6. Stage 2- May 2020 The Lift Up Bridge is Redesigned Again

After I put pictures of the MKII design on a Garden Railway forum a question was asked about the pivot height. 

When I revisited the design, I found that when track was attached to the supports there was a yawning gap that just did not work.  The error I made with the MkII was that I put the bridge support on top of the hinge pivot instead of level with it.  When the rail was added the gap was just unworkable as the support folded into it. 

So back to the drawing board for this little project I went and came up with Bridge Design MkIII where the bridge support will now be level with the top of the hinge and will not fold into the gap.

I then built a proof of concept jig to test the design with positive results.

It became apparent that the secret of the opening is having the bridge support level with the top of the hinge and the 45 Degree cuts in the rail which allows the moving rail to drop away from the fixed rail without fouling.
The moving arm of the hinge is level with the baseboard and the gap that the rail folds into is not real wide.

Closed

Open

Closed-Close Up

Open-Close Up

I then started the bridge construction following the concept principles.

The new mounting block has been made from wood and work on the first hinge has started.
Unfortunately I used some hardwood from the $2 per 1.2M rack and it is cut crooked i.e. 32mm on one side and 30mm on the other.

Luckily I have 2 different sized mounting bolts and the longer one just happens to bring the hinge top level with the baseboard.

Next thing to do is the Deck to carry the rail which will be made out of aluminium to keep the weight down.

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5. Stage 2- May 2020 The Lift Up Bridge is Redesigned

23 May 2020
The base boards on the other side of the opening have been completed so work has now started on the Lift up Bridge.

25 May 2020.
I had a rethink about the hinge arrangement on the lift up bridge and decided to make the mounting block out of steel rather than wood.
To make the mounting block I fitted 2 pieces of 'C' purlin overlapping each other and screwed them together to form a rectangular hollow box.

I purchased a more robust set of gate hinges and 2 plastic shims 10 mm thick which when fitted to the mounting block and the timber supports for the bridge were added, the top of the supports was level with the top of the approach base board.

28 May 2020
Another rethink saw the use of timber for the bridge supports replaced with using Aluminium primarily because the hardwood timber was comparatively very heavy and would have made the ease of opening the bridge more difficult.

The bridge supports are now made out of 50mm x 30mm x 3mm Aluminium box section.
They will carry the majority of the weight of the trains and combined with the new hinges are at the same height as the top of the baseboards without the necessity for the 10mm shims which will be used elsewhere I am sure..

Initially the supports crossed the opening at right angles to the ends of the baseboard frames but when track was positioned to check the alignment it became obvious that the supports should be on an angle to allow a smooth alignment for straight track across the bridge.

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4. Stage 2- May 2020 Lift Up Bridge Work Begins

To allow access to the inside of the loop I decided to build a lift up bridge to go over an opening left in a lattice fence that forms the front of the railway.

The Opening

After seeking ideas/suggestions from people who have built these type of bridges on various forums I settled on this idea provided by Korm Kormsen from the Large Scale Central forum.

The main difference is that the hinge mechanism is below the rail as opposed to what appeared to be the norm of the hinge being above the railhead height.

I  started by building the mounting point to which the  hinges will be attached, it is held on by and angle bracket and 2 steel posts concreted into the ground.

Hinge mounting mounting point

I chose gate hinges because they were stronger and more robust then the normal door hinges plus the are galvanised.  
They will have to be recessed into the mounting block so that bridge support is level with the approaches roadbed.

Hinge Closed

Hinge Open

The hinges will have to be fixed away from the end of the roadbed to allow for the bridge to swing up without fouling the end of the roadbed.  A gap slightly larger that the height of bridge support timber will have to be left for the end of the support to fold into.

I will take this part of the build very slowly making sure the the bridge can be opened and closed with confidence before proceeding.
To this end I will have to complete the base boards on the other side of the opening so that is the next thing that will be done.

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3. Stage 2-May 2020 Lattice Fence extended across the yard from Side Fence.

I had 3 lattice panels left over from a renovation so I decided to use them as frontage for the loop as it crosses the yard.
The first panel extends from the side fence to form "Coleus Corner", while the other two extend from the loop access opening across the yard.

This effectively divides the yard and gives the impression that the inside of the loop is a garden in itself rather than just something behind a raised track.

This fence will form the front of the track base board support keeping it the same as "Coleus Corner". 
The finished "Coleus Corner can be seen on the right in the pictures looking into the loop and on the left in the pictures looking out of the loop.

Looking into the loop Coleus Corner on the right

Looking out of the loop Coleus Corner on the Left

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2. Stage 2-May 2020 Inside the Loop Landscaping started

With Coleus Corner now finished I have begun landscaping the inside of the loop, I am laying pathways, building a seating area complete with firepit for colder months and garden beds (using wood chip mulch and shrubs) so that the need to mow can be eliminated in the area.

I laid the border of the garden beds running about 700mm inside the garden edges that I built under the elevated roadbed. 

This border and the garden edges form the sides of a pathway that will allow me to follow trains around the loops with out having to push through gardens.

The space between will be filled with Decomposed Granite (which is sold at landscape suppliers as 'Deco') to form the pathways.

I constructed a ring of retaining wall blocks and filled the centre with gravel, I then added a firepit to sit on top of it. 

 Around the ring I dug out an outer ring 1.5 Metres wide between the retaining wall block ring, and an outer ring to be edged with concrete pavers. This will be filled with same 'Deco' as the pathways to provide a space for seating. 
The seating area will give me somewhere to sit and watch trains just running around the loops while relaxing.

Firepit and surround

Firepit with seating area dug out

To gain access to the inside of the loop I am building a lift up bridge (more detail in another post), which will be at the head of a path that leads to the sitting/firepit area off which will run the pathways that follow the layout.

Lift up Bridge opening with future Firepit path

The Lattice fence will be extended across the yard from the other side of the opening to enclose the inside loop, more on that in another post.

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1. Stage 2-May 2020 Stage 2 Begins - across the yard

Construction of Stage 2 has begun!!

It involves bringing the two tracks at the end of the downhill running around through some curves, with radii of 1.5M (5 Foot) inside and 1.8M (6Foot)outside, and then across the yard into the "town area.
This will create a loop, the inside of which will be accessed via a lift up bridge hinged at one end.

As there are no fence posts to attach to I have had to cut my own and concrete them in, they are made of galvanized "C" purlin (used to build sheds etc).

Benchwork Inside View showing future garden bed

I used a piece of lattice screening that was on my back deck before it was renovated, to provide a finished edge to the railway when viewed from the house. 

The lattice provides a shady spot behind it for shade loving plants.  A garden bed has now been built in front of it with a Frangipani Tree as focal plant.

Lattice Screen

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