Friday, April 12, 2013

Hi Gang.

Well it has been too long, so now I need to get much more active both on the kit and on here, so here goes. 
Firstly there are a couple of things about the kit that needs to be said.  The kit will come DCC ready, Sound ready, and have it's own speaker box, fitted in the bunker with a speaker suggestion for the modeller. The smoke box door will open and close (lock) The kit will not be released with auto couplers, it will only have hooks that will take 3 link couplers, and so you will need to have a match truck, one of your choosing. Or modify the kit to suit your favorite auto coupler.

I am still working on trying to make the kit as easy to build as possible, and to this end the instructions will be on CD, and on the net on my web page, so that prospective purchasers will be able to download the instructions before purchase, the CD will also include hundreds of photos of 2029 as it is preserved at The NSWRTM.

So lets have a look at a preliminary view of the frame. (small modifications still to be done)
Z20 Frame with Roller Gauges and Out riggers.

The frame will be etched  0.5 mm half  hard brass with all bracing being of similar material. The red rollers (in above photo, will be supplied and tapped to 2 mm and machined at 26.5 mm. By screwing the frames together and setting the frame up nice and true, the bracing can be placed in position (soldered), whilst the frame is on a level surface, such as glass. Once the frame is set and square the rollers can be removed, as the holes that they occupy will be required to hold other components.

The kit does not have horn blocks and as you can see the etched frame has holes for the bearings, with the front 2 axles having a 0.5 mm  (each way) of movement. The rear axle will be mounted fixed on the frame, with the other 2 axles being allowed to move vertically  There will be internal compensating plates and a compensating cross bar, which I will discuss later.

One of the big problems with the Z20 class is that the footplate has minimal support, with no external stiffeners, so the Outriggers need to support the footplate which is a thin (0.3 mm) etch. These outriggers are also formed from 0.5 mm etched brass and will fold up to attach to the frame using 1 mm screws being tapped into the frame, these can then either be soldered, glued or lock tightened. The outriggers can then support the foot plate, which in turn can support the front sand box and splash guards, as well as being secured to the water tanks, both side and rear and  the bunker. The rear and front steps will be a casting as well, with the rear steps having the water tank balancing pipe as a component.
Castings of the New Buffer Pots and Heads with  Coupler Hooks.

The coupler hooks will be brass castings as will the buffer plates, which will hold brand new buffer pots.
The rear buffer has the air tanks directly behind it, and therefore the old style of buffer can not be accommodated as the shaft would interfere with the air tanks, so I had to either remove material from the tanks or design a new buffer pot, I chose the later.

The way that they work is very simple the buffer pot is designed to accommodate the buffer head shaft which is square with a slot in it. The spigot at the end of the shaft housed a small spring in the tail of the pot . An 0.8 mm pin is then located into the bottom of the pot (not seen) which allows the head and shaft to spring, and also restricts the buffer pots from protruding past the buffer plate. These will be brass castings, and robust. They will also be sold separately when produced.

More information in the next installment.  in a day or so.


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  2. Any updates it's been a few years now ??
    Also your BMT I put off producing one as you said you were doing it and that was a few years ago also any updates on that you had parts on a well known printing site and John said at the last forum in March that you would provide an update in April and it was imminent release ??
    Any news would be better than nothing.