LNWR Jubilee

[753]

Mike Williams and I are cooperating in building a pair of LNWR Jubilees.

I will build the engines and Mike will do the tenders, and supply lots of detail castings. We have had all the material for the frames and rods laser cut, the bogie and tender wheels are the same size and have sourced castings, but as the drivers are rather unique no castings could be found. I decided to cut them on the CNC mill from 6mm thick ali with brass centres and steel tyres.

Mike

[MikeWilliams]

Mike, I meant to ask this before.  That picture is so perfect is it the actual aluminium wheels, or a CAD image?

Mike

[LankyTank]

And....

Are these LNWR Jubilees going to go into production, as kits, bits, RTR......?

[753]

Mike
It is a pic of the actual wheels.

Lanky

We are building just two, one each.

Mike

[753]

Wheel sets for Jubilee's




Tyres where turned from 100mm steel bar and press fitted, centres are brass and fixed with Loctite. Quartering is achieved by cutting a keyway at 90deg in the ends of the axles, and a corresponding keyway on the wheel on the centre line opposite the crankpin hole.
The 1/4in dia axles are really too small for this size of wheel, could do with being minimum 5/16in to give a big enough shoulder to hold the wheel square with the axle's,
But as we are using Slaters motor/gearbox units there was no choice, to my relieve the wheels run quite true.

Mike

[IanT]

Very nicely done Mike - look forward to seeing these engines one day.

Regards,

IanT

[MikeWilliams]

Just in case anyone isn't sure, here's a real Jubilee, complete with 2500 tender which these will also have.

Mike

[753]

Progress on the Jubilee, the laser cut parts are soft soldered to make a ridged permanent frame, over the years I have found this system to work well as once the axle boxes are fettled square to the frame and reamed in situ and the axles run true nothing will change. The axle boxes are sprung from springs under the horn keep as in the prototype, the motor is loosely held in a yoke allowing it to float up and down with the sprung axle.

Mike

[753]

A step forward on the chassis, the bogie is fabricated from 1.5mm steel, the axle boxes where milled from solid with the tie bar flanges soldered on. The cylinders are also made from 1.5mm steel, a back plate with folded top and bottom the ends plates soldered on, then wrapped with brass sheet, the covers are solid.
The connecting rod was laser cut then reduced between the bosses and the flutes cut with a 1/16in woodruff cutter found in a box of old cutters in a junk shop many years ago
The buffer beam is brass overlaid with pressed rivets. The buffers are from excellent castings supplied by Mike Williams.

Mike



10 200 code

[753]

The cylinder drain cocks are rather tricky to make, does anyone know of castings available even in a different scale?

Thanks

Mike

[Nick]

Mike,

I'm not an LNWR expert so I don't know what the drain cocks should look like, but where the bodies are spherical I have adapted handrail knobs. I chuck them using the shank and drill the end for the exhaust pipe, and fit the operating lever through the hole where the handrail would go. Alternatively, if you can create a solid model you could get them 3D printed in brass. I had some fittings done that way recently for one of my O gauge models. Not cheap, but they certainly looked good.

It's coming on very nicely.

Nick

[753]

Thanks Nick for the idea, looking at the drain cocks again I have realized they are bigger than first thought, so I think i can cut them from flat and add round parts, we will see!!

Mike

[753]

Making engine motion is probably the most difficult area of loco construction.

Using the fourth axis on the CNC mill to cut the crosshead and con rod fork end makes life a bit easier. By rotating the work through 90deg all four sides can be cut from the one reference point.

The fork end is silver soldered to the connecting rod, the two parts are held in a jig.

I soldered the cylinder cover, slide bars, and motion bracket to be one module, which bolts to the frame at the back of the motion bracket, and makes painting easier.

Mike

[IanT]

Clever stuff Mike - what CNC set-up (machine & s/w) are you using?

Regards,

IanT

[753]

Ian

My mill is a Syil X3 with fourth axis
I use TurboCad and ArtCam Pro both old versions as I know my around them.
I have  Fusion 360 but drives me up the wall, to complicated!

I don't use CNC in the conventional way, using small dia cutters from 1mm to 6mm you need low feeds, high speeds, and small depth of cuts, as I am in no hurry and saves cutters.

Mike