Connect 3 - new drawing for download

[IanT]

Members will be aware that we have been developing a simple way to interconnect G3 baseboards and track 'sections' that we have called 'Connect 3'. This comprises a plate which is attached to the end of the baseboard or track section and which is positioned using a removable 'jig & track gauge'. This allows the plate to be attached relative to the top and inside rail datum, which means that tracks using different baseboard thicknesses and rail sections can be easily connected together.

I'm planning to use Connect 3 as a way of building a portable track using track 'sections' (big Hornby!) that can be put up in the garden – but that can also attach to visiting track sections or even exhibition or portable layouts.  I'll talk about this more in the June Newsletter.

To this end we produced six prototype sets of laser cut components and gave these to Members with exhibition layouts and asked for comments. The feedback was that the 'Jig' needed to be 20mm deeper to effectively position the plate 20mm lower. This gives more room for thicker baseboard, sleeper and rail sections to be accommodated. We can then connect Society rail with white metal chairs, our ABS sleepers and GRS track on thicker baseboard material.

It may be worth mentioning that by a very simple modification to the 'gauge' component - the Connect 3 system can be used to connect other gauges below 63.5 mm – for instance 45 mm and 32 mm.

Our intention is to produce laser-cut stainless steel plates at a reasonable price but anyone who wishes to make their own plates is welcome to do so. This would require careful marking out but one of the design aims was to make the plate as simple as possible. You could probably make the plate in aluminum, Perspex or even ply – but they might not wear as well as steel. An updated dimensioned drawing for the three components required is now available for download by Members – from the 'Members Only' section – please note that you need to register separately from the Forum to access this part of the site.

The web address is: http://lakes-pages.com/gauge3orguk/members/Connect3.pdf

[keith Bristol]

This is very much of interest as having a smaller garden I was planning to make a couple of removable sections to appease the planning aurthorities. The production of this jig means that i can make much more use of the sections.

If you are having a batch made. I will have one as with building a purpose made shed over part of the railway means I wont be manufacturing my own this side of christmas.

[IanT]

We will have to see what level of interest there is Keith.

As I've said, part of the idea was to make the 'Plate' a component that could be laser-cut with no 'after-work' required, such that they could be mass-produced and costs could be kept low. Any complexity is in the 'Jig & Gauge' (and there's not that much there) and since they are only used to position the plate (and we have six sets already built) it may be that we can set up a loan system - such that you buy the number of plates you need (one for each 'end' of track) and once you've screwed on your plates - you return the Jig to the Keeper. What a great job for someone, with a title like "Keeper of the Society Jigs - by Appointment" 

Anyway - I will put more thoughts in the June Newsletter - and ask for some feedback from Members in the Forum - so we will see what interest there is from that.  Regards

[Derek King]

Ian,

As I have already mentioned elsewhere, when I eventually get round to building a G3 layout it will be a small, hopefully semi-portable, one and therefore I will plan to utilise "Connect 3" to join the baseboards to allow for any future expansion or even joining up with others. If the Jig does becomes available with interchangeable track gauges as discussed, then I would probably buy rather than loan to also use on my 7mm layout.

One query - in the March Newsletter writeup you state that two plates set edge-to-edge will automatically provide a scale 7ft clearance between dual tracks. But surely the '7ft-way' was normally only utilised in storage/marshalling sidings with the norm for dual tracks, both main lines and in goods yards and coal sidings being a 6ft clearance. Therefore may I suggest that the connecting plates are modified to allow for the normal 6ft clearance with "slip plates" also made available to accurately set both the 7ft clearance and the 10ft clearance (between main running lines and sidings) as required.

This leads me to another question, in O Gauge the 6ft, 7ft & 10ft clearances are nominally allowed for by standard dimensions of 80mm, 90mm and 110mm respectively between track centres. Do we have such nominal measurements in G3 or do we work to the scale measurements of 150.8mm, 164.3mm & 204.8mm respectively?

Derek

[IanT]

Hi Derek,

You are correct, in that dual track clearance was normally 6' between inside rails (as measured from the 'rail' centre) with this distance being increased (as I understand it) to 6' 6" somtimes in the early 1970's. However this clearance was increased on curves (by an unspecified ammount as far as I can discover). So the original Connect 3 design did actually provide for a 6' clearance but after some discussion I decided to increase it to 7'. There were several reasons for this.
The foremost was that I felt a "single" standard spacing was required - in other words a universal fit - and also that I wanted a simple way to do this e.g. two 'plates' that abutted to each other and therein you get a 'twin-track' plate (you only use the outside bolting holes). The idea is that the plate defines the standard - so I didn't want to introduce any variables.
Secondly - there was the problem of 'standard' curves. In practice the clearance needs to be widened on curves (especially tight ones) and it gets complicated if you start trying to 'transition' between straight and curved track sections. So this further suggested a wider clearance as the norm.
Finally - there are quite a lot of model steam engines out there (and probably coaching stock too) that don't completely meet the scale loading gauge - I saw an engine "clang" the top of a bridge at Tenterden a few weeks ago - and knowing Adrian - the bridge would have been the correct height!
So a compromise was made - effectively adding 1/2" (13.5mm) between inside rail if you assume 6' clearance and 1/4" if you assume 6' 6". In my view wasn't going to be a problem in a Garden setting given the advantages set out above. Also to answer your last question - a very small 'rounding ' has occured to provide clean measurements. The clearance as set up is 95mm (7.03' at 13.5mm) - this assumes a proto rail width of 2.75" (70mm) as an "average" for most bullhead rail used.

