GWR A28 and A30 Autocoaches

[WillCav]

Hi all,

 

I've been reading up on A28 and A30 autocoaches and looking at photos of the preserved ones.  I'm thinking of converting an A30 into an A28 for some variety on the layout.

 

I have some questions:

 

1. Were the inner end windows plated over on all the coaches before 1949?

 

2. What differences are there - so far I've found 7' bogies and flush driver doors on the A28 - is there anything else I've missed?

 

Thanks in advance 

 

Will

[The Johnster]

Q1; Not 100% certain, but the huge majority were certainly plated by then.  I would avoid having van end windows on any BR liveried autotrailer without dated photographic evidence of established provenance (of course, GW liveries survived for several years post-nationalisation).  
 

Q2; watch out for bogie positioning.  The 7’ bogies were pivoted each one foot closer to their respective ends of the coach, and this needs to be replicated correctly on your model to avoid buffer-locking and clearance issues from excessive end-throw on sharp curvature (and of course for it to look right).  Conversely, with the 7’ bogies pivoted correctly, there will be greater central inward overhang on such curves, again possibly raising clearance issues.  Shouldn’t be a problem unless you are using setrack, but you need to be aware of it.  
 

Assuming the A30 donor is an Airfix-type RTR, there will be a scale foot of excess space between the inner ends of the bogies and the underframe trussing, and possibly some of the other underframe detail as well, especially the dynamos.  Of it were me I’d prolly live with it until awareness of the anomaly eventually goaded me into correcting it; you might be more decisively tolerant, or alternatively wish to pre-emt this!

 

Sone A28s used on Pontypool Rd-Blaenavon (period spelling) trains had modified upper driver’s door handrails because of limited clearances on that route.  

Edited July 14, 2023 by The Johnster

[Hal Nail]

 

[The Johnster]

IIRC.

 

A27 - 57'6" all-steel Collett design with 7' bogies, flush drivers' doors, and flush windows.

A28 - 59'11" all-steel Collett design with 7' bogies, flush drivers' doors, and recessed windows.

(A29 - rebuilt panelled ex-SRM)

A30 - 59'11" all-steel Collett design with 9' bogies, recessed drivers' doors, and flush windows.

 

Or something along those lines...

[WillCav]

8 hours ago, The Johnster said:

IIRC.

 

A27 - 57'6" all-steel Collett design with 7' bogies, flush drivers' doors, and flush windows.

A28 - 59'11" all-steel Collett design with 7' bogies, flush drivers' doors, and recessed windows.

(A29 - rebuilt panelled ex-SRM)

A30 - 59'11" all-steel Collett design with 9' bogies, recessed drivers' doors, and flush windows.

 

Or something along those lines...

Thanks for all the replies.

 

I've had a look at the Airfix underframe and compared it to the A28 diagram in Russell's GW coaches book.  The diagonal part of the trussing will need lengthening for A28 as you hinted at.

 

I did think about an A27 but the amount of cutting and shutting looks scary. If only someone did a brass side overlay.

 

Thanks

 

Will

[Coach bogie]

1 hour ago, WillCav said:

Thanks for all the replies.

 

I've had a look at the Airfix underframe and compared it to the A28 diagram in Russell's GW coaches book.  The diagonal part of the trussing will need lengthening for A28 as you hinted at.

 

I did think about an A27 but the amount of cutting and shutting looks scary. If only someone did a brass side overlay.

 

Thanks

 

Will

I have shown this before, but here is my A28 from a pair of scrap Airfix autos. Once the bogie centre had been altered you do not notice the truss rod lengths in my opinion. Looking at photographs of the real thing it is not obviously a different length from the A30, especially if you fit all the gear to the underframe. That is where most of the work is. This was an experiment to see if it could be done for less than £20 - it was.

 

Mike Wiltshire

[Coach bogie]

2 hours ago, WillCav said:

Thanks for all the replies.

 

I've had a look at the Airfix underframe and compared it to the A28 diagram in Russell's GW coaches book.  The diagonal part of the trussing will need lengthening for A28 as you hinted at.

 

I did think about an A27 but the amount of cutting and shutting looks scary. If only someone did a brass side overlay.

 

Thanks

 

Will

There is this etch for sale at CPL for £35. one etch found in a clear out.

https://www.cplproducts.net/latest-news.html

[Hal Nail]

2 hours ago, Coach bogie said:

Once the bogie centre had been altered you do not notice the truss rod lengths in my opinion.

It's a similar story with the E140 and E145 B sets, which had the same body, one with 7 foot and one 9 foot bogies, which were discussed on the Rapido thread. Eventually it was decided the truss rods are different but it's barely noticeable unless you really compare closely.

Edited July 16, 2023 by Hal Nail

[The Johnster]

In the case of the E140-E145 conversion, you are replacing 7' bogies with 9' bogies rather than the other way around, which might mean that the 9' bogies foul on the trussing, a point to watch out for.

 

There are various oddities regarding bogies with autotrailers, especially those rebuilt from SRMs.  I have two of the Keyser whitemetal A31s, which came with two different passenger vestibule doors (according to where they were built; Swindon built had 'normal' doors, GRCW outsourced had double doors; the kit has the latter but comes with American bogies, which none of the Gloucester builds had), and three different types of bogies (presumably whatever was on hand when they were rebuilt from the SRMs), fishbelly, American, and Collett 7', but on the original pivots, so the bogies were unequal distances inward from the ends of the coach.  Several SRM rebuilds have this feature, particularly noticeable with Collett 7footers.

 

Funfunfunfunfun...

[Hal Nail]

12 hours ago, The Johnster said:

Several SRM rebuilds have this feature, particularly noticeable with Collett 7 footers

I'm doing a 70ft conversion from an N to an L in 7mm and at least one of these had 7ft bogies which I might chose as it kept all its panelling into BR era. I'll have to check back now but I think the pivots were actually moved on that one. As usual under GWR standardisation there is no one rule!

[lofty1966]

You can easily cut out the doors and set them flush on the Hornby/Airfix model but on the inside you will probably require some plasticard as the joint is wafer thin.

The Hornby old style Collett 7ft bogies are offset from centre so you can use them without to much fuss

[lofty1966]