7mm At the Western End of F7

SimonT

Western Thunderer
A further exploration of the accuracy of the VBA:
Width - Prototype 8' 10" Model 9' 4"
Length over headstocks - Prototype 33' 6" Model 34'
and from before
Height - Prototype 12' 31/2" Model 12' 9"
Anyone seeing a pattern?
 

demu1037

Western Thunderer
A further exploration of the accuracy of the VBA:
Width - Prototype 8' 10" Model 9' 4"
Length over headstocks - Prototype 33' 6" Model 34'
and from before
Height - Prototype 12' 31/2" Model 12' 9"
Anyone seeing a pattern?

Talking of 6 inches, that's how much taller than a VVV the VAA is - which was what started this!
 

mickoo

Western Thunderer
Simon, even at 12' 9" it should still pass under the normal loading gauge which is about 13' 3" I think, will the 37 go into the shed without getting scalped?
 

ZiderHead

Western Thunderer
1951 W5 loading gauge states 13'6" max roof height and 15' min bridge height above the railhead. If the shed was built in the C19th the loading gauge could have been much smaller then ;)
 

SimonT

Western Thunderer
The building is an industrial workshop, so the BR Loading Gauge is unlikely to apply. The old 12T vans slide in and out easily. I won't take the 37 in without feeling the need to make a loud dong sound
 

Dog Star

Western Thunderer
I can't find the pictures now, but to my mind they were a bit flat on the sides, the doors don't project far enough beyond the chassis.
Information from Brian Daniels that early samples of the HJ completed cargowaggon van and cargowaggon flat would be on show at the Warley exhibition prompted Peter and I to visit the show armed with various measuring sticks. I understand that these samples are those which were to be seen at Telford; Brian expects production samples to be displayed on the Tower Models stand at the forthcoming Reading Trade show. With Brian's assistance we were able to compare the van and flat to BR diagrams (e512 and e502 respectively... although I am not sure that e502 is correct for the flat wagon).

Interesting results:-

Cargowaggon van
* width over doors:-
  • prototype 2540mm;
  • scale 58.3mm;
  • model 58.1mm.
* length over body:-
  • prototype 20460mm;
  • scale 470.35mm;
  • model 470mm (measured over body end panels).
* height rail to roof:-
  • prototype 3946mm;
  • scale 90.7mm;
  • model circa 90mm (model resting on flanges).

Cargowaggon flat

* width over body:-
  • prototype 2500mm;
  • scale 57.4mm;
  • model 56.3mm.
* length over body:-
  • prototype 20460mm;
  • scale 470.35mm;
  • model 470mm.
* height rail to top of stanchion:-
  • prototype 2950mm;
  • scale 67.9mm;
  • model 69mm (model resting on flanges).
* height rail to buffer centre:-
  • prototype 1060mm;
  • scale 24.35mm;
  • model circa 26mm (model resting on flanges).

Conclusions?

The flat wagon passes muster. OK, there is a discrepancy between the scale width and model width, I am not sure that I have made a valid comparison as I am not clear what the BR diagram book is showing as the width of 2500mm. We shall be keeping our options on pre-orders for this model.


The van is a puzzle... Martin (@Pugsley) suggested that the body side was "thin" by reference of the face of the side relative to the headstock. The HJ sample measures to within 0.2mm over body width so the body is not "thin" (0.2mm represent an error of less than 0.4%). Martin's comparison is valid so I am drawn to the conclusion that the headstock is too wide! As the body can be removed from the underframe by the removal of four screws I feel that adjustment of the headstock can be made without damage to the body (and this suggestion depends upon getting appropriate prototype measurements).

As of now, we are reviewing our options on the Cargowaggon van.
 
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Tony West

Western Thunderer
1951 W5 loading gauge states 13'6" max roof height and 15' min bridge height above the railhead. If the shed was built in the C19th the loading gauge could have been much smaller then ;)
Not always so....the loading gauges of the GNR, MR, NSR and CLC were 13ft 9" vertical as compared to the MS&L later, GCR at 13ft 5"....just thought it worth a mention......
 

