The Burnbake and Woodyhyde Railway

[clayliner]

The lifting tackle was always going to be tricky and to need some simplification. This was my first attempt:


g11 

which gives the general idea. The blocks are two pieces of Funky Foam glued together. Rather stupidly I thought I could improve on this (!) and had another go; this time I put some card spacers in between the pieces of foam to create more of a groove into which the chain could sit more comfortably:


 


Lying on a flat surface it doesn't look very special as it's only when it is hanging that the desired impression is created. Here (after many deleted expletives) is the finished thing:


 


As I say, I'm sure in real life the lifting gear would be more complicated, but it was tricky enough getting the length of the separate pieces of chain right so that it hung symmetrically, and I think it conveys the general idea okay.


Finally, let's see it in situ, where it belongs, behind the engine shed:


    , on Flickr


Actually it's quite a tight fit - I never bothered to measure the space before I started! - but it looks comfortable enough and will be a useful bit of kit for the railway.


244agd  clayliner


Time now to go and lie down I think...

David.

[MickT]

It looks fine to me David. Impression is sound!

Have a good sojourn in the sun and see you hopefully soon after you return.

I'm substituting for absentees and sicknote submissions in the Thursday Club tomorrow but have just realised that if you aren't going then it will be "sans donuts" :(

Mick

[Jeff Schumaker]

Very nicely done, David.

Jeff S.

[Hugh Norwood]

Just a thought... have you tried model boat suppliers? They have interesting things like blocks and possibly very fine chain. I've got stanchions from such suppliers in the past.

[clayliner]

That's certainly an idea, Hugh, and one that had not crossed my mind, as scratchbuilding is the name of the game if at all possible as far as I'm concerned! I like to see what the possibilities are, and as often as not end up close if not actually beyond my technical capabilities. Maybe one day I'll learn and save myself a lot of hassle!

Thanks for the other comments, guys.

David.

[clayliner]

A footnote to the above:

During the later stages of the gantry project, and despite my difficulty in finding any prototypes to guide me, I had a growing feeling that I might have actually seen one in real life. And indeed I had, on the little 600mm Trem do Barril railway in Portugal (which you can read more about in the thread of that name on the NGRM forum). Here it is:

P1030548 

with loco No.3 strung up for repairs (actually on blocks) amid the foliage.


The arrangement at the top is worth noting:

gantry 2 


The overhead beam is two lengths of light rail (probably the original used on the line) side by side, and a wheel with a central flange running in the gap between them, from which a crude stirrup hangs. The main supports, which are steel tubes, have a channel welded to the top in which the rails rest.

Had I known all this at the outset it would have been a useful pattern to follow. (Maybe someone else would like to try making it?)

David.

[MickT]

Good reference material David, but I don't think I would really want to stand underneath that one!

I think yours is much less rickety and looks fine as it is.

Mick

[clayliner]

A 'minor' PW job but one that has been instructive and got my problem-solving juices going... which means I got to pretend to be a proper engineer (what I should probably have been all my past life) for a few moments.

A point has needed replacing. It was the one out of sight, through the wall, which forms the far side of the triangle. It is operated by wire-in-tube (i.e. cycle cable) and probably suffered from a heavy-handed operator. Because there was little or no slack in the system it was probably only a matter of time before something would give, and one of the blades finally parted company with the rest of the  assembly.

The challenge is to provide a throw which is positive enough to move the blades (and which is helped by the over-centre spring in the point), but which has enough 'give' to avoid dismantling the point. Traditionally I think this was done with an omega loop – a Ω-shaped piece of slightly flexible wire – somewhere in the line. I have to confess I have never actually seen one in the flesh, as far as I can recall – does Peco or someone else sell them?

Instead, I've come up with the following arrangement which I hope will do the job okay:


p2a 


The cable (firmly anchored by a couple of cable ties) comes through the wall at A, and is soldered at B to a length of stiffish-but-bendy wire C which extends to engage with the tie-bar of the point.  This pivots at D where it fits in the slot in the head of a chunky bolt which passes through the baseboard. The only improvement I might make is a piece of firm foam to limit the travel of the operating wire in each direction and prevent further damage.

