GWR AA7 toad

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

GWR AA7 toad

Postby Guy Rixon » Mon Mar 23, 2015 9:01 pm

Over the last couple of weeks I've been gradually building a Connoisseur Models kit for an AA7 brake-van. These vans were the short (16 ft O/H, 9 ft W/B) ones used for the trips over the Metropolitan to Smithfield depot. Structurally, they were compressed versions of the familiar AA3 vans.

It's a lovely kit. Everything seems to fit, there are tabs and slots where needed, instead of floating-in-mid-air joints, and not too many overlays; although, ironically enough, I'll be adding a few overlays of my own making. It's such a nice thing to build that I'm making it last and not rushing! I'm making a few upgrades to the kit as I go, but nothing that needs radical surgery.

Here's the carcass with the main, structural work done and some of the etched detailing.

IMG_1130.jpg
IMG_1131.jpg


The T-pieces on the sides are structural: they locate the solebars, so they have to go on early. The bases of the T's are etched in the plane of the planking while the stems of the T's are separate pieces located with slots and tabs. The fasteners on the bases of the T's are represented in the kit by half-etched dimples to be pressed through. I've done this on the corner angles but not on the T's as I want to make shim overlays to get the T's to appear outside the planking: this is quite noticeable in photographs of the full-size vans and notably lacking on photos of the built kits, nice though those models are. Leaving out the rivets/bolt heads/whatever here also makes it much easier to clean up after soldering.

Build time up to this point was about 3 hours.

The missing bit of structure on the body is the verandah floor. This couldn't go in until the suspension was sorted, which needed a bit of thought...
You do not have the required permissions to view the files attached to this post.
Last edited by Guy Rixon on Mon Mar 23, 2015 9:50 pm, edited 1 time in total.

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Mon Mar 23, 2015 9:23 pm

The kit is old-school below solebars with no suspension at all, not even rocking axleguards. Supplied axleguards are castings which are in limbo until I decide whether the springs and axleboxes are worth saving. This is fine by me; I'd rather choose suspension parts to my preferred spec than be stuck with a bad design.

I fitted Bedford sprung axleguards from the "1907 RCH" etch. Nuff said about these elsewhere...except I hate having to fit the springs and wheels with the axleguards in the vehicle, so I did some work to make the axleguards into a removable chassis.

First thing was to get the two axleguards set up square to the correct wheelbase. I folded up the transverse flanges (which I normally leave flat) and broached out their central holes to take a 0.8mm wire. In with the wheels (cheap ones for now, Gibsons, I may fit Exactoscale wheels later) and onto a Brassmasters axle-spacing jig.

IMG_1128.jpg


The jig and the wire fix the alignment and soldering the wire to the axleguard flanges keeps it. Gratifyingly easy!

A check of the chassis between the solebars showed a lovely fit with ~1/2 Rizla working clearance. It also showed that I need about 1.5mm packing to get the buffer height right. And the thing sat level first time, which was a nice extra.

Total time for this stage was only about 20 minutes (net of searching frantically for where I'd stowed the box of wheels).
You do not have the required permissions to view the files attached to this post.
Last edited by Guy Rixon on Mon Mar 23, 2015 9:51 pm, edited 1 time in total.

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Mon Mar 23, 2015 9:48 pm

To make the rolling chassis removable, I broached out the small holes in the horizontal bit of each axleguard etch to pass a 12BA stud. The studs are fitted to the body and the chassis is secured by nuts underneath. I find this easier to do than fixing captive nuts to the body and securing with machine screws. In any case, one set of fastenings is under the verandah floor where there isn't room for the tails of the screws.

The kit doesn't have a wall-to-wall floor. It only has wide flanges along each side, so I needed to make bearers for the studs. I used ~5mm x 0.5mm brass strip (Eileens). I don't think etching-thickness strip would be strong enough. I marked the centres of the holes directly through the axleguards, then pilot drilled to 0.8mm and opened out to 1.3mm. "Official" clearance diameter is 1.4mm for 12BA, but that's a bit sloppy for these studs.