Pugsley

Western Thunderer
The van is a puzzle... Martin (@Pugsley) suggested that the body side was "thin" by reference of the face of the side relative to the headstock. The HJ sample measures to within 0.2mm over body width so the body is not "thin" (0.2mm represent an error of less than 0.4%).
That's interesting to know, and also the best way round, really. It's going to be a lot easier to chop width out of the underframe that the body, if you so desire.
 

SimonT

Western Thunderer
The refinery buildings on the ARSE just don't work for me, so I have tried a range of different facilities to replace them. Mock-ups were made of a large transshipment shed with crane, a scrap yard and finally an aggregates pad. This aggregates pad is now the the firm favorite but success depends on there being suitable wagons to run the service. Not finding anything that satisfied me, I dug out some articles by Phil Eames from my DEMU membership days. These featured some excellent drawings by Colin Craig and in particular lots of information on the wagons that interested me, the PG004A diagram. A week of CAD work has traced the 2D drawings and some 3D work this weekend has got me this far....
PGA.JPG

This will all be done in mixed media. 3D prints of everything shown above and the various fittings such as the pedestal suspension. Etched artwork for all the plates work, such as the platforms. Sprung suspension will be provided. The PG004A seems to come in three flavours; platforms at either end, a different design of platform at one end only and some vehicles with no platforms, so plenty of variety on the layout.

Now back to the mouse!

Simon
 

mickoo

Western Thunderer
Kewl, good choice of wagon...and industry.

The PGA family is large and flavorsome, no idea what 004A diagram looks like but snapped these a few years ago at Redlands Baylham discharge site, about the only common factor was the PGA code!
IMG_0687.jpg IMG_0692.jpg IMG_0693.jpg IMG_0696.jpg IMG_0702.jpg IMG_2664.jpg

You may also be interested in the RAIB report of the Ely Dock junction derailment, although not PGA there is a fair amount of detail about the pedestal suspension units and their likely cause in several derailments, some reasonably detailed drawings at the end of this form of suspension that might help you with details etc.

https://assets.digital.cabinet-office.gov.uk/media/547c9030e5274a42900001af/090127_R022009_Ely.pdf
 

SimonT

Western Thunderer
Mick,
thank you, some very useful leads. I suspect that the first wagon is to diagram PG013G but I have yet to work out what diagram the second one is with the conventional brake lever. The drawings in the report will be very useful.

I suspect that working discharge might be a bit too difficult.;)
 
Looking forward to see some progress on the PGA's.

I've drawn most of the PGA's and printed a couple.

PGA%204%20types_zpsk1g0oaj2.jpg

IMG_18202_zpsddd5bf41.jpg

PGA%204_zpsovdvea8a.jpg

Also working on the Redland self discharge train but dont think I'll get it working although the conveyor wagon will be positionable.

DSCF2428%202_zpsfq54cjcu.jpg

DSCF2431%202_zpso73tav3i.jpg

I did get a printed working Gloucester suspension but it was a bit complex and didn't work perfectly.

2DSCF1337.jpg
 

SimonT

Western Thunderer
Simon,
thank you for your interest; I found your work 'on the other side' during a google for anything on the PGAs. Very impressive. The more I look at the PG004As, the more variation I find. There are also variations on the pedestal suspensions.
I have an estimate for printing the complete model at my favorite top quality 3D printers that, as expected, made the eyes water - just too many layers. I am now looking at either:
  • Cutting up the hopper to print as four flats.
  • Printing the chassis and making the hopper as an etch.
There was always going to be an etch to make the platforms. ladders and hopper control gear. Printing the chassis is probably the most effective way of reproducing the massive nuts and bolts that attach the suspensions to the chassis. I am still working on sprung suspension; the hopper stops me having my favorite long springs.

Meanwhile work has started on the iron ore hoppers that I need for Aberbeeg. I have obtained the Railway Modeller that contains the drawing of the Charles Roberts vehicles. There are no dimensions to support this drawing and when scaled to the correct wheelbase, it doesn't match the dimensions of the Dia 1/161 and 1/162 which it should. I am trying to work out where the error is.

Simon
 
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