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Building 'Tantalus' - Part Three


MikeOxon

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At the end of the previous Part, I wrote that I intended to turn my attention to the chassis. Before that, I had broken off from work on the chassis, to give some thought to the problems posed by the curved splashers over the driving wheels.

 

Now that I have proven the technique of ‘hybrid’ construction, combining traditional etched brass model-making with 3D-printing, I’ve decided to pursue similar methods for the chassis. For wheels, I recovered a spare set from a ‘Mainline’ Dean Goods that I converted into a 2-4-0 ‘Stella’ a few years ago. My conversion was described in the April 2013 issue of ‘Railway Modeller’, These wheels have larger flanges than are desirable, so I shall probably replace them at a later stage but they are useful for setting the clearances for the splashers.

 

Rather than relying on measurements, I prefer to base my models on ‘templates’ that are derived from the actual components that I am using. In this case, I laid the chassis, with wheels attached, in my flat-bed scanner and made a scale image as the basis for my drawings

 

Tantalus-scan.jpg.4a00289eeecbd69f1c215e33d4036ac5.jpg

Scanned image of mainframe and wheels

 

I then ‘pasted’ this image as a background layer in my drawing program and drew the splasher outlines to fit around these wheels. I transferred my 2D drawing into ‘Fusion 360’, where I used the ‘push/pull’ tools to extrude the tops of the splashers so that they would ‘frame’ the wheels.

 

The resulting 3D model only took a few minutes to print, so it was easy to run off a test-print and check the fit before proceeding any further. This proved worth while, since my first print was a little too shallow to leave clearance for the valance to fit in front of the wheels.

 

While considering potential refinements to my initial print, I realised that some other features could be added to the footplate, including the tops of the springs, which appear from behind the splashers, and the sand-boxes, which are placed alongside the smoke-box. After adding these additional features, my 3D model appeared as shown below.

 

Tantalus-3D-splashers.jpg.2c1387ab343502ca3dbde284039a062a.jpg

3D model of splashers with springs and sand-box

 

I extended the backplane of the print slightly below the top of the chassis, to provide a ‘tab’, so that the splasher assembly could easily be glued to the back of the mainframe.

 

One very welcome feature of 3D printing is that, in order to produce the splashers for the opposite side of the engine, it is only necessary to click on the ‘mirror’ command and the appropriate part is created automatically.

 

Once both sides had been printed, I glued them to the sandwich mainframes and inserted the boiler assembly between the frames, as shown below:

 

Tantalus-assembly.jpg.b0f2f3eb51101d3fdfdad454c3e0e932.jpg

Hybrid brass / 3D-printed model of ‘Tantalus’

 

It was now time to turn back to brass construction and I cut out the etched valances provided in the BGS kit and glued them to the outer edges of the splashers to give the result shown below:

 

Tantalus-valance.jpg.95c996de0398cf2b52bb635086b04433.jpg

‘Tantalus’ after adding etched-brass valance

 

There are still many details to be added but I think my model has reached the stage where it allows the rather ‘gawky’ appearance of these early Broad Gauge engines to be appreciated.  This might seem to be a short post but most of the work was in the planning - the actual printing and assembly only took a few minutes :)

 

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  • RMweb Gold

Oooh, very nice!  At the risk of stating the obvious, as you say those are large flanges. I assume you've taken that into account with respect to the splashers.

 

Incidentally I like the brass and brown combo. Maybe it's my 1970s childhood coming back to haunt me, but I do like brown as a loco livery.

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You were quick off the mark, Mikkel!  The splashers are actually touching the flanges at present.  I had intended to turn them down in my electric drill but the rims are loose on their centres so I'll have to buy replacements.  If I need to make a tweak to the drawing it won't be difficult, anyway.

 

The brown and gold does look very 'up market' - a gold and fine-leather look.  Perhaps I should polish it and leave it like this :)

 

As with all Broad Gauge engines, there's a yawning gap between the fames, so I shall have to make some gear to fit in there.  Another mental exercise!