IMG_1135.jpg


The "studs" are actually cheesehead machine-screws and they retain their screw heads for extra strength. For the bearer at the verandah end, I filed down the heads to save space under the floor. At the closed end there was no need for this.

To fit the bearers, I put the chassis into the body and then dropped in the bearers from above, so that the axleguard "bridges" and the bearers sandwich and clamp the flanges.

IMG_1139.jpg


It was then easy to solder the bearers to the top of the flanges without getting the axleguards soldered to the bottom. You can see from the photo that the bearers are slightly skew to the body. This is because I didn't bother to get the holes in the the bearers exactly in the middle. The axleguards themselves are square to the body and the kit has some half-ected alignment marks under the flanges for checking this.

It took about 2.5 hours for this stage, but I think I could do it more quickly on a second vehicle now that I have the technique.
You do not have the required permissions to view the files attached to this post.

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Mon Mar 30, 2015 9:20 am

Most recently, the brakes. The AA7 has clasp brakes - they were through-piped when built and vacuum braked later.

The kit has a separate part for each hangar and shoe and these locate into slots in the flange under the body. That would be fine but (a) I think the slots are spaced laterally for OO and (b) having built a removable chassis it can't be taken on or off when the brake bows are in place. So I mounted the brakes onto the chassis.

I folded over some strip (fret waste) about 2mm wide and clamped one brake hangar into the close end by squeezing shut the bend. I soldered this and them set the opposing hangar. This one I clamped with self-grip tweezers and I set the spacing between the shoes from one of the wheels. I guess one could set the brakes up with a fine gap between the shoes and the wheel, but I didn't bother here: I set the shoes to just touch the outside of the wheel flange giving ample clearance.

I mounted the brake assemblies against the spring-attachment brackets of the BB axleguards. This puts the brakes at about the right lateral spaceing, close enough that they can be tweaked in by bending the base of the hangar.

aa7-brakes-3.jpg


I put the brake-shoe overlays on after the brakes were in place. The brake bows would normally locate into the holes in the brake shoes, but the ones in the kit were a bit short - probably sized for OO again. I put in 0.5mm wire to bace the brake shoes and soldered the brake bows to that.

aa7-brakes-1.jpg


The strip I'd used to hold the brake shoes was bit wider for one end of the wagon. I found, luckily before completing that end, that the wheel treads were hitting the strip when the suspension was near full travel, so I ground out some clearance with a stone in a mini-drill. This would have been very hard to do after the brake bows were in.

I think if I do this brake arrangement again, I will drill the double strip and the hangars and make actual pivots for the hangars. Then I can put the strips in before mounting the hangars, and I can set the shoe-wheel clearance accurately.
You do not have the required permissions to view the files attached to this post.

User avatar
steve howe
Posts: 911
Joined: Sun Feb 01, 2009 10:16 pm

Re: GWR AA7 toad

Postby steve howe » Mon Mar 30, 2015 7:33 pm

What a clear and useful article Guy, techniques that could I'm sure be transferred to other similar etched vans. Do you happen to know if these Toads ran anywhere else on the GWR?

Steve

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Tue Mar 31, 2015 9:32 am

Thanks Steve. As far as I know, there were only 12 of these AA7 vans and they were all in the London area. I don't know how many were needed specifically for the Smithfield trips. I imagine a van at each end of the train, hence the need for short vans and through brake-pipes, but I have no hard information.

Looking at the plan of Smithfield depot, in http://www.londonreconnections.com/2012/london-terminals-fullsome-farringdon-part-1/, I can't see that more than one GWR train could be shunting there at a time. Allowing for two more trains being handled at the other end of the trip (Acton?), that's only 6 toads maximum. Therefore, I presume that the rest were used on trains elsewhere in the London area. On my fictional railway, they get used on the trips to Bedford Street depot, near Covent Garden.

User avatar
Noel
Posts: 1975
Joined: Wed Jun 23, 2010 1:04 pm

Re: GWR AA7 toad

Postby Noel » Tue Mar 31, 2015 10:25 am

Pre-grouping, various freight transfers were worked over the Met, for example GNR to/from SECR. I don't know whether the GW operated such transfers [to London Docks, possibly?], but, if they did, could that be the reason for the number of AA7?

