No.23 Siphons and Mini Couplings

I do like the rolling stock to be close coupled.  This Blog entry is about close coupling ex GWR Siphons of the Airfix / Mainline / Dapol / Hornby varieties.



I like to keep the rolling stock in as near ‘mint’ condition as possible.  I am against cutting and gluing.  For close coupling rolling stock of Airfix origins my usual procedure is to fit Bachmann Mini Couplings (Long).  This solution is totally reversible should the rolling stock need to be sold on.  It also enables trains to negotiate curves down to Peco Medium Radius.  In the past I have successfully employed this technique for ‘B’ Set coaches and 14xx / autocoach combinations.



The view above compares the original Mainline plug in type couplings with the original Airfix style and the replacement Bachmann Mini Couplings (Long).  The picture also shows how the wings on the Bachmann couplings have to be cut off to allow the coupling to be placed in the ‘plug in’ coupling pocket.


As well as removing the ‘wings’ it is also necessary to open out the post hole.  The couplings are soft nylon and this can easily be achieved, rotating by hand a suitably sized twist drill in the existing hole.  I have been using an elderly imperial drill bit 7/64 which translates into 2.778mm!



Having prepared the replacement Bachmann coupling the original Airfix / Mainline / Dapol / Hornby coupling can be lifted out.  I find a tiny screw driver most useful for prizing off the tiny nylon keeper plate.  The modified Bachmann coupling can then be dropped into the coupling pocket and the keeper plate pushed back in place.



I am happy with the looks of the finished product but does it work?  Unfortunately – not yet.  On reversing the rake of wagons through a set of Peco Medium Radius points the buffers locked and the wagons derailed.  On closer inspection the problems appeared to be related to the Siphon H wagons without corridor connectors.  In contrast the corridor connectors on the Siphon G wagons would rub together and keep the buffers sufficiently apart to prevent them locking.  This suggested a solution.




For my Siphon H wagon in the middle I substituted the slightly longer ‘original’ Airfix couplings.  If you had more Siphon H wagons I guess you would need to treat alternate wagons.  Does it work – yes now it works very well:

  

Comments

Popular posts from this blog

No.123 Chocolate and Cream and BR1s – the Replica Railways Restaurant Buffet

No. 163 Hornby’s new A2/2 and A2/3

No. 166 A tale of two Hornby Super Detail ‘Britannias’, plus a Clan (Postscript)