OO9 couplings - type 1.

Recently I decided that making my own loco buffer/couplings might be a nice little project, and a good way of personalising a model. So as a start I've machined up some couplings for my Saltford Models Audley. I have a few different coupler variations in mind, so I'm calling these my type 1 for future reference. (The main reason behind this blog is to record my work for my own use.)

The first job was to make a fag packet sketch (quite difficult when you don't smoke!), then from that a prototype which I wasn't overly happy with. So after a quick revision I set to work.

The first job was to mount a length of 6mm bar in a machine vice on my Unimat SL and drill a .6mm cross hole about 2mm from one end;

To position the drill in the middle of the bar I made a mark on one side with a permament marker pen. Then the drill was lowered and moved across until it just touched the bar and left a witness mark (which can be seen in the photo above). Then with the drill raised up again the vice was moved over by half the diameter of the bar plus half the diameter of the drill (3mm + .3mm = 3.3mm). This positioned the drill exactly on the centreline of the bar, and a hole could then be drilled through.

Now the bar could be transferred to my Unimat 3 and the basic shape turned;

The head is 5mm dia. x .9mm long, the shaft dia. 2mm dia. x 2.2mm long and the coller 3mm dia. x .6mm long. There's also a 2mm dia. stub to fit into a hole drilled in the loco's bufferbeam. I carefully machined the shaft with a grooving tool making sure that the .6mm hole sits directly behind the head, machining the head to length after all the basic turning is done. Finally the head is rounded off with a file and emery paper,

At this stage its not unlike a normal buffer.

Back onto the SL next, set up in the vice with the .6mm hole set vertical, done by placing a drill into the hole and checking with a square. Then 1mm is milled from the top of the head,

The final machining operation was to part the coupling off in the U3. Then the end of a length of .6mm brass wire could be tinned and soldered into the hole, being trimmed to length afterwards with 2mm sticking up;

I machined up 3, just in case I made a mistake!

Now, normal OO9 coupling height is set at 6mm above rail level. The centreline of these sits at 4.5mm above the rail top, so I machined up a 4.5mm thick gauge so that I could mark the bufferbeam for drilling;

Here's one coupling in place, after drilling a 2mm hole in the bufferbeam;

It suits the loco, sits at exactly the right height and should work rather well. Quite a satisfying little job.

Remember that clicking on a photo brings up a larger image.

Paul.