2502 Hyperion A3 3.5” gauge

[CF MRC]

This 3.5” gauge A3  was recently offered for sale by the Steam Workshop.

 

 

Consensus from the learned came down to one of the last batch of A3s and of these, I have chosen 2502 ‘Hyperion’ to fit most aspects of the model’s condition; name plates are now on order. It rather elegantly graces a window sill at home. 

 

 

The engine is very well made / engineered and should run well at the NLSME tracks at Colney Heath (as soon as life becomes more normal).  However, it has quite a lot of features that can be improved, especially around the cab area. This is about 4mm too tall, originally because the manifold and fittings were too high. It’s also a bit wide and the firebox a bit narrow, but that may be trickier to modify. The manifold has now been lowered and so some surgery will be made to the bottom of the cab, amongst other things.  There will be many other area where I think the engine can be improved and detailed: it is a bit plain. 

 

 

Should provide a bit of distraction in these strange times: some show track and a rolling road is a priority.

Tim

Edited March 29, 2020 by CF MRC

[t-b-g]

I think you may need to put the one from Copenhagen Fields on the footplate and photograph the two together.

 

"If I eat all my coal, one day I may grow up into this".

 

She looks lovely Tim.

[greenglade]

Hi Tim

 

Great to see you posting plans/progress on your A3 here, I shall be following it with great interest... hopefully when things return to normal I'll get to see her at the NLSME track....have fun...

 

Pete

[CF MRC]

I’ve spent the last few days making some display track for Hyperion.  Supplied by the Miniature Railway Supply Co. the concept is very good, but quite labour intensive. 

Quite interesting applying model railway weathering techniques at such a large scale. 
 

Tim

[CF MRC]

Papyrus now looks the part on some proper track.

 

For comparison, we have Papyrus from Copenhagen Fields on the running plate.

 

The dome on the model is incorrect for Papyrus, indeed any pre-war A3,  as it is of the streamlined type. 

 

As this engine is going to become Hyperion, I sourced a pre-war, proper banjo dome casting from Blackgates. 

 

Inside this lump of gunmetal was the correct shape trying to get out.

 

A little BLack and Decker 1/2” belt sander proved to be useful for fettling the casting, which has some interesting geometry interacting with the cone of the boiler.  Making it fit was tricky as I didn’t want to cause more damage to the paint than was necessary - it will be touched-in for the time being.  I really much prefer the appearance of this dome, I think it has an elegance about it.

 

Tim

Edited April 4, 2020 by CF MRC

[CF MRC]

The dome has now been painted (only brush finished) and fitted.  The engine will eventually be completely re-sprayed when I have finished modifications to it and so I’ll be able to improve the fit at that time.  

I made up the rolling road yesterday (from the Model Engineers Laser).  A very substantial piece of kit.  The engine was lined up on it in the kitchen as that is closest to where it lives at the moment.  I will have to get a lifting  trolley to shift her as her weight is not trivial. 

I now need to make some bits and pieces to enable her to steam - shovel, poker, blower chimney adaptor etc. 
 

Tim

[CF MRC]

I had the A3 in steam today on a rolling road for two hours.  Quite a learning curve keeping a small engine in steam. She runs well and I’m beginning to work out what sort of fire works best.  There is are a few areas need investigation for slack and wear, but one step at a time. 

https://youtu.be/DF2R_LoT_to

 

Tim

[garethashenden]

What is the fuel?

[CF MRC]

Coal

 

Tim

[t-b-g]

I think the loco inspectors will be very happy with the lack of wobble at high speed. Just like a full sized A3!

[CF MRC]

I’ve been doing a lot of work on the cab and firebox these last few days, so she is really beginning to look like a proper A3. 
 

Tim

[CF MRC]

The cab on the A3 has been lowered by 3/16” and the firebox widened by the same amount on each side.  I think she now sits like an A3 at the back, especially when compared with the original condition which was much too lofty and skinny on the firebox. 

 

Holes have been made for the missing washout plugs and mud hole doors at the bottom of the boiler.  The ash pan should have some large brackets on either side of it, front and middle.  The roof ventilator will be replaced by a more accurate representation at half the height and the rain strips moved to the correct position.  Further detailing at the cab end e.g. spectacle windows, will wait until this is stripped to bare metal for repainting and numbering.   A lot of lining out is to be reinstated as a temporary trial of techniques before that. 

 

She fits the work bench well and also has the advantage of being easily lifted, turned over and generally manoeuvred for working on.  Quite nice to be able to work on something with just reading glasses. 

 

Tim
 

[CF MRC]

The lining out around the cab and firebox on the A3 has progressed quite quickly using an ‘easi-LINER’ pen. These are tube capillary flow-type pens that take un-thinned gloss enamel paints. In sizes 0.25, 0.5, 0.75 and 1.00 mm they are easily fine enough for a 3/4” scale model.  They work well in this size and are much quicker and more versatile to use than a bow pen over the distances to be covered.  
 

The washout plugs were first lined out freehand in white: these can be quite thick lines as the black will be use to reduce the line thickness. In fact, of course, the white lines are grey as this produces a much less prominent line. 

 

The pen was used to follow suitable edges to back fill the black lines and the set can use an edge follower where appropriate.

 

The extra lining has really made the back of the engine much busier. The finish is OK, but is hampered by the relatively rough paint work beneath, especially where I have made the modifications to the body work.  On final assembly, I will make some adjustments to the line weight and evenness.   I will probably also make greater use of templates when I do the definitive re-paint.  

 

The last remaining lining will be the boiler band immediately in front of the cab.  This will actually be made as two separate pieces, joined with a nut and bolt at the top: you can’t do that in 2mm scale!

 

Tim

 

Edited April 18, 2020 by CF MRC

[CF MRC]

The last boiler band was made from 8 thou brass strip, painted with Plastikote gloss black. This is actually a good heat resistant paint but also flexible.  A 12BA clearance hole was drilled at one end and it was then both taped down and a 0.5mm line drawn on one side.  

Once the paint was hardened the end with the hole was bent at 90 degrees and the other end formed into a hook to engage with the firebox cleading at the  bottom.

 

At the top, the 12BA nut and bolt tightened the band onto the firebox - 12BA is the biggest screw size I use in 2mm scale...

 

The end result looks a lot tidier. 

 

The engine and tender line up correctly now, do you think it looks more like an A3 now?

 

Tim

 

[greenglade]

Looks very much like an A3 to me Tim... nice work.

 

Pete

[CF MRC]

Not much to show for it, but the front bogie wheels have been re-painted and lined on the A3.  The driving wheel rims also need re-painting to be more accurate.  There is a very attractive evening light that bounces off the far side glass in the room to light up the valve gear.

Tim