[IanT]

Just had a second "thunk" about that last statement - trying to remember what I actually did quite some time ago when I did the original drawings. The 'plate' is 160mm wide. The gauge is 63.5mm (as measured from the inside rails). The difference is therefore 96.5mm. At 2.75" a 'scale' bullhead rail (at 13.5mm) will be 3.09mm wide. However I halved this on my 'back-of-an envelope' calculation just now (to get to a rail 'centre') - and I shouldn't have done that as I was dealing with the full width of the plate (if you are following me?) :-)

So just to correct my last statement - unless I've managed to confuse myself again - it's 96.5mm - less 3.09mm - which is 93.41mm - or 6.919' (giving a scale 6' 11" clearance) to be accurate. However I still feel that in practice (certainly in the Garden) this increase is really not going to be noticeable. There are after all plenty of Members using out-of-scale rail sections from a well known supplier and personally I rarely notice that these days.

[Derek King]

Ian,

Thanks for the explanation, I can fully appreciate the need for the increased clearance in the "Garden" situation and the desire to have a standard one size fits all. I only raised the issue because, as stated in your March Newsletter writeup, your idea was born out of the option for "small" individually built indoor (electric) layouts to be connected together at exhibitions to allow 'end-to-end' running.  I had thus assumed that the builders of such layouts would normally be railway modellers "up-scaling" from the smaller scales who would wish to take advantage of the larger G3 to build to "scale" proportions.

Therefore in answer to my last point on nominal track centre line measurements can Members assume that the G3 Standard for a pair of tracks, be it main running lines, yard sidings or storage roads is 160mm. This still leaves the need for a Standard nominal measurement for the 10ft clearance between running lines and sidings if we are to ensure compatibility between base boards.

Finally for the record, in accordance with my sources of information  (NERA's "North Eastern Record", Slaters' "Track Construction without Tears" and Iain Rice's Finescale Track manual), the 6ft (and other) clearance between a pair of tracks was measured from the outer edge of the rail - not the centre. Therefore the 160mm between track centres with 63.5mm gauge and scale 2.75" bullhead rail (3.09mm) will give a clearance of 90.32mm which equates at approx 6ft 8.25", a slightly better compromise!

Regards,

     Derek.

[IanT]

Hi Derek,

Well - where to begin? First let me say that I have always assumed that 'board' sections would fall into two catagories.

First there are those that were designed to be connected to other specifc (to that layout) sections - where the track connection can be anything the builder desires - because they already know where the track intersects and what type of rail, sleeper etc has been used. Connect 3 could be used in these situations but is unlikely to be so in my view (there are simpler/cheaper ways to do it).

The second is where the builder does not previously know "what" they are connecting to and requires a 'standard' to do so. This is where Connect 3 comes in - but at this time - I would suggest that only the very minimum standard can be set and that is in terms of single and twin track connections. There is nothing to stop you having two single connections that are a scale 10' apart - but that is what they would be - two connections - and the single track sections connecting into it would have to be narrow enough to sit side by side if you see what I mean. The 'Hornby' track sections I also mentioned in the March NL would be usable in this scenario - because they are 'plate' width. This would not fit in with the 'grid' concept that I will outlin below though.

In terms of the exhibition layouts I had in mind - they tend to be station 'terminals' with a single track fiddle yard on one end. So Connect 3 would extend the fiddle yard and could connect two such terminals, making for more interesting running (at an exhibition or not).

However - there is more to the concept than just the Connect 3 Jig/Plate - and I had intended to expand the idea further in the June NL with some thoughts on some 'standard' track geometries and planning grids. For instance - if designs were based on a 2' (or 600mm?) square 'standard' grid - you could designate an 18' by 4' grid as "custom" but still design in standard "in & out" connections that met Connect 3 requirements (from Qty 1 single-track - up to Qty 4 twin-track Connects). It maybe needs some diagrams to explain fully, but hopefully you get the general idea. I hope this at least partially answers your questions - I will try to get the detailed concepts into the Sept NL - and then we can debate it further and throw it open for suggestions.

With respect to where the clearnace measurement is taken from - I always thought it was from rail centre - but I am happy to stand corrected by higher authorities.  Regards,  Ian