Dismissing all 'OO' 4-wheel tank wagons as looking the same (round ends, 2/3ds length cat-walks, ladders at one end), my heart sank when I read Bachmann were no longer releasing a conical-ended bitumen tank.  

 

However, RMweb always inspires in the face of adversity, and taking the advice of @Fat Controller , I bought some bits and pieces from Mr George Ansell's delightfully 'un-internetty' S Kits firm, and had a go at bodging something myself.  The chassis would be quite wrong, I knew, but I would rather have something reminiscent of a prototype for new traffic in my Goods Yard, than go without until perfection arrives.

 

Picking up some old Hornby TTAs at exhibitions, I bought from S Kits sets of replacement ends, cat-walks, flame tubes, and, unsure which was correct, both flat and conical flame-vents.  I found also a Hornby 'Shell' TTA for sale with ends modified already, so decided to try and make that look like an Ethanol or Methanoic (Acetic) Acid tank for further variation.  Wish I had bought more of them now...

 

Of course, Paul Bartlett's wagon picture web-site was invaluable throughout.  Here are the new wagon ends, with one still attached to the 3D-printer flashing, and the Hornby 'victims' having undergone surgery.

 

 

 

 

 

 

Here are the ends glued on, awaiting Milliput filler.  Only one of the four ends is wonky, which for me is a success.

 

 

 

 

 

 

I was sorry to discover the fine texture of the 3D printing does not disappear under a strong light after spray-painting.  However, without destroying the detail, I know not how to correct this.  Thankfully, the garage is gloomy.

 

Filler added to end gaps and old holes and smoothed down:

 

 

 

 

Flame-tubes, cat-walks, and ladders being attached:

 

 

From front to back: TTV, TSA, TTA (chemicals).  I admit I am chuffed with the latter's 'drip strip'(?) a third of the way up the tank, made simply from 120 g.s.m. folded paper.

 

 

The TTV's full-length cat-walk.  Ooops!

 

 

 

 

Ladder being glued on the TTV (one rung too few, but I can live with that):

 

 

 

 

Ladder on the TSA.  I will need to buy another, as the S Kits fret had only one (for the single end-ladder TTA).  I glued it to a piece of scrap to secure it to the tank side.  The ladder should be longer.

 

 

 

 

And after spray-painting, here they are in revenue earning service (if unrealistically on the same train), delivering fresh bitumen to a tarmac plant on the Sussex Weald, churning out macadam for all those new roads built in the 1970's and '80's.

 

 

 

 

 

 

 

 

The chemicals TTA came out rather 'vivid' with the silver spray-paint, so I must ponder how to tone it down.

 

 

 

May I thank Mr Ansell for his advice on parts to purchase, and RMweb contributors for inspiring unknowingly this little project.  I can cope with the wagons' lack of realism, having no desire to pay nearly forty quid each for newer model oil wagons just to mangle them.

 

Now I need only to wait for someone to produce the correct decals to finish them.  I urge anyone reading this who has not tried such an experiment to do so her/himself.  While the results are not as good as from a manufacturer, it was fun trying.