Laser Cut Catenary Portals

[wombatofludham]

Sounds like a very fair appraisal.

Thanks. I tried to describe them as fairly as possible as clearly they would be of interest to some. I think the key thing is I do feel they would struggle to carry much in the way of detailed wiring and supports and one thing I did forget is if your installation would be prone to knocks, or visits from "companion animals" they could be easily damaged, although at the price and if not glued into the foundation pads, relatively easy and cheap to replace. Unfortunately one fat furry pussy could flatten a couple of these masts.

 

Just as an experiment, I think after I've entertained the masses on the Dolgellau layout over Easter I might have a go at designing and 3d printing a suitable dropper assembly, not with the aim of stringing up wiring but to finish off the structure as a scenic, non-wired item. I'm just curious as to how it might work out, and a 3d printed lightweight plastic wiring support might not add too much weight, so watch this space.

[Guest teacupteacup]

Thanks. I tried to describe them as fairly as possible as clearly they would be of interest to some. I think the key thing is I do feel they would struggle to carry much in the way of detailed wiring and supports and one thing I did forget is if your installation would be prone to knocks, or visits from "companion animals" they could be easily damaged, although at the price and if not glued into the foundation pads, relatively easy and cheap to replace. Unfortunately one fat furry pussy could flatten a couple of these masts.

 

Just as an experiment, I think after I've entertained the masses on the Dolgellau layout over Easter I might have a go at designing and 3d printing a suitable dropper assembly, not with the aim of stringing up wiring but to finish off the structure as a scenic, non-wired item. I'm just curious as to how it might work out, and a 3d printed lightweight plastic wiring support might not add too much weight, so watch this space.

A fat furry pussy once ruined my mast....    (fully expect this to be removed but couldnt resist it!)

Edited April 13, 2018 by teacupteacup

[Clive Mortimore]

Some drawing to help with the height of the mast.

 

These are examples where the catenary wire is under the bridge.

 

And where it goes over the bridge.

 

[D86]

Just to let you all know that there is now an alternative laser cut offering from Scale Model Scenery. I've just purchased a pack of 10 which are going on my layout. Here's a link to the website.... https://www.scalemodelscenery.co.uk/product-category/oo-4mm-176/catenary/?v=79cba1185463

 

I have modified them slightly, to remove upright girders at the ends of each section and cut away one of the straight girders that would have been attached to the post. 

 

[James90012]

They look great to me. I'm just wondering about how to model the 'droppers' or the actual wire contact points - do you plan to add these?

[bescotbeast]

They look great to me. I'm just wondering about how to model the 'droppers' or the actual wire contact points - do you plan to add these?

I have to agree, those look very much like the real thing, I may have to invest in one or two

[Titan]

Just to let you all know that there is now an alternative laser cut offering from Scale Model Scenery. I've just purchased a pack of 10 which are going on my layout. Here's a link to the website.... https://www.scalemodelscenery.co.uk/product-category/oo-4mm-176/catenary/?v=79cba1185463

 

I have modified them slightly, to remove upright girders at the ends of each section and cut away one of the straight girders that would have been attached to the post. 

 

DSC_0875.jpg

DSC_0883.jpg

 

They are not bad! I wish in real life we could just lift up a bridge and stick a block of wood under it!

 

It would look really good if you could just lower the wire instead, but then that would rule out poseable pantographs as they would not get under it, if that is your intention.

[D86]

I've not sorted out the bridge properly as yet....just messing around with the wood to see where I need to be. Most certainly work in progress.....I've pretty well demolished the old trackplan and started again, but using the existing scenery in most parts.

 

Okay, here's a few more shots. I've actually been making the registration arms etc and fitted them this morning. I'm using 3/64 and .032 Brass Rod to make them....along with solder twisted around the rod to replicate the insulators. Crude, but it works for me. As you can see, there are three N-Brass portals already on the layout. They are of the light portal variety. I'd say that the Scale Model Scenery kits are the heavy duty type. 

 

Steve

[Dagworth]

I've not sorted out the bridge properly as yet....just messing around with the wood to see where I need to be. Most certainly work in progress.....I've pretty well demolished the old trackplan and started again, but using the existing scenery in most parts.

 

Okay, here's a few more shots. I've actually been making the registration arms etc and fitted them this morning. I'm using 3/64 and .032 Brass Rod to make them....along with solder twisted around the rod to replicate the insulators. Crude, but it works for me. As you can see, there are three N-Brass portals already on the layout. They are of the light portal variety. I'd say that the Scale Model Scenery kits are the heavy duty type. 

 

Steve

Those look good, but you have fallen into the same trap that I did. The equipment will normally be on the side of the portal facing the direction of traffic for the line it supplies, not all on the same side.

