In line with my recent work on brass signals (last post) I have redesigned the Werris Creek platform starter bracket signal and had it printed in brass. This 3D printed signal was received a couple of weeks ago, prior to my last post.
Here are a few photos of the model as it stands today.
I have painted one signal dolly post for the photos in this blog post but I will be stripping the paint off and spraying the whole signal with some self etch black which will prime the brass and be suitable for the black parts. Of course painting white over the black will be interesting as it will have to be done by brush, carefully.
The prototype signal does not have bellcranks to transmit the signal box lever movement via wire to the signal arm and uses wheels instead. I designed the signal to have working wheels (drilled with holes to be a bellcrank) to get the operating rods up to the signal arms however they are just too small and fiddly to fit. In future the wheels will be cast in place (non-turning) and the operating rods will be bent to run behind the wheels.
To get the operating rod movement I used one piece of 0.015: phosphor bronze wire from the below baseboard mechanism to the counterweight lever. I bent it to replicate the operating wire of the real signal and threaded it through the wheel brackets behind the wheels. Check the photos to see what I mean. A loop of 0.010" wire was bent into a U shape and soldered to the post to retain the two operating rods and minimise flexing of the wire.
The brass post is glued to a boss on the top of the White Strong and Flexible, the square base of the post being hollow.
The two round steel dolly posts are 1mm diameter brass tube from Albion Alloys which can be purchased from Hobbyco, Bergs Hobbies, Brunel Hobbies and Frontline Hobbies. The detail parts on the dolly posts are Frosted Ultra Detail parts that slide onto the posts. The dolly posts fit into holes printed in the signal that need to be cleaned out with a 1mm drill.
Some holes need to be drilled with a 0.4mm drill, some cast OK and some don't. A supply of 0.4mm drills would be useful as I find that some drill well and others don't. I think it is how well the point has been ground.
The drills can be found on ebay or a pack of 10 drills can be had for $10 from McJing Tools in Yagoona NSW.
I will be investigating how to do these dolly posts with details attached in printed brass. I have to keep the height below the 100mm maximum build box of the 3D printer, so some more 'hidden' sprues.
This signal is a trial for the steel post bracket signals to go with the round steel post signal now available on my Signals Branch Shop.
Once this signal is done I will return to the Werris Creek station building, at last - again!
If anyone is interested in how my signals go together I will be having a clinic at the Modelling the Railways of NSW Convention at Loftus on 20 May 2017.