Saturday 23 October 2010

Extending Axles

One of the very distinctive features of the KMX tamper is the outboard brake discs on the bogies, which are considerably more prominent following its conversion from Metre Gauge to 2 foot. (Or 1 foot 11 and a half to be very correct about it).



This is one of the challenges I chewed over during the two or so years before I actually began making the model and the solution I came up with was these brass top hat-type things.



I figured could glue these onto axle boxes of the plastic Kato Shorty bogies and it might look something like those outboard brakes. Tonight I've been trying out the theory.

And it looks like it works!



Of course, as with any prototype build, there were a few false starts and a wee bit of taking off, bodging and trying again until I got there.

On the first attempt the brass extensions were fouling the front bracket for the tie bar that runs in front of the tamping head.

I tried filing down the bracket as far as it could go but the bogie still only had a few degrees of turn.

Clearly the top-hat thingys would have to be made smaller, but how?

I considered reducing the diameter so they would swing below the obstruction. But that was going to be a little tricky without using a lathe and I thought they might end up looking too small.

So what I did was reduce the length of the shaft in my typically improvised way by placing the top hat upside down on my cutting mat, holding it in the jaws of my tweezers with one had and applying a grinding disc in the mini-drill with the other hand.

Not necessarily elegant but it was effective and that's all that matters, isn't it?

So here's a shot of the first bogie side in position on the model.

No comments:

Post a Comment