Not pretty, perhaps, but - being out of sight -at least there was no ballasting involved.

David.

[MickT]

Good grief David! That is an engineering masterclass and a half to achieve a fairly straightforward job!!

However, if it works, it has solved your problem and congratulations on managing to work it all out and solve the problem!

Omega loops - yes they do exist. I think Gem used to or still do market them as part of their wire in tube stuff - they use copper tubing. I imagine that other people who supply wire in tube components also supply them. You can fairly easily make them yourself if you use piano wire for the "wire in" part of the wire in tube by using some narrow nose pliers to bend a zig zag shape which works the same way as an omega loop - it absorbs the excessive amount of the "throw" and sort of dampens it down so it moves the point tiebar but without excessive force. Chris Ford has recently posted a photo of one of these zig zags on his own blog.

An alternative method, which I learned from our own "master craftsman" Ian Turner, is to use slide switches to operate the wire and solder small collars of tubing onto the wire where the throw of the point operates, so that the tubing slides freely through the hole in the slide switch that you have drilled and threaded the wire through, until it reaches one of the collars which stops the free movement and therefore moves the wire to throw the point. Easier to show in pictures than try to explain, so here are pictures of the operation!







Hope this explains what I was trying to describe and may be useful for the next occasion as it certainly looks a lot easier than the solution you came up with!!

Mick

[clayliner]

But not as much fun! It actually isn't at all complicated...

I probably need to investigate slide switches some day, and the collars - I'd probably use the brass connectors from electrical connector blocks on my bicycle spoke actuators - are a good idea.

David.

[MickT]

Ah, bicycle spokes! Ted Polet perfected a system some years ago when he rebuilt Rae Bridge on his Craigcorrie & Dunalistair Railway which uses bicycle spokes at the operating end, so the operator pulls or pushes the end of the spoke which is mounted at the baseboard edge. Meanwhile under the board, the other end of the spoke connects to a choc box which in turn is connected to a wire in tube arrangement that then goes off on a journey under the baseboard until it reaches the vicinity of the point (or signal) that it is set to operate. Then via an ingenious arrangement of the blades of standard wooden clothes pegs, with brass strip glued to the ends, a lever operated microswitch is actuated which controls the frog polarity and the point blade is thrown in the right direction.

It sounds horrendous but it works, I think Ted may have described this system on his Dutch Group website either under "projects" or via the link to the C&DR separate website. I even made one of these constructions myself one balmy saturday afternoon about 20 years ago and rigged it all up on a sundeala test track, and even I managed to get it to work which, considering the rather complicated system, was very satisfying indeed. Fortunately for my sanity however, Ian Turner's slide switch method was much simpler and covered both the operation of the point and the polarity in one simple movement so I went off in that direction for my first (now very much abandoned to historical archive) layout effort!

Mick

[B.Meldon]

We use a simple 'Z' bend or omega loop in the point control wires to limit the forces on the point blades.
We also drill a hole through the plastic on the operating switch for the control wire.

[clayliner]

Yes, I know Ted is a fan of bicycle spokes, too. Fortunately all my points are directly within reach of a spoke - except this one, hence the cable.

David.

[clayliner]

Time for a  few more shots of everyday activity on the B&W (and the local wildlife!)

First, 'Creech' pushes some empty skips up the gradient to the bridge en route to the mine:


P1030740 


'Corfe' and 'Arne' outside the yard at Mill Lane:

P1030729aa


and the little tractor (known unofficially as 'Winston' after its previous owner in the US) shunts some loaded skips into the transhipment shed:


P1030737a



'Corfe' comes off the bridge:


P1030736a


and here 'Arne' shunts some wagons:


P1030733aa copy


Finally, 'Creech' runs down towards the mine to collect another rake of loaded skips:


P1030726a


and 'Corfe' (still waiting to have its nameplates fitted) comes out from under the twin bridges:


P1030743


David.

[Robin Webster]

I just enjoy ever ones talent. I like it. A busy day in the life of the little people.
Robin.