Brio - Mechanical Switch - Signals by cgillstrap

Last crawled date: 3 years ago

This is an accessory/add-on to the Mechanical (Geared) Interchange/Switches that I designed earlier:
Brio - Mechanical (Geared) Interchange/Switch O1/P1 Trackhttps://www.thingiverse.com/thing:4813429
Brio - Mechanical (Geared) Interchange/Switch M1 Trackhttps://www.thingiverse.com/thing:4793935
Basically, after attempting the ambitious Signal Lights (https://www.thingiverse.com/thing:4807078) I discovered that these don't work that well if you have a 2 year old in the house that takes after Wreck It Ralph.  I sought to design something that was more simple in assembly and didn't require a reprint of the core track to create.
The design is meant to evoke a dwarf signal such as what one may find here (https://en.wikipedia.org/wiki/Railway_signal#/media/File:CSX_BAILEY-Marc-1-CPL-Dwarf-STOP.jpg).  It is not perfect in that since you are relying on the knob to drive the signal 90 degrees you only have four options.  However if all you are looking for is some for tactile play vs. accuracy, these should be perfect for a little one to enjoy.
This was printed in PolyMax grey PLA for the shroud and ProtoPasta red, green, white & black  HTPLA for the coloured signs.  The knob was printed in PrimaSelect Red PETG.
Assembly Notes
It is taken as given that you have already printed and assembled one of the geared interchanges/switches in advance and that you are looking to add this on to your assembled print.
In testing and prototyping, I found trying to print the shrouds in wood PLA did not work well.  The brittleness of the material at these tolerances is such that the moment you try to assemble  the shroud it may break and more importantly get stuck in the top recess.  I would recommend against using wood PLA for this print.
1) Print the shroud that corresponds to the track type and orientation you have.  The shrouds are keyed to Right Handed (RH) and Left Handed (LH) turns.  
2) Print the revised Gear Knob which will have the faces for your signs
3) Print the signs.  If you want a multicolour effect, you will need to don a filament change at 0.80mm
4) You will need to glue the signs onto the Gear Knob.  Any commercially available superglue should do the trick.  It is important that you think through how you want to glue the signs onto the knob.  Think through what the signal will look like with the track going straight vs going into a turn.  It may help to write this out on paper before you glue.  
5) If you are adding this on to an already assembled track, you will need to knock out the existing knob from the 20mm diameter gear.  I found a tiny screwdriver and a light tap from a hammer or mallet does the trick
6) Assemble the shroud onto the track paying attention to how the walls extend down to the track base.  Have a look at schematics on the print for guidance.  
7) Ensure the shroud ring is firmly seated into the grooves for the track before assembling the gear knob
8) Slot in the gear knob, paying attention to the aspect(direction) of the switch, you will want to make sure that the signs align to the direction the track is in before the knob is assembled into the 20mm gear at the base.
Hopefully, you should be good to go.