Modifying Couplings

[IrishPeter]

I use Accucraft chopper couplings on most of my stock, but due to the hook for buffer chain couplings on top, they are quite high profile. I need to eliminate the hook on some of the couplings to lower the profile so a SG wagon axle will clear when bein rolled on/off a transporter wagon. (Yep, the Calthrop bug has bitten!) I assume this can be achieved by either shortening the existing bolt by removing the hook portion, or by using a new bolt (or one scavenged from the 'B' end of a vehicle.

Peter in AZ

[GTB]

 I assume this can be achieved by either shortening the existing bolt by removing the hook portion, or by using a new bolt

The 'bolt' and hook are a single formed piece of rod, with a thread at the bottom. The washer on the top of the coupler box is usually only held in place by the paint in my experience, so shortening the hook would also require cleaning off the paint and soldering the washer to the top of the rod to retain everything in place.

The hook is threaded M2, like the mounting screws they supply in the bag. I just take the hooks out and replace them with an 8BA x 1/2" bolt and nut, so I can recess them in the end sill. 8BA is a bit bigger than M2, but they fit OK.

8BA hex head bolts and nuts will be as rare as rocking horse droppings where you are, but 2-56 is the US equivalent and should fit. The one I measured was between M2 and 8BA in dia............

If you can't get 2-56 x 1/2" locally, try this mob, who have brass ones in hex head, as well as brass nuts. They also list M2 x 0.4 x 12mm, but not in hex head type.

http://www.microfasteners.com/index.cfm

They also stock the #2 hex head woodscrews that I use for detailing wooden rolling stock.

Graeme