 

Andi

[D86]

Those look good, but you have fallen into the same trap that I did. The equipment will normally be on the side of the portal facing the direction of traffic for the line it supplies, not all on the same side.

 

Andi

Thanks for that Andi, really appreciated. I'll make sure that they're all correct from now on. I never even gave it a thought.

 

Steve

[44690]

Thanks for that Andi, really appreciated. I'll make sure that they're all correct from now on. I never even gave it a thought.

 

Steve

Andi,

 

Can you please explain that in simple terms for my benefit? Sorry to appear stupid, but I am not familiar with OHLE. I've looked at the pictures and your explanation, but I'm not sure where D86 has gone wrong. I was thinking of building a small layout with some electric locos and catenery, but it all looks a bit too complicated for me. Perhaps I should stick to the steam era with which I am familiar. Lol.

[Clive Mortimore]

Andi,

 

Can you please explain that in simple terms for my benefit? Sorry to appear stupid, but I am not familiar with OHLE. I've looked at the pictures and your explanation, but I'm not sure where D86 has gone wrong. I was thinking of building a small layout with some electric locos and catenery, but it all looks a bit too complicated for me. Perhaps I should stick to the steam era with which I am familiar. Lol.

Hi 44690

 

The registration arms are dangled towards the traffic that is trying to push them along the track. I think a photo is the easiest way to show someone, here is one taken at Witham in Essex. From left to right the registration arms that hold the contact wire in place are over the following tracks, Up loop, Up main, Down main and Down loop. The two Up registration arms are on our side of the mast and face the traffic going to London the other two are on the other side and face the traffic going to Colchester.

 

[Titan]

Matching the direction of traffic may be coincidental. They alternate to even out the loading, particularly the torsional loading of the boom.

[44690]

Hi 44690

 

The registration arms are dangled towards the traffic that is trying to push them along the track. I think a photo is the easiest way to show someone, here is one taken at Witham in Essex. From left to right the registration arms that hold the contact wire in place are over the following tracks, Up loop, Up main, Down main and Down loop. The two Up registration arms are on our side of the mast and face the traffic going to London the other two are on the other side and face the traffic going to Colchester.

 

Thank you Clive.

 

I think I understand the explanation now. I must admit I had to read the explanation a couple of times and study the picture. Out of curiosity, how would that work on bi-directional lines?

 

Ian

[njee20]

Sounds like Titan's explanation covers that - it's not to do with running direction, rather they simply alternate. Often this will coincide with running direction, but obviously wouldn't in places the lines are configured US/UF/DF/DS.

 

Appears to be supported by this photo, where the registration arm on the US is 'facing' traffic, whilst on the adjacent UF it's 'trailing'.

 

[Clive Mortimore]

Sounds like Titan's explanation covers that - it's not to do with running direction, rather they simply alternate. Often this will coincide with running direction, but obviously wouldn't in places the lines are configured US/UF/DF/DS.

 

Appears to be supported by this photo, where the registration arm on the US is 'facing' traffic, whilst on the adjacent UF it's 'trailing'.

 

The portal mast shown on this thread represent Mk1 OLE. When I was doing my research on Mk1 OLE in few of the 20 odd 1960s BR documents I read it was recommended that the registration arms are attached to the side of the portal bridge that faces the on coming traffic. I neither have the time or the inclination to read them all again to show where I found it. All the documents were found on a railway documents achieve site. Go and look at Mk1 OLE before it all disappears.

 

Three random BR drawings of Mk1 portals all showing a solid line for the down line registration arm dropper and a dotted line for the up line registration arm dropper where it is behind the portal. They all show the registration arm on the facing side.

 

Mixing UK 1 equipment, Mk3 or any other system with the Mk1 is like wanting to put a Mk1 suburban coach in an HST.

 

Most of the documents covered such exciting topics as "Blow Off". I will let Ian show the formulae relating to "Blow Off"

[Titan]

Baked Beans + cabbage = blow off.

[D86]

A little more progress on the Catenary.

[Trog]

I seem to remember that there should be a mast so many feet from a switch toe to control the wires for the two routes as they diverge/merge.

 

 

Found something

 

Handbook 49 ideally mast to be where the divergence between the switch and stock rail is 200mm. (150mm min, 380mm maximum.)

 

That is about 7m in from the toe on a Bv switch and 8m on a Cv. (-1m or +3m for the less than ideal positions.)

 

 

PS Note that on a sharp curve like the photo above all the registration arms would be pointing towards the inside of the curve, as they are pulling the wire outwards to keep it in line with the track. On straight track they would tend to alternate in direction to zig zag the wire as that evens out the wear on the pantograph carbon.

