Perhaps experienced O gaugers already know this tip, but for those who don't:
My layout was pure custom built, requiring six or seven custom cut track pieces. Most were short curved sections, in tight areas, which required some "custom made" long track pins, that would easily bend to the radius of the curve when installed. I needed he track pins to be exposed between the track sections for about 3/8ths of an inch to get the track sections together the way I wanted.
I tried a lot of things, including thick copper wire, etc. None of them worked very well.
Then, I went into my closet and found the cheapest wire hanger I could find, from a dry -cleaners. Very thin rod metal and easily bendable.
I cut the lengths I needed, filed the ends down a bit to make them more easily fit into the pin holes of the track, bent them into the curved shape I needed, and used them to hook together the track sections. They slid right in, with just a little resistance. Unlike the very stiff standard pins, I could easily bend the connected joints between two track sections a bit, when needed, and they don't split or tear open the ends of the rails when you have to remove or adjust them.
The metal was relatively soft, and the track rails crimped right down on them with a crimping tool.
The cars glide smoothly over the pins and joints, including the exposed sections of the pins, the pins never rust, and they seem to conduct electricity just fine. I have had zero derailments. I am not sure what type of metal the rod is made of, but I now keep a six- inch section of this rod in my supply box, just in case I need it in the future.
Hope this may help some folks in the future.
Mannyrock