Hinged switch blades - any ideas, please?

Discussion in 'Permanent Way' started by jonte, 22 March 2020.

  1. jonte

    jonte Western Thunderer

    Dear fellow Westerners

    Has anybody any experience of this and possibly any examples/ideas they’d like to share?

    I’ve had a quick look through the other threads in this section and also via the usual search engines and thus far nothing has come to light. Apart from Peco’s method of hinging the blades in their ranges, the only other mention I can recall, is that of Gordon Gravett employing it for his fabrications on his latest quayside layout. I think I read this in the article when it appeared in MRJ, but don’t recall him going into any depth about it.

    My own initial thoughts involve possibly drilling the base of the moving rail (4mm scale) and soldering in a pin of some sort - and allowed to swivel in a brass tube of an appropriate bore perhaps - that slots through say a brass plate soldered to the base of the adjoining fixed section of switch rail, retained by a small washer soldered on crank pin style on a locomotive (if that makes sense?).

    I’m aware that their are other ways of doing all this that remove some of the strain on the soldered joints of traditionally hand-built track work, but I’d be interested in exploring this anyway, hopefully with some good ideas from my friends on here with more of an engineering bent.

    Prototypically, I recall someone once writing that this type of hinged rail was employed by the GWR in its earliest days; there were certainly plenty of examples in the miles of inlaid track of Liverpool’s docklands, in my own experience.

    I look forward to receiving your thoughts on this.

    Jonte
     
  2. simond

    simond Western Thunderer

    Jonte,

    I typically solder a “fishplate” made from phos bronze strip into the web on the inner side of the blades, provides flexibility & alignment, supports the blade and gives electrical continuity.

    Slaters sell it, it fits passably well in the web of 7mm rail, not sure where you’d get something suitable for 4mm, perhaps you could cut it down with scissors.

    hope it may lead you to a solution
    Atb
    Simon
     
    jonte likes this.
  3. victorianman

    victorianman Western Thunderer

    I've done it in S and S7 by using the cast brass fishplates sold by C&L. If you have a reasonably flexible operating method for the switches, there may be no need to solder anything; the spring effect from a sub-baseboard operating wire (as with a Tortoise, for example) can be adjusted to push the 'tie bar' and thus the switches towards the swivelling joint, keeping all in place.
    I think most pre-WW! companies would have this type of so called 'loose heel' switch, but the sprung blades with which we are more familiar also started to appear at that time, so to be completely authentic it is necessary to check photos of the period one models.
    Hope that helps.
     
    jonte likes this.
  4. victorianman

    victorianman Western Thunderer

    PS. Forgot to say on the railway I model, the end of each switch and closure rail rest on some kind of support on a sleeper, so nothing is in mid-air and the joint is supported. This can be reproduced by a track rivet serving as the support. Again, not all companies did this, so check photos.
     
    jonte likes this.
  5. jonte

    jonte Western Thunderer

    Many thanks, Simon, for your usual prompt and constructive reply :)

    Your suggestion has crossed my mind, but more as complimentary to the pin option as mentioned. It’s still helpful as at least I now know of an option that works AND where to get hold of it.

    Many thanks once again.

    Jonte
     
  6. jonte

    jonte Western Thunderer

    Good morning, victorianman, and many thanks for sharing.

    It would appear that the C&L method you kindly suggest is along the lines of Simon’s phosphor bronze strip mentioned in his earlier post, and seems to be a worthy option.

    A non-soldered and thus flexible method of switching as stated would indeed seem an ideal solution, although I’m just a little concerned about ‘protruding’ blade ends above the stock rails becoming an issue.

    This is not a criticism of your knowledgeable suggestion btw, just a distinct lack of it on my part :(

    Still, it looks as though there is a chance of this working after all!

    Thanks also for the heads-up on the prototype - I shall dig out Mr. Williams’ tomes for starters ;)

    Best wishes,

    Jonte
     
  7. Mike Trice

    Mike Trice Western Thunderer

    A long time ago I had a go at building some N Gauge turnouts based on Swiss practice. These were built with hand cut copperclad and code 55 n/s rail:
    IMG_1614.JPG
    In order to function I really had to implement hinged switches. The basis is the old trick of using a fishplate to provide the hinge and keep the rail aligned, however a length of fine flexible wire was soldered across the joint to maintain electrical continuity:
    IMG_1500.JPG
    In order to maintain flexibility I also had to use pivoted tiebars. Two staples were bent from n/s wire and the arm trimmed short (I think the Peco track pin was for comparison):
    IMG_1617.JPG
    Tiebars were a piece of upside down pcb with the holes countersunk underneath. The countersinking means the tiebar tails rebate and don't get in the way and it also provides electrical insulation. The longer tails of the uprights are bent through 90 degrees:
    IMG_1620.JPG

    Finally the long tails are soldered to the side of the rail with a piece of paper below to stop soldering to the sleeper.:
    IMG_1622.JPG
    It should be possible to make it far less visible in 7mm.

