The trolley pole Part 1

I have no intention of making my poles accurate to the prototype. The most important thing is that they work reliably. So long as they look the part from a distance I will be happy.

I needed a standard and decided to use the NMRA standard "S-5 for Traction Power Collection" which can be found at www.nmra.org/standards/sandrp/s-5.html
The S-5 is probably old hat by modern day standards but it is something for me to work to and I will be vary happy if all of this works. S-5 calls for a contact force between 0.3 and 0.5 oz.

Which raises the subject of springs. I almost gave up trying to acquire suitable springs for the trolley poles then I met a fellow railway modeller who had been making his own for some time from single strand stainless steel fishing trace wire. So off to my local fishing tackle shop to acquire a roll of "Mason" brand single strand chrome nickel alloy wire. I bought the smallest wire size available at 0.014" dia.

I decided to wind the wire on a 1 mm diameter former. As I don't own a lathe I figured I could use the drill press instead. The 1mm dia brass former was too flexible so I clamped a block of pine to the table of the drill press and with a 1mm drill I drilled a hole in the wood directly below the chuck. This has provided the support I needed and by hand turning the chuck of the drill press I have managed to wind my first spring. So far so good.

The spring seems to have the right amount of tension in it. Now it just has to be cut into suitable lengths and the loops made at each end. But I need to make the rest of the pole first so I can get the right length for the springs.