O gauge live steam

Discussion in 'Workbenches, including workshop techniques.' started by jamiepage, 15 October 2018.

  1. jamiepage

    jamiepage Western Thunderer

    I've long been interested in 7mm live steam, and in fine scattergun tradition recently pushed aside a couple of other projects and made a start.

    One of the real experts in the field, Clarry Edwards, described in MRN, Feb 1961, a live steam M&GNR 4-4-0. Full of good tips, the article showed his idea of a separate cylinder/ crank axle unit which could then be fitted within a one piece cosmetic frames/ footplate/ superstructure unit.
    A sort of steampunk RG7 idea really.

    The M&GN 4-4-0 used a single cylinder with 2:1 gearing and I have followed suit.

    First job was a cylinder block, machined up from a nice piece of bronze.

    Rather than a conventional slide valve I took the idea used in the G1MRA ARM1G design with a circular section steamchest and valve. I do not think I've ever had an original design idea, but am very grateful to the true engineers that do come up with these ideas).
    Some careful drilling with 1.2mm steam ports and 2.2mm exhaust way joined the relevant bits up.
    (The slide valve is sitting upside down in this photo)

    Screwed glands for both piston and valve rods were fitted to a one piece back plate. A plain front plate and top plate with angled steam inlet and blastpipe completed the block.

    Two 'mainframes' were cut and drilled, then fitted with bearings for both crankaxle and driving (wheels) axle after which the crankaxle, crank etc could be made up and tried for size.

    Dog Star, Arty, mswjr and 3 others like this.
  2. jamiepage

    jamiepage Western Thunderer

    The crankaxle, complete with gear wheel, was silver soldered together, and a slip eccentric timing collar fitted. Valve eccentric, eccentric rod and strap just about completed the gear.

    Assembly fortunately showed it all fitted.


    The completed assembly.

    This photo taken just before the air line was pushed on for the first time. It runs.
  3. mswjr

    mswjr Active Member

    Glad your back on here posting Jamie, Nice bit of engineering as usual ,And a lot bigger in the pictures as in real life, And youve started another project, Must be a model engineering thing,as ive about 3 on the go at once as well.
  4. jamiepage

    jamiepage Western Thunderer

    Good to hear from you, Garry. Yes, it's yet another project; fun, but I need to remember it's also good to actually finish something occasionally.
    Here it is against a 7mm drawing of a Rhymney P Class 0-6-2T.

    What are you building now?
    Jon Nazareth, JimG, daifly and 4 others like this.
  5. Mike W

    Mike W Western Thunderer

    But ... but, It's not MSWJR?

    Very nice indeed Jamie.
    Jon Nazareth and mswjr like this.
  6. jamiepage

    jamiepage Western Thunderer

    Ahh, but it would fit..

    Jon Nazareth, mswjr, adrian and 5 others like this.
  7. mswjr

    mswjr Active Member

    Nice, both would look nice,Both a lot of work, I am building a Hunslet Linda in 31/2 inch gauge and oo gauge Malvern road cheltenham, and a gauge 1 9f ( this one is hard work) and some wagons started for the Hunslet, And still have ideas in my head, Guess we just like making stuff.
    Jon Nazareth and jamiepage like this.
  8. adrian

    adrian Flying Squad

    I shall be watching with interest as I've always enjoyed the live steamers.

    I was most fortunate to meet Clarry on a number of occasions and closely inspect and watch many of his loco's running. As you say a real expert in the field.
    jamiepage likes this.