    Hope it helps.

    P.S. I openly copied Tim Warris
     
    Last edited: 22 March 2020
    Alan, jonte, chrisb and 1 other person like this.
  8. Obblygobbly

    Obblygobbly Active Member

    For 4mm scale, Peco's new bullhead rail joiners work very well in my limited experience. They look the part as well.
     
    jonte likes this.
  9. jonte

    jonte Western Thunderer

    Hi Mike, and a sincere thanks for your time and trouble.

    It looks like the ‘hinged’ fish plate is a recurring theme here and I like the belt n braces approach with the fine twisted wire.

    Thanks also for adding info about the flexible tie bar; a neat solution and one which appears ‘do-able’ ;)

    I recall Iain Rice building a flexible tie bar of sorts in his track making book, but the thought of rising switch blades always crossed my mind, although I could be doing him a great injustice.

    Thanks for posting Tim’s vid. I’m quite familiar with his work from my American HO interest.

    Thanks for sharing,

    Jonte
     
  10. jonte

    jonte Western Thunderer

    Another nod to the fish-plate here, Obbly :)

    I’ve got several of those and you’re right: they look the part indeed.

    Many thanks for your suggestion.

    Jonte
     
  11. Obblygobbly

    Obblygobbly Active Member

    The Peco bullhead rail joiners are relatively hard and springy - ideal for this application. I have found no need so far to solder them in place.
     
    jonte likes this.
  12. chrisb

    chrisb Western Thunderer

    This might also give you some ideas:

    MRJ no.113 p.220 Straight-cut point blades

    J.R. Snowdon describes construction of point blades with the prototypical kink in the stock rail at the hinge between the switch blade and the closure rail
     
    jonte likes this.
  13. victorianman

    victorianman Western Thunderer

    Re the possibility of switch blades rising above the stock rail at their tips, this won't happen if you can have a tie bar that is rigid at the point where it is attached to the switch blades and is also made to extend outwards beneath both stock rails. Alternatively, a piece of stiff wire can be soldered beneath the switch a little way away from the tiebar and made to extend beneath the stock rail. This will stop the blade rising and might also give some electrical continuity between the two. I have personally adopted the system outlined in the Trax 2 book, which uses small pieces of gapped pcb beneath each switch/stockrail, tied together by wire, shorts prevented by the gaps.
     
    jonte likes this.
  14. jonte

    jonte Western Thunderer

    Thanks, chrisb- i’ll Pop into the loft to see if I’ve got this edition.

    Jonte
     
  15. jonte

    jonte Western Thunderer

    Thank you once again, victorianman, that makes sense.

    Jonte
     
  16. jonte

    jonte Western Thunderer

    Just a line to record my further gratitude to Mike Trice for some additional info re my query.

    Thanks, Mike!

    Jonte
     
  17. jonte

    jonte Western Thunderer

    Just as a footnote to my post, and for the info of fellow Westerners who expressed an interest, I decided to dig out my copy of MRJ No. 258 which contained the article on Arun Quay, to check whether my failing memory had served me right when I mentioned a couple of posts back that the creator, Gordon Gravett, hadn’t gone into detail about how he fabricated the hinged switch blades on his 7mm scale turnouts.

    And, unfortunately, indeed it had, there being no mention of what method(s) had been employed.

    However, by sheer coincidence, an accompanying article by a chap named Peter Johnson, not only made mention of the hinged switch blades employed on his Birkenhead Docklands themed layout, but also went into some detail as to how they were formed and made to work. Bingo!

    Interestingly, it was along the lines of my humble cogitations, he employing a stub of soldered pcb sleeper instead of the brass washer fixed con-rod style as I’d contemplated. Brass wire affixed to the underneath of the thin ends of the blades slotted into long thin pcb sleepers beneath the baseboard, to act as actuating rods in much the same style advocated by Ian Rice. A detailed photo of the homemade TOU operated by a solenoid accompanied the article.

    I’d like to attach a copy of the article for my friends here, but I rather suspect copyright precludes this.

    Anyway, glad I found it and happy that this sort of system not only exists but works satisfactorily too.

    Thanks all once again for your kind assistance.

    Jonte
     
  18. Mike Trice

    Mike Trice Western Thunderer

    Interesting. I look forward to how you get on.
     
    jonte likes this.
  19. Les Golledge

    Les Golledge Active Member

    Hi Jonte,

    Try this thread on Templot, the first post shows pivoted switchblades using small brass bolts.
    Hope this is of help to you & anyone else who needs pivoted switchblades.
    Regards,

    Les.
     
    jonte likes this.
  20. Les Golledge

    Les Golledge Active Member

    Mike Trice and jonte like this.