Jump to content
 

A new ‘Old Engine’- Re-visited


MikeOxon

1,023 views

I find it hard to believe that more than six years have passed since I started to build a model of one of the early standard gauge engines, transferred to the GWR when they acquired the Oxford, Worcester, & Wolverhampton Railway (The Old Worse & Worse, as it was colloquially known)

 

I have been reminding myself of what is in this, my older ‘Pre-Grouping’ blog, before I changed over to (became obsessed with) the Broad Gauge!   My model of No.184, shown below, was the last model I built using traditional methods involving brass sheet. It also sat on the first ‘chassis’ I built – a simple pair of brass strips separated by ‘Markits’-type spacers.

 

GWR_184_model1.jpg.f04d8d2fb201d6185f6e4c89d39b313a.jpg

My model of No.184, photographed in 2014

 

Although the overall construction went quite well, I made a silly mistake with the underframe and ended up with outside frames that were too wide to allow free rotation of the outside cranks, while clearing my platforms!  As a result, this pretty little model languished in my spares box for many years, although I did attempt a partial rebuild in 2017, when I also finally got around to building a Tender.

 

Nevertheless, I still felt dissatisfied with the model and it all seemed a bit of a kludge. The boiler fittings never felt quite right, either, since I was reliant on the nearest matches I could find from the trade, being unable to construct my own components.

 

GWR184_NorthLeigh2.jpg.d5bc98a8a18b0c26e4480ed9fea1d727.jpg

 

No.184 with old 4-wheeers at North Leigh

 

While reading through my old articles, I found I had written the following prophetic words in one of my replies to comments: “I'd like an affordable3D printer so I could keep everything in my own hands “ Well, a lot has changed since November 2014 and not only are there plenty of low-cost 3D-printers around but I have also got to grips with some of the problems involved in using CAD modelling tools!

 

The first task was to sort out those outside frames! I was amazed to find how tough it was to dismantle those parts I had  re-made in 2017.  The lengths of Broad Gauge rail that I used to re-make the edges of the footplate un-soldered reasonably easily but the filler I had used in various places was as hard as rock and had to be ground out with a drum sanding-disk in my mini-drill, which produced clouds of white dust everywhere!

 

Looking at those hand-cut outside frames, which I was very pleased with at the time, they look rather crude now, with barely a right-angle corner in sight!   For rivets, I had used the brass rivet strips that used to come from ‘Mainly Trains’ but are now still available from ‘Wizard Models’. I built up a stock when ‘Mainly Trains’ closed and have used them for all sorts of things including a standard-gauge Tilt Wagon.

 

I still had all my original drawings of No.184, so all I needed to do in order to make a new set of 3D printed frames was to import the appropriate drawing into ‘Fusion 360’ and trace over the lines, then extrude the new frames. Adding rivets is a breeze since @Timber pointed out the ‘pattern’ tool in ‘Fusion 360’.   I simply create one rivet head and copy as many as I need along a chosen direction!   I think the overall design took about an hour and then I could transfer the model file to the ‘Cura’ slicer software, to produce a file for my printer.

 

 

58861965_3D-printovercanvas.jpg.91b4682531d4281567f5706fe85f68f4.jpg

3D model over drawing ‘canvas’ in Fusion 360’

 

The complete set of frames took 33 minutes to print and now I had nice ‘square’ openings for the axles boxes, smooth lines of rivets, and correct spacing between the outer surfaces of the wheels and the inner sides of the outside cranks.

 

614278610_3D-printedframes2.jpg.e7131a961af9d7b6313728888899ecc3.jpg
My 3D-printed frames on the printer bed

 

The funny thing is that at normal viewing distances, it really doesn’t look any different!   (i’ve deliberately kept the image small to emphasis this point).   It does, however, now have adequate clearances for the outside cranks.

 

1278553849_newframes.jpg.12cdf50bcf6c6b7f0d5ce5a3544dfb87.jpg
New outside frames in place below my original model

 

Sometimes, I feel I want to re-make all my old models by means of the 3D printer but, when I look at them, they bring back many happy memories of the time I spent creating them in the ‘old ways’.  It’s easy to be hyper-critical and see all the faults in the old constructions but, in practice, they look fine and they each have a ‘history’ attached to them. I shall resist the temptation to re-do everything and, instead, will concentrate on new and different prototypes, especially those which reveal something about railway history but are unlikely ever to be appear in the model marketplace.

 

Mike

  • Like 11
  • Craftsmanship/clever 3

7 Comments


Recommended Comments

  • RMweb Gold

Good to see No. 184 receiving an update. Those frames look so crisp in the close-up, impressive.

 

I can see what you mean not wanting to update the rest, it would never end! 

  • Like 1
Link to comment

Thank you Mikkel.  It was just something that suddenly occurred to me - that I could correct No.184's problems with a simple 3D-print fix! 

 

I also discovered that small features, such as rivets, print more cleanly in the vertical plane than when the part is laid horizontally.  When horizontal, there is a tendency for filament to 'string' between adjacent features although careful adjustment of 'Cura' settings can minimise this.

  • Informative/Useful 2
Link to comment

As an Addendum to this post, I put my model of No.184 he to head with my model of the Broad Gauge Gooch Goods.  the size comparison is remarkable!

 

793260120_Broad-NarrowCompare800x600.jpg.53357c8127691787e653d0cd5276ac27.jpg

 

Mike

  • Like 2
Link to comment

That's a good comparison, Mikkel.    Joseph Armstrong's '111' class had very similar wheelbase to the absorbed E.B.Wilson engine No,184, which I modelled. 

 

A very significant difference in the size of Broad Gauge engines was the height allowed by the BG loading gauge.  A maximum height of 16 feet on the Broad Gauge vs only 12' 10" on Standard Gauge.  It really shows in the chimney heights of BG engines

 

The Gooch Goods itself looks smaller against the 'Waverley' class 4-4-0, mainly because of the difference in boiler pitch:

 

Waverley-Goods_comp.jpg.51672de7a4bf99be036cec2781c06f2e.jpg

 

 

Mike

 

 

Edited by MikeOxon
  • Like 2
Link to comment
  • RMweb Gold

Ah, very nice. I do like the petroleum tinge you have arrived at. Apart from being well reasoned, it also suits them well.

Link to comment

Thank you Mikkel.  The colour is similar to that of a 19th century model that I first saw in the Pitt Rivers Museum in Oxford many years ago.

 

742766836_Eagle_PittRivers2010800x600.jpg.fea403f3124289453e228fb2bff19f56.jpg

  • Like 3
Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...