments at painting wooden sleepers) but more importantly I need a source of spikes that will hold the rail in place. My intention is to use code 40 rail, which is pretty small, and I haven't been able to find anyone who sells spikes for such small rail. What I did find though was a series of articles in NG&IRM Review by John Clutterbuck (which were republished in 2008 as a free download) about making track. While John models in 7mm scale using larger rail, he happens to make his own spikes from..... staples.
The approach I've taken mostly follows John's description but with a few changes to take into account the smaller rail size.
I bought the smallest staples I could find but they are still made from quite a thick metal (about 0.45mm) so having used masking tape to keep them together I filed the edges down a bit to make the corner a lot thinner (I had to use diamond files to really make much impression on the steel). Once I'd filed down both sides I used a set of track cutters to cut off the legs of the staples keeping just a tiny amount of the curve. All the spikes were then separated from each other before soaking for about 5 minutes in nail varnish remover (the stuff I "borrowed" from my wife is acetone free but I'm guessing acetone would also work) to ensure the metal is clean and that the plastic coating applied to staples has come off; you end up being able to see the bits of plastic floating in the solution. The spikes were removed from the nail varnish remover (a magnet makes this nice and easy) and dried before being soaked in Carr's metal black. They turn black almost instantly if they are nice and clean but again I left them for about 5 minutes, before removing and drying them.
I still need to figure out the best way of actually using the spikes to fix rail to sleepers but for a quick test I drilled a small (0.45mm) hole and pushed a spike through the sleeper, added the rail so I could accurately drill a second hole for the second spike. Once both spikes were firmly pushed through I held them in place with a drop of superglue added from below. Once this had dried I cut off the excess spike and filed them flush with the bottom of the sleeper.
For a first attempt at making and using rail spikes I think this has worked well.