7mm Heybridge Basin

[Richard Gawler]

I must admit I do keep looking at your layout/diorama with a view to plagiarism for a small O scale opertating diorama .

The only thing which keeps putting me off at present of the use of baseboard kits is their use of apparent heavyweight materials and construction to withstand earthquakes. With this in mind I always keep looking at aircraft wing design and construction to see if I can build strong lightweight baseboards.

Mk2 Yaris before I extended the front and back of the module


Mk3 Mazda 2

At the moment, Heybridge Basin complete with its track, wiring and point mechanisms but without scenics or backscene weighs 4.1 kg. This is a Grainge and Hodder baseboard with home-made extensions front and rear.

I am finding the module easy to carry around the house and take in and out of the Mazda. This would get difficult with a permanent backscene, but I want the backscene to be detachable so it can pass behind the extension for the sea lock.

The front and rear extensions of the model are sturdy enough to work as handholds, but I'd like to add a handle along one long edge. This can wait until later, when I know where the C of G has ended up.

 

[Richard Gawler]

I started to write about ballast here and on my Workbench topic but this was a bit premature. It is sensible to deal with the groundworks built directly onto the baseboard before adding any ballast.

I have made a start on these with the passenger platform.


I have made the transverse pieces in two parts. This way there is no accurate cutting needed except to get the outer ends square.


I overdid the depth of one kerf on the first front wall and it snapped. The second attempt has at least twice as many kerfs as I really needed. I got away with fewer cuts into the rear wall because the edge trim (below the cardboard finishing strip) is holding this piece into shape.


The platform will end up higher than I really wanted it to be, but this way the coach doors will open underneath the awning. The long lens has closed up the hoizontal gap between platform and lower footboard, this will end up about a scale foot. Passengers will use an upturned wooden box or portable steps to climb in and out.


The platform is a scale 64 feet long to hold two 30 ft coaches with a little leeway. I have used an entire 2.4 m length of 11 x 6 mm stripwood to build this.

When I glued in the last piece I thought about the fall (run-off) on the surface to let rainwater drain away. This would have been really easy to do with some packing under one long edge. On the other hand, the finished surface will probably be ash or gravel so no great need for this. And it will be easier to fix the building upright onto a level platform.

 

[Richard Gawler]

I have been digging into railway standards to find a sensible slope for a platform end ramp (1993: "no steeper than 1:8") and realised a real railway would build their station platforms on straight track if at all possible. Platforms should include some extra length to allow for stopping errors too.

I went for a curve because I thought it would look better, and barely more than the exact length because two-coach trains will be rare. But I wonder if I would do the same now I know a bit more about platforms. Hmmm.

 

[Yorkshire Dave]

I went for a one coffee stirrer height platform on an operating photo diorama (based on an early photo of the Brill branch before the Met rebuilt the platforms).



The building was a spare scratch built wood shell based on the Met Brill branch which I used for an experiment with the Redutex textured self adhesive building sheets and roof tiles. Trackwork is Peco O scale setrack and the photo was taken in the evening sun.

 

[timbowales]

I went for a one coffee stirrer height platform on an operating photo diorama (based on an early photo of the Brill branch before the Met rebuilt the platforms).

View attachment 216287

The building was a spare scratch built wood shell based on the Met Brill branch which I used for an experiment with the Redutex textured self adhesive building sheets and roof tiles. Trackwork is Peco O scale setrack and the photo was taken in the evening sun.

What’s the backstory for the name?
Tim T

 

[Richard Gawler]

It looks like absolute madness to me. And particularly well-executed.

 

[daifly]

What’s the backstory for the name?

It's Italian. Google the translation and smile!
Dave

 

[Richard Gawler]

Progress has been sluggish this week and probably seems a bit haphazard, but I have managed photos of four new things.


The passenger platform is getting ramps at both ends. These were a requirement of the BoT and I don't think I will add much character by missing them off. They are reasonably short because the platform is (in current parlance) only two coffee stirrers high.