Edited June 24, 2018 by Trog

[ianmacc]

Regarding the original product, I’ve taken a punt on three packs of these as the price suits those with a large layout on a budget. I’ll take some pictures in situ in due course. A coat of grey lifts them already..

[ianmacc]

Trial fitted them but haven’t bedded them in to the scenery yet. Look good enough for the impression of catenary from a few feet away. They are fragile so I’m keeping the spares I have because I suspect a derailment will take them out!! Easy enough to bash into different configurations as they’re only fibreboard so cut easily.

 

As supplied they span double track straights at set track geometry but third or less radius fouls them; especially with long stock such as BR Mk3s.

Edited January 17, 2019 by ianmacc

[ianmacc]

Raided the office stationery cupboard and fashioned a few dozen paper clips into rather basic approximations of droppers. Fit some rudimentary insulators next, identity plates and paint the droppers and that will do for me.

 

Used some repainted triang single masts for bay platforms etc.

 

Finescale? No! Reasonable and an excuse to buy some 80s era electrics? Yes...

 

Ps no matter how I rotate the images they always seem to appear sideways!!

Edited January 24, 2019 by ianmacc

[Pete the Elaner]

Raided the office stationery cupboard and fashioned a few dozen paper clips into rather basic approximations of droppers. Fit some rudimentary insulators next, identity plates and paint the droppers and that will do for me.

 

Used some repainted triang single masts for bay platforms etc.

 

Finescale? No! Reasonable and an excuse to buy some 80s era electrics? Yes...

 

Ps no matter how I rotate the images they always seem to appear sideways!!

 

Your masts look great.

 

Catenary is hard to get nice & fine in OO because it would be extremely  fragile. I remember speaking to Andi Dell (Dagworth) a few years ago & he told me that all his pantographs had their springs weakened until they could just about support a very short pencil. This was to reduce the gauge & tension of the contact wire to something more aesthetically pleasing. Standard Hornby pans are way more fierce than this.

Painting the arms & wires dark grey helps to hide them. I know the copper goes a light green colour but this is one of the occasions where I believe the correct colour is not the best thing to use.

 

You mention that stock fouls them on curves. We all have to use train set curves to get our layouts to fit & Mk3s are always likely to give the most problems. Check the distance between the track & mast against in the photos in post #40 & in Clive's diagrams. Ignoring the Diesel line in the bottom diagram, the dimensions provided by Clive show a minimum 11' from track centre to mast centre. Yours look 7' at most. This is probably too much of a major change to apply, but possibly something to consider for a future layout.

[letterspider]

I've just seen this thread while looking for advice on how to fix register arms to these MDF lasercut portals.

I think they very useful option for modellers wanting to try out catenary - you get 10 of these for the price of one Peco double gantry.  I can see why Bescot can be irritated about them not being to his satisfaction but it is going to be a far less expensive experiment than all the other options out there.

 

Sometimes it is the potential cost of the failures which we have to keep an eye on!

 

I agree they may look rather tall once assembled but I intend to use them on a viaduct section and alongside platforms, so that may well turn out to be an advantage if it is true.

 

Anyway - back to the modelling

 

- I have been able to source some very fine insulators with a hole about 0.5mm running through them (from Aliexpress)

Now I am thinking about making the registration arms (I am working in OO gauge)

 

The longer arm would be straightforward but I don't know the typical diameter of the pole on the prototype- it looks about 6 inches to me in photos - which would be 2mm

so that is my first question - what is the diameter on the prototype?

 

So my second question -

Brass is easier to solder than steel but I am not confident the horizontal arm would have sufficient stiffness. Can I get a strong solder joint in steel? Can I solder steel to brass? To begin with I know I will need to get Carrs flux for steel.  

 

I will be using epoxy resin to form a strong bond between the arms and the MDF and also to give some volume to the bond and some suggestion of a mounting bracket.

The third question relates to the top wire of the catenary. In the photos I have seen and from what I remember, the suspension wire is usually going through a pulley - is that necessarily the case?

 

Any advice would be really appreciated.

 

Ade

 

 

 

 

 

 

Edited December 27, 2020 by letterspider

[nhdesigns]

I've just come across this and would like to add my view on these laser cut Catenary Portals. I've probably got the ones mentioned from a site on Ebay called Torri Laser cutting and Design. I mainly got them after seeing a post on Facebook and a video of how to model registration arms.

 

I've made a set before from N brass locos and played around in these laser cut ones. In my own opinion and for simplicity I would say laser cut portals of the heavier type are a lot better. Mainly for the ease of building them, which only takes a few minutes with some strong glue than special solder flux for brass and a hot iron. And from what I've seen, adding registration arms are easier to fit with just super glue than soldering.

 

I did that last year with my N brass portals and ended up with everything coming apart!