When "that'll do" just isn't good enough.

[John Candy]

I had been gifted some parts, which included parts for a laser cut brass cab, from which to build a  GWR 2251 class 0-6-0  (often referred to as the "Collett Goods").
That will save some time (or so I thought) and will come in useful for Monkton Priors.
When measured up against the Swindon GA it became obvious that there were major dimensional (and profile) errors in all the components.
The attached photo illustrates the degree of the errors (the cab sides are also "way out").

The photo shows the cab front supplied, laid over the replacement being cut from brass sheet..... the divergence from prototype is more than a little obvious!

WHY is it that the producers of larger scale products seem to think that "near enough" will do when it comes to garden railway items? Is it so difficult to "get things right"?  60 years ago it could be forgiven that models were often not exact replicas (drawings were probably more difficult to source, so approximations were rife).
Today, such gross errors would be fatal for the success of a kit (or major component) in the smaller scales, where it would be picked upon and criticised, pretty quickly, in the model railway press and in online discussion groups.

I don't know the provenance of the parts involved here but have my suspicions , since I know of only one supplier offering parts for a 2251 cab (if I am correct, the parts involved would have cost around 30GBP at currently listed prices). Those parts are said to have been prepared from drawings supplied by a well-known G3 supplier who has been criticised previously (in this forum) in respect of serious errors in other loco drawings.

Regards,
John.

[Chris_P]

Not sure how the 2251 compares with other GWR locos for height but I'm just wondering if the supplier was thinking in terms of a cut down cab for running main line?

[John Candy]

GA shows "12ft 5ins rail level to top of cab"......using the supplied part would give 12ft approx.
By way of comparison, GA for 43XX Mogul (Churchward cab) shows 13ft 1.5 ins while that for 48XX (0-4-2T) is 11ft 11.75ins (a Collett cab). This suggests to me that the producer of the 2251drawing (as used for the model parts) failed to check the GA and made the incorrect assumption that the height was same as for the small Collett tank locos.

2251 was a "yellow route" power class B (BR 3MT) loco.

Regards,
John.

[MikeWilliams]

Maybe the designer didn't have access to the GA and used a modellers' drawing which was wrong.

Mike