Very Compact Servo Turnout Mechanism Design

[justin1985]

Japanese YouTube user "diorama111" has got an awful lot of attention recently with his IR controlled motorised 1:150 Toyota Crown model (I enjoyed the fact he used a 'fonly lathe to turn down the original wheels to take tyres ...) but I took a look through the rest of his channel, and there are some really ingenious mechanisms and designs for miniature models in all kinds of scales and varieties. 

 

His "Slow motion turnout machine 2" really caught my eye - his design is a micro-servo moving a very simple under-track tie bar, controlled by a AT-Tiny chip (smallest flavour of the micro controller series that is the "brains" of an Arduino). Beautifully, it all fits within the plastic roadbed of a KATO HO gauge turnout. 

 

 

I know there are basically as many designs of Servo mount and other forms of Turnout Operating Mechanism as there are modellers building their own track, but this neat little design - just a very simple ex-center pin rotating in a very simple under-board tie bar - seems wonderfully elegant! It makes it look like we've all been over-engineering our turnout servo mounts, doesn't it? 

 

Justin

[nick_bastable]

very neat  I'm  using a bigger version the  stl is   via MERG  to produce these can be fitted with microswitches    although I use relays  give a  nice slow gentle  Linear action 

 

 

have fitted 9 for the revised home layout which is almost ready to really  play test 

 

Nick B

[TomE]

16 hours ago, justin1985 said:

Japanese YouTube user "diorama111" has got an awful lot of attention recently with his IR controlled motorised 1:150 Toyota Crown model

Just watched that video....

 

 

Tom. 

[justin1985]

The MERG version looks good. I came up with this little design, after a few revisions

 

 

The bar has dimples for holes to be drilled for spacings from 6.5mm up, and the servo horn has a few dimples for drilling and fitting the pin at different distances - this version is 0.75mm, so giving 1.5mm travel on a full 180 degree rotation.

 

It's running from an Arduino - I'll play around with slowing it down in the code. It could also do with a tweak to add a guide to make sure the microswitch (subminiature) arm doesn't push back against the bar too much.