 

 

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That most certainly is a very nice Tantalus, and better looking than this one . . .

An ex is navy victory ship, bought by the Blue Funnel Line and renamed Tantalus, similar to the gwr, Blue Funnel named all their ships after characters in Greek mythology, but for them they were exclusively from the odyssey, which was the favorite book of the Holt brothers, the line founders.

5E8B97BC-1455-4F36-A89B-B8AB9E35EF26.jpeg

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  • RMweb Gold

Tantalus is looking splendid!  I’m really enjoying how you combine modern technology with traditional modelling methods to achieve all this.  Looking forward to the next instalment :)

 

BW

 

Dave

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12 hours ago, Florence Locomotive Works said:

That most certainly is a very nice Tantalus, and better looking than this one . . .

An ex is navy victory ship, bought by the Blue Funnel Line and renamed Tantalus, similar to the gwr, Blue Funnel named all their ships after characters in Greek mythology, but for them they were exclusively from the odyssey, which was the favorite book of the Holt brothers, the line founders.

 

Mention of the Blue Funnel line takes me back to childhood.  I remember travelling on the Liverpool Overhead Railway and seeing all the different shipping lines in the docks - Blue Funnel and Bibby Line both spring to mind but there were many others.  The end came quite suddenly, as the old Empire trading routes collapsed.  Knowledge of classical literature also seems to have collapsed, although those Greek writers understood at least as much about human nature as we do today.

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6 hours ago, MikeOxon said:

Mention of the Blue Funnel line takes me back to childhood.  I remember travelling on the Liverpool Overhead Railway and seeing all the different shipping lines in the docks - Blue Funnel and Bibby Line both spring to mind but there were many others.  The end came quite suddenly, as the old Empire trading routes collapsed.  Knowledge of classical literature also seems to have collapsed, although those Greek writers understood at least as much about human nature as we do today.

Unfortunately as I’ve only been on this Earth nye on 15 years, so I have been deprived of such sights. Thankfully my grandfather a native of Liverpool went to sea in the early 60s, first with Brocklebank line to the Far East, and then as an Engineer on RMS Queen Mary in her last year of operation. He talks a lot about the overhead railway, especially how it looked like some half dead dragon after bomb damage.

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Extremely interesting work Mike, mastering the 3D printing has certainly opened up a whole new approach to your models.

 

Please excuse me if I've missed it anywhere, may I ask how you intend to power the locomotive ?

 

Quite a few years ago I was trialing a build with Heather Kay for the BGS,  producing the motorised tender for the Rover in 4mm and which certainly opened up the means to add detail to the "underbelly" without compromising the final kit.

 

The tender certainly works and has quite some weight too, all helps.

 

G

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3 minutes ago, Florence Locomotive Works said:

Unfortunately as I’ve only been on this Earth nye on 15 years, so I have been deprived of such sights. Thankfully my grandfather a native of Liverpool went to sea in the early 60s, first with Brocklebank line to the Far East, and then as an Engineer on RMS Queen Mary in her last year of operation. He talks a lot about the overhead railway, especially how it looked like some half dead dragon after bomb damage.

I have 60 years over you!  I see from your profile that you have an aspiration to model the Broad Gauge.  It's a fascinating subject so I hope you get there.

 

I have many childhood memories of the bomb damage in Liverpool, which took many years to repair.  The road alongside the docks was lined by tall blackened walls of burnt-out warehouses - a rather nightmarish scene but, as a child, I was always pleased to see the small dock steam engines and, best of all, one of the steam lorries that were still around.

 

Mike

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10 minutes ago, bgman said:

...

Please excuse me if I've missed it anywhere, may I ask how you intend to power the locomotive ?

...

The tender certainly works and has quite some weight too, all helps.

 

You've not missed anything - much of my work is purely experimental at present.  There's plenty of room in a wide BG firebox for motorisation but I am quite a fan of tender drive and have used it several times on NG models.  I have more engines than tenders so have arranged plugs, so that I can swap them around (just as the GWR did in the real world)

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3 minutes ago, MikeOxon said:

I have 60 years over you!  I see from your profile that you have an aspiration to model the Broad Gauge.  It's a fascinating subject so I hope you get there.