The extension for the sea lock gives me a baseboard joint to practice on. The setts are Wills ones sold for 4 mm scale but representing courses about 120 mm wide here. The white strip is putting back what the saw blade took away, and the sticky tape is keeping glue out of the joint.


I have vague aspirations for a second extension to the left so I've added some stripwood to close up the joint here. Again, the tape is keeping glue away from mating surfaces.


The buffer stop now has a block of wood inside and a woodscrew underneath holding it down. This arrangement will help if I move the buffer stop to another layout or, of course, in the unlikely event I want to repaint it.

I have a good chance of making all of the landscape from sheet cork and foamboard, which will save on the mess and weight of plaster.

 

[simond]

I’d certainly avoid plaster - card formers, woven card strip, covered with ripped green paper towels glued down with PVA works pretty well. Very light, resilient, easy to change if you decide to add or delete festures.

 

[Richard Gawler]

I have now stuck down two thirds of the setts for the inset track.


Construction is much like what I would do for a smaller scale except I am using stripwood instead of thick card. The Will's sheets seem to be strong enough to span small gaps. The running rails are higher than the setts so I can clean the track without spoiling the scenics, and the outer setts have a fall to let the rain drain away.


The surveyors have arrived! After all my efforts with Evo-Stik between styrene setts and underlying copperclad and card, this piece still eased itself upwards.


I am glad I have gone for 0-MF with its 1.5 mm flangeways. If I can paint the inner rails to tone with the setts, the flangeways should look quite neat.


I want the front area to connect with the edge of the basin, but I'm happy with the overall effect so far. I think the layout will look less cluttered with these rails set into the ground surface.

 

[Richard Gawler]

I went back to Heybridge Basin on 5th June, mainly to measure the coping stones but I did get to see the sea lock operating. So here are some photos as a distraction because modelling the coping stones and basin edges is going to take some time.


The sluices in the outer gates have been open for a while and the sea lock has drained into the estuary. The outer gates are now opening, and an effect of this is to make the water surface calmer.


This is the location of the gate I need to model for my diorama. I have no idea what the Victorian gates looked like, so I might just copy the essence of this one with timber in place of the steel.


The flood gates (beyond the lock gates) are power driven but the lock is worked manually.


The sea lock often takes two or three veseels, but today I saw just this one.

 

[Yorkshire Dave]

Canal lock gates are of broadly similar construction throughout the country.

For The Chelmer and Blackwater Navigation lock gates I'd just go further inland to to say Beeleigh Lock. There's a nice photo on the Institute of Civil Engineering website https://www.ice.org.uk/what-is-civi...ngineers-do/chelmer-and-blackwater-navigation

This diagram and image are from The Grand Junction Union Canal website.





Might be worth hunting early images of the locks on the Crinan Canal as this was built to enable Clyde Puffers to navigate.

 

[Yorkshire Dave]

The sea lock often takes two or three veseels, but today there was just this one.

On busy days the lock keepers/operators will cram as many in as they can depending upon the vessel size to minimise water waste. When sailing with my neighbour on the Crinan Canal I've seen up to six small vessels in a sea lock.

 

[oldravendale]

Just out of interest, and a side issue of no relevance to this thread, I'm familiar with the sea lock at Shoreham. It's the only one with which I'm familiar where the gates are opened before the water has reached equilibrium. On a good day there's a tidal wave when the gates are opened although the water level when the gates are opened seems to depend on the nature of the boats in the lock. When it's fishing boats there seems to be no concern with allowing a couple of feet of water in to the lock in one go. Those hydraulics must be mighty strong! Here's a not very good video of the lock in use. shoreham sea lock - Google Search

Brian

 

[Richard Gawler]

For The Chelmer and Blackwater Navigation lock gates I'd just go further inland to to say Beeleigh Lock.

Before I go to Beeleigh, I can get some design cues from Pipps Ford lock on the Stowmarket Navigation (River Gipping). The design engineer here went on to build the Chelmer and Blackwater.


This is the upper end of the lock. It's easier to comprehend the brickwork on a disused lock without any gates.


