So I've done a bit more work on the point control in that it will now actually throw an OO9 gauge point. This is achieved by attaching the servo arm to the point tie bar using some 0.5mm diameter piano wire running through some 2mm diameter aluminium tubing (both from Albion Alloys) to keep it in place; i.e. a proper wire-in-tube system.
Everything is currently just held down with double sided tape but that seems to hold well enough for experimentation. I could have glued the point down though as I won't be using it on the layout having damaged it beyond repair when soldering on the wires (one of the sleepers is so buckled that the switch rails don't line up so things derail) but it works for this purpose. I found using the second hole from the end of the servo arm and a rotation of 10 degrees was enough to nicely throw the point. The calibration was a bit hit and miss though so I need to work on the software on the Arduino to make that a bit more user friendly but so far I'm happy with how it is all working. If I can figure out how, I might slow down the action to be a bit more prototypical, although that might be tricky given that I'm still relying on the spring in the points to help complete the throw.
Next up will be checking that I've understood the frog switching wiring correctly by attaching the three wires from the point to the relay and checking for the expected power flow through the point.
So I've done a bit more work on the point control in that it will now actually throw an OO9 gauge point. This is achieved by attaching the servo arm to the point tie bar using some 0.5mm diameter piano wire running through some 2mm diameter aluminium tubing (both from 
Mark, what is wrong with plastic tube? Recycle empty Biros or earwaxed cotton bud tubes. Just thought I'd ask.
ReplyDeleteThat's a good question. Technical there isn't anything wrong with the idea and I like the recycling idea. In fact plastic might be better as it would allow for the slight curving of the tube. I went with aluminium as it was what I could buy in my local model shop, and in theory I could do a much longer distance than I could with an old biro or cotton wool bud tube. Having said that I'll certainly remember the option for the future.
DeleteThis is all fairy magic. Seriously though, I am very impressed, I could never begin to do something like this.
ReplyDeleteI could just have bought something off the shelf to do this, but thought it would be more fun to try and figure it out myself. No guarantee it will be any cheaper or easier though. I do have some ideas for turning this into a simple solution for others to use as well. I guess with background in computing I at least have a rough idea of how to achieve what I want.
DeleteHaving said that, I still think the way your buildings turn out must involve a hefty sprinkling of fairy dust as I just can't imagine creating anything anywhere near as good.
I suppose this at least partially explains why a lot of people join a group to build layouts so that people with different skills can contribute and the final result looks good and works electrically. I'm much more of a go it alone person though but at least that way however the layout turns out I know it will all represent my hard work.