 

I have many childhood memories of the bomb damage in Liverpool, which took many years to repair.  The road alongside the docks was lined by tall blackened walls of burnt-out warehouses - a rather nightmarish scene but, as a child, I was always pleased to see the small dock steam engines and, best of all, one of the steam lorries that were still around.

 

Mike

I remember one of those steam wagons in the Liverpool Museum when I visited family there about 7 years ago. My 7 year old mind though it was the coolest thing ever. I believe they were all super sentinels, with fully enclosed undertype engines and vertical boilers, some capable of 50 mph.

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  • RMweb Gold

Certainly coming along Mike.  Very clever not trying to print it all in one go but to make a kit of parts.  Will it be motorised or will it just go in the diorama?

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The honest answer is I don't know.  As I mentioned in an earlier reply, tender drive is a possibility, as a single motorised tender can be shared amongst different engines.  Since I've not built any sort of BG layout yet, a diorama will certainly come first.

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Mike,

 

Excellent and inspiring work.  I have come to the same conclusions about 3d printing and locos.  My current musings centre on producing a 3541 and Hawthorn 2-4-0t.  I'm thinking about 3d printing the tanks, boiler,smoke box etc, probably the bunker (or having it as a former around which brass sheet is bent.  My plan - based on drawing up a D0 parallel boiler and cab for a SG Dean Single - is to print the cab front, but have brass side (to get them as thin as possible.  As to the footplate, I think the valences, as you have done, must be brass, but I'm thinking about a 3d printed sub frame over which a brass footplate is placed (splasher clearances being a problem area), and which will provide a means of locating the valances very precisely too.

 

Regards

 

Duncan

Edited by drduncan
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Thank you fir your comment, Duncan.  I think the template idea is good and it was my experiments in that direction that led me to my current way of working.  I find that my PLA prints cleanly at 0.5mm (20 thou) thickness and is surprisingly tough.  When I built 'Rob Roy', I made brass splashers but the valance was Silhouette-cut card with a metallic adhesive film stuck to it before cutting.  It has stood up to time surprisingly well.

 

In my present model, the brass-tube boiler provides both rigidity and weight to the whole structure, leaving 3D-printing for those parts where surface details are wanted.  I could even add a 3D-printed sleeve to represent the cladding and boiler bands!

 

Mike

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On 02/05/2020 at 10:50, Florence Locomotive Works said:

I remember one of those steam wagons in the Liverpool Museum when I visited family there about 7 years ago. My 7 year old mind though it was the coolest thing ever. I believe they were all super sentinels, with fully enclosed undertype engines and vertical boilers, some capable of 50 mph.

7529 At rest

The one closest the camera is the one my grand-dad bought and had restored in 1959.  Yes, those ones were Super's, but there were some of all the Sentinel products still around at that point.  One of the largest by # of late fleets was of standard (pre 1921) waggons used in a steel mill.  

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On 12/05/2020 at 15:21, peach james said:

 

The one closest the camera is the one my grand-dad bought and had restored in 1959.  Yes, those ones were Super's, but there were some of all the Sentinel products still around at that point.  One of the largest by # of late fleets was of standard (pre 1921) waggons used in a steel mill.  

I seem to remember that the standards had some sort of false stigma around them of unreliability, but this was actually the opposite?

Edited by MikeOxon
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2 hours ago, peach james said:

 

The one closest the camera is the one my grand-dad bought and had restored in 1959.  Yes, those ones were Super's, but there were some of all the Sentinel products still around at that point.  One of the largest by # of late fleets was of standard (pre 1921) waggons used in a steel mill.  

 

Thank you for the photo, peach james

 

A Sentinel could be seen at North Leigh, long after my modelling period, when the quarries had become a source of gravel and the old forge and barn were a general yard.

 

1016677359_Sentinel_NorthLeigh.jpg.6c1e4ff78261e0518a1a2c3ebdf858c1.jpg

 

Mike

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