Princess of Wales horn stays

[Bruce BoldnerParticipant @bruceboldner96125]

Hello all,

I have just discovered and joined this forum.

I am building the Martin Evans 5" inch gauge live steam 4-2-2 locomotive the Princess of Wales and have all but completed my rolling chassis.

However I am having difficulty determining the shape of what I presume to be the horn stays on the main driving axle boxes on the outside frames.

The Evans plans depict these as simple mild steel rectangles bolted across the bottom of the horn blocks.

However, all photos I have of the Midland spinners show what look to be inner and outer horizontal tubes placed across the bottom of the horn blocks. These tubes also appear to have a hexagonal nut or bolt head at either end.

Unfortunately none of these photos are large or clear enough to determine the exact shape and nature of these fittings.

A visit to the preserved no.673 at the NRM might help. But I live in Australia, so this is impossible. In any case photos on the NRM website show that there is now a tightly fitting platform around both sides of the engine, which blank off the view below the bottom half of the brass covers over the axle boxes.

This therefore to ask if any members can shed some light on the nature of these items for me.

Are the tubular constructions part of the horn stay? If so, is there a flat plate between the two directly beneath the axle box, through which the vertical rods holding the springs may move up and down, at the same time trapping the coil springs from moving upwards?

After trawling through 455 pages of drawing lists on the NRM website, I have discovered just one drawing headed Paris Exhibition Engine – Princess of Wales.I have emailed the NRM to ask if a copy may be purchased. However, I doubt this is a general arrangement drawing which would show the detail I require.

If any member of this forum might have a clear closeup photograph of this hornstay which could be posted online, or even a detailed description, it would be invaluable and much appreciated.

All the spinners appear to have had this same horn stay(if that is what it is), even the first versions which had leaf rather than coil springs.

Thank you in advance for any assistance anyone can give me.

yours sincerely,

Bruce Boldner.

[Bruce BoldnerParticipant @bruceboldner96125]

[julian atkinsParticipant @julianatkins58923]

hi bruce,

i am not a Midland Railway fan or expert, but the tubular form of hornstay is not uncommon. i fitted them to 2 of my locos. very careful fitting is required. i cant comment on the spring arrangement im afraid as mine have leaf springs above.

cheers,

julian

[Bruce BoldnerParticipant @bruceboldner96125]

Hello Julian,

Thanks for your response to my question. Could you possibly post a photo of one of your tubular horn stays ?

Or perhaps give a more detailed description of how they function? I cannot understand why there would be bolts tightening laterally across the bottoms of the hornblocks, when all that should be required is a simple stay bolted to the bottom of the frames to prevent the axle box falling out of the frame.

It has been suggested to me that these lateral bolts would be tightened to draw the hornblocks more tightly onto the axle boxes when the hornblocks wore down a bit.

Yet another person reckons this is a ridiculous supposition , saying it would be impossible to pull the frame cutouts together.

To this the first person said that some hornblocks have wedges which can be driven higher to force the hornblocks tighter against the axle boxes as the former wear. The lateral bolts could then be tightened to hold the repositioning of the hornblocks.

i really don't know what to believe.

i do know that I have no wish to fabricate the horn stays according to how I might imagine them to be, only to discover later that that are totally wrong.

regards,

Bruce.

[julian atkinsParticipant @julianatkins58923]

hi bruce,

the 'tubular' hornstays must be made a dead fit to the final width of the horncheecks after checking the final fit of the axleboxes etc.

hornstays are exactly what it says on the tin ie to prevent the bottom of the horns moving. i dont think in fullsize the MR used wedges which in any event is irrelevant in our scale.

cheers,

julian

Edited By julian atkins on 19/06/2014 00:37:49

[Bruce BoldnerParticipant @bruceboldner96125]

Ok. Thanks Julian.

regards,

Bruce.

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