Showing posts with label Flettner Ventilators - AV426 Retrofit. Show all posts
Showing posts with label Flettner Ventilators - AV426 Retrofit. Show all posts

Saturday, December 14, 2013

AV Dining Car - Roof Detail

 

 
 In recent times I have been asked by some members of our group about how I achieved the roof detail and its positioning on my model of the AV Dining Car. This was a problem that I faced back in early 2010 when I was looking to complete my own model of AV 426.
 

 WAGR - AV 426 Dining Car Model
 
Whilst discussing my problem with Rob Clarke who is a member of the ARHS Museum, it was suggested that we could go and measure the real thing at the museum. The agreed day arrived and I met Rob (who had come armed with a ladder) at the Museum and we climbed up onto the roof of AV 425 and carefully set about the task of plotting the positions of the roof equipment.
 
Here is a few prototype pictures showing what is on the roof
 
Kitchen End Stove Vents to right
Looking from Kitchen End over Dining Room
 
Kitchen End showing Galley Vents to left
 
Ok now that you have an idea of what is on the roof, next is to provide the important measurements  & modeling tips. All measurements shown are in millimeters. I have calculated these from the actual 1:1 measurements to suit placement onto the model.
 
To begin with you need to mark out the centerline of the roof.
 
As shown in Picture 1 below - From the kitchen end, measure and mark the positions of the standard Flettner ventilators that run the length of the coach.  
 
 
Picture 2 shows the position of the Stove vents using the first Flettner vent at the kitchen end as the start point for locating. First measure and mark the offset line and then mark the vent positions.
 
  
Picture 3 Shows the location of the Galley Vents again using the first Flettner vent at the kitchen end as the start point for locating. Measure and mark the offset line and then mark the vent positions.
 
 
On the roof I used WestOzModels Flettner Vents for the standard centerline vents
 
 Railwest's brass large carriage vents were used for the stove vents.
These need to have mounting plates to enable them to sit level on the curve of the roof and can be made from laminated styrene sheet or perhaps an old style knitting needle or similar solid rod sliced and filed to suit the arch of the roof. 
 
For the Galley Vents and Water Filler (on the Bullnose end) I used some styrene sheet circles cut to size with a smaller circle with the edges filed or rounded off and then glued on top of the larger circle to represent the lid on top of the mounting plate. To fit on the roof, some light filing with a rounded file will be needed on the bottom of the vent to suit the roof arch particularly on the bullnose end.
 
Here below is a close up picture of the Water filler. The Water filler and the Galley Vents are very similar being mounted with a 6.34mm diameter base. The diameter of the "Lid" is 5.35mm for the Galley Vents and 4.56mm for the Water filler.
 
Water Tank Filler
 
Another feature amongst the Galley vents is the long rectangular vent. Whilst the earlier coaches seem to have been fitted with 5 round vents, it would seem that a longitudinal vent was later fitted presumably for better air collection whilst travelling.
The picture below shows these vents fitted to AV 425,426 & 286. Note that the version on 286 is low and flat compared to the round top versions on 425 & 426.
The measurement for the long vent on AV 425 is 9.52mm Long, 4.36mm wide and 3.37mm high.
I constructed this from 4 sections of 2.5mm sq Evergreen strip styrene glued together and then filed to shape and then I used a dremel with a sharp point bit to mark in some vent veins on the ends
Long Vent
 
Hopefully the information I have provided above will help you all to be able to complete those dining cars you have been working on.
 
As with all of the WAGR carriages there are many variations with fittings etc that will always present us as modelers with a challenge. As always it is best to find a good picture of the prototype you are modeling and follow what you see.
 
A big thank you goes out to Rob Clarke for his assistance with access and measuring of the roof  fittings on AV 425. I promised Rob at the time that this info would be shared with all who may need it and thanks to this blog it has now been possible in a better way than could have been imagined at the time.
 

Friday, October 14, 2011

Flettner Ventilators - AV426 Retrofit

Flettner Spinning Ventilators were one of the more modern fittings used by the WAGR for attempting to create an airflow through the roofs of coaching stock to assist with cooling during the summer period. The Picture below shows two vents on top of the real AV426From a modelling point of view these ventilators are a very important part of producing a model which "looks the part" - in real life we only see these items from ground level, but with a model they are the first thing we see as we look down on our models from above.

Initially when I built a couple of coaches with these vents on the roof I opted for the easy and basic use of a slice of leftover Kadee coupler sprue which gave a good representation (as can be seen in the next picture) but that was all - I was happy with the result but I knew it could be better. After the show this year I started to produce the AZ kit (see elsewhere in blog) and decided it would be nice to be able to not only do the early version but also the later modernised versions which would need to have the Flettner Ventilators and lots of them - far too time consuming to make individually, and so I started down the path of producing a pattern for casting.


In S scale these vents are 3.75mm diameter and 2mm deep making them a very tiny and fiddly item to produce. After much cussing & time fiddling around, a pattern and mould was made enabling casting to begin.

And so I hereby present the WESTOZ MODELS - Flettner Ventilators.
The Picture above shows the vents on the roof of the AV dining car at the museum with the available 12pk of WESTOZ MODELS vents, and a much magnified view of the cast vent.


The view shows the bottom of the vent. Modellers need to gently sand the 'Top" of the casting to remove excess casting flash. This is best done using a fine sandpaper such as 400 wet and dry. "Care must be taken" to ensure an even sanding and not to heat up the vents with heat from fingers - as with any urethane casting they will bend with heat.


To show off these vents I figured I should retro fit one of my existing coaches and so AV426 was chosen - the pliers gotten out and the old vents twisted off the roof. Dont worry I cringed just as much as you probably did reading this, but it had to be done, even at the expense of potentially wrecking a perfectly good model. This next picture shows the old sprue vents removed from my AV dining car& the new Flettners in place and ready for paintingCast onto the bottom of the vent is a flat raising tab which will lift the vent just off the roof surface to give the impression of it not sitting flat on the roof - Place a small dob of glue on this tab an locate on coach roof - allow to dry and then paint. The above picture and the one below show the finished refit of AV426 with the Flettner Ventilators - Now to do the rest of my coaches!


As these vents were widely used on many different classes of coaches, hopefully they will make a very useful item for WAGR S scale modellers, enabling more coaches to be completed and "Look the Part" from above.