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 Post subject: Outriggers
PostPosted: 31 May 2014, 20:33 
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Newly Regd User

Joined: 31 May 2014, 20:20
Posts: 2
Could anyone tell me how the outriggers on R&R 45 ton ADRR95212 work? Are they pulled out by hand, gears,steam or hydraulic? Sorry I'm new to rail cranes but find them fascinating. Thank you.


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 Post subject: Re: Outriggers
PostPosted: 01 Jun 2014, 00:38 
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BDCA Member

Joined: 16 Apr 2013, 00:38
Posts: 51
Location: Poole, Dorset
They are manually moved in and out by gears operated by a ratchet. One for each Beam.


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 Post subject: Re: Outriggers
PostPosted: 01 Jun 2014, 09:08 
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Joined: 15 Dec 2010, 22:30
Posts: 270
Location: North Cambridgeshire, UK
We tend not to use the term "outrigger" for this extending type of support, it being more applicable to the hinged swing-out type. Note that 'beam' is one of a number of alternative names which include 'propping girders', 'girders' or simply 'props'. I normally use the latter term but will stay with 'beam' for this reply.

The beam-extending rack on an earlier R&R crane can be seen in this photo (click on it to enlarge): http://www.bdca.org.uk/gallery/index.ph ... ndercoated. The rack on the 45-ton cranes is similar, the main difference being that the ratchet lever for extending it is captive rather than being a loose item carried in the crane's toolbox.

The beam runs on rollers as it is being extended, so as to reduce the required effort. As the screw jack (or 'prop screw'!) at the outer end of the beam is wound down, the beam lifts off the rollers and presses against the top of the box. The inner end of the beam will, of course, be putting a downward force into the box.

p.s. It will be obvious from the photo that the crane was being spray-painted. I sprayed two coats each of primer, undercoat and top coat but, to keep the purists happy, I brush-painted the final top coat. ;)


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 Post subject: Re: Outriggers
PostPosted: 01 Jun 2014, 15:45 
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Joined: 31 May 2014, 20:20
Posts: 2
Thanks a lot guys thats a great help. But it leads me to more questions.
1. are the beams even on both sides or are they off set slightly? From the last pic it looks like nearest beam is closer to one end.
2. Are there 6 beams in total.
I'm asking these questions as I plan to make a working 00 gauge model. Thanks again


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 Post subject: Re: Outriggers
PostPosted: 01 Jun 2014, 19:21 
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Joined: 15 Dec 2010, 22:30
Posts: 270
Location: North Cambridgeshire, UK
Quick answers to your questions:

1. The beams are offset as they are too long to be stabled end-to-end.
2. The 45-tonners have four beams. The earlier 40-ton crane in the photo has six, but that was an LMS foible that gave no benefit at all under most conditions.

Good luck with the modelling, and don't hesitate to come again if you need further advice.


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 Post subject: Re: Outriggers
PostPosted: 02 Jun 2014, 16:04 
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Joined: 23 Dec 2010, 00:07
Posts: 317
Location: Poole, Dorset
Before the advent of the ratchet mechanism the girders were pulled out and pushed in manually. I am not sure offhand which was the first crane to have a ratchet mechanism, but my crane (Ransomes & Rapier, 1908) has no such luxury!

To extend the girders, you attach a rope and pull, very hard indeed. Either you go a strange colour and possibly burst a blood vessel, or the girder comes out. Pull too hard, and it comes right out and you're left with the challenge of lifting about 1/4 ton of steel to put back in its girder box!

To retract them, you must hope that you remember to attach a rope or strop to the inboard end before extending them (then you can use a Pullift or similar to pull them back in). If you forget to do this, you have to lift and push and in my experience it is almost impossible for one person to do this unaided.

The girders are very heavy, and although there is a roller at the outboard end of the bottom of the girder box the friction to be overcome moving them is considerable.

I guess in the days when the crane was built labour was cheap and plentiful!


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