This is the lower (downstream) end of the lock. The arched recess intrigues me. The upper end of the sea lock at Heybridge has a rebate in much the same location, but extending all the way up to the coping.

All these photos taken 26 April 2024.

 

[Yorkshire Dave]

The recesses are probably to accommodate the paddles when the lock gates are/were open.

 

[simond]

I guess the deeper recess is for the sluices and their operating gear?

but the upper picture suggests they’re on the downstream side of the gate, and I’m dubious about that…

Edit - crossed with Dave’s post.

 

[Richard Gawler]

The recesses are probably to accommodate the paddles when the lock gates are/were open.

I agree.

I guess the deeper recess is for the sluices and their operating gear?

but the upper picture suggests they’re on the downstream side of the gate, and I’m dubious about that…

The weir seen in my upper picture (at the head end) is a modern construction to control the river after the lock was taken out of use. I expect the sill remains, but submerged out of sight.

To be honest, I'm only really interested in modelling the head end of the sea lock. The remainder will be off-scene, beyond the baseboard.

Some canal locks have a ground paddle upstream of the gate at the head end. This allows water to flow through a tunnel to an outlet downstream of the sill, to fill the lock. Pipps Ford might have had these (with the visible equipment being lost), but the sea lock at Heybridge Basin does not, so this is one less detail to worry about. The paddles at Heybridge Basin are built into the gates, two in each gate.

 

[Richard Gawler]

The diorama now begins the transition from a fanciful little thing to trying to capture a real location. The honeymoon is over.


The side of the basin juts out to provide a space for a vessel to wait while others using the sea lock go past. I have ignored this up until now but having done my latest site survey I will include it as a gesture towards Heybridge Basin. So the head end of the sea lock moves right to make space. I will omit the 20th century apendage on the corner.

Starting this now lets me decide the decide the finished ground levels between inset track and basin edge, and confirm the height of the model water. On the prototype, the water is just below the bottoms of the coping stones.


A scale dawing didn't work out so I cut out rectangles to represent the coping stones and arranged them onto card.


Then I rearranged them onto 4 mm ply and cut this to suit.


Vertical supports from more ply.


Further surfaces are foam board and card. I need to find out or guess the horizontal location of the sill, I hope this ends up closer to the gates.

Along the way, I have been thinking of making the sea lock as an museum style model rather than a scenic model. I won't be wanting to take many train photos here. This model is pretty much to scale in the horizontal plane (I measured most of the coping stones!), but it is compressed vertically at least 20 - 30 mm. This lets it fit onto the front of a 100 mm deep baseboard module, but it doesn't really look right for a basin supposedly dredged to two metres or more. The lock gates will end up too shallow as well.

So - there is an opportunity to represent the construction of the lock; or hide the worst of the vertical distortion with a translucent water surface; or possibly use clear perspex to leave the parts fully underneath visible.

(Edited to add the prototype photo, hoping this will make the post more intelligible)

 

[Richard Gawler]

The irregular section of basin in the last post gives me the surface structure to let me finish off the inset track. This has all been a bit exasperating because of the calculations for the copings to go along the edge of the basin, but it is done.


This approach all started because I had most of a pack of Will's embossed setts to hand and I could use it up here, but being 7 mm scale I had nowhere near enough so I had to buy a second pack.


The inset track is on a slight curve and so the courses of setts behave just like the rails of flexi track.


This prompted me to extend the paving and use up the rest of the setts. I have plenty of card, but never the right thickness.


My first go on the layout with DAS modelling clay. This is laid on a bed of *wet* PVA and embossed with the back of a knife when partly set.

I have vague memories of trying DAS years and years ago but I cannot remember the project let alone the year. I primed the surface with PVA and let it dry. I laid the DAS and this dried and promptly fell off, and I put the DAS in the bin because clearly the magazine where I read this was Wrong. This was of course before the Internet and forums. Thanks George @Herb Garden and all I can add here is "me too".


The main thing for me (the engineering part of me) is the baseboard joint, this ought to look okay on the finished layout.