Noel
Regards
Noel

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Tue Mar 31, 2015 11:05 am

Noel, that's an interesting idea. Topologically, there's no reason why GWR-SECR transfers shouldn't come through Holborn Viaduct LL. However, I've never seen any photos showing such trains, so I think the GWR-SECR traffic actually went round the West London to Battersea.

Googling a bit, I found a mention on the Basilica Fields blog of 16 trains per day each way to Smithfield, throughout the day but avoiding the peaks in the passenger workings; this from the 1912 WTT. I stick to my guess that only one train would be at Smithfield at a time.

I had a thought about why the AA7 vans were short. I now think it's a wheelbase limitation. It looks to me like all trains into and out of Smithfield had to be shunted over wagon turntables, including the brake vans. Therefore, the long vans such as AA3 would be a problem. This could apply at other urban depots. Conversely, there was a AA21 (long) van allocated to Action-Smithfield trips in the 1960s (http://www.gwr.org.uk/notes/brakeallocations.doc). Maybe the track layout had been changed by then?

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Tue May 26, 2015 9:40 pm

The AA7 project having been visited by the four horseman of the modelling Apocalypse (work, illness, other projects and family holidays), progress has been slow. I did find time to add the footboards. This starts with soldering supports, made from 0.5mm brass wire, to the etched footboards in a jig made from plywood scraps.

toad-footboards-1.jpg


The footboards were glued temporarily to the jig and prised off after soldering. I used UHU clear glue to for this. It's perfect for this job - and for nothing permanent involving brass - as it grabs strongly at first but later gets bored and lets go easily. After removal from the jig, the supports were cut down the centre with end cutters.

The supports need two successive bends of 90 degrees to form a Z shape. The tails of the Z go horizontally into holes etched in the solebars and are soldered behind the latter.

The first bends, just behind the up-stand of the footboard, I made by gripping the main part of the footboard in my hold-and-fold tool and bending with the wires braced against the bench. This got the bend nice and tight behind the footboard.

The second bend is tricky because it's easy to get the wrong length of wire between the two bends and even a small error hurts. If I bend the supports individually and get different lengths by ~0.25mm they won't locate into the solebar accuracy. If I bend them all at once, with bending bars, then they are the same length, but I can't easily control that length and the steps are likely to end up at the wrong height by 0.5mm or more. In the end, I made a jig consisting of a stack of strip wood topped with a scrap of brass sheet, the whole being the height from the bottom of the wire under the footboard to the bottom of the wire where it goes into the solebars. I could then put the footboard on the bench, put the jig behind the footboard and bend the supports over individually. The first time I tried this (previous project, years ago) the bending forces crunched the wire into the wood and lost the accuracy. This time round, the brass topping on the jig resisted that. These bends came out spot on for height, but I managed to get the angles a bit off in the horizontal pane. The wire is just about soft enough to fix this by twisting and the support tails were thus slightly spring into their sockets.

It now looks like this.

toad-footboards-3.jpg


(Yes, the footboards are too far down the axleguards. That's because the axleguards aren't yet packed out from the vehicle floor. Panic over.)

The footboard supports are neat enough for my standards and vastly stronger than the etched variety. I shall use this approach again.
You do not have the required permissions to view the files attached to this post.

User avatar
David B
Posts: 1509
Joined: Sun Jul 20, 2008 5:30 pm

Re: GWR AA7 toad

Postby David B » Wed May 27, 2015 7:14 am

This is coming on nicely, Guy.

I made one of these some time ago and used Bill Bedford's handrail jig to make the footstep supports. I fixed the ends in to the solebar holes first. When all was soldered on, I tapered the ends of the supports under the footboards to make them less conspicuous. It was a quick job with a small grinding disc in the Dremel.

I have used the same system on other models with footboards including my DD4 Cordon (4th picture, post 27).

David

User avatar
Paul Willis
Forum Team
Posts: 3033
Joined: Sun Jul 20, 2008 6:00 pm

Re: GWR AA7 toad

Postby Paul Willis » Thu May 28, 2015 5:26 am

Guy Rixon wrote:The AA7 project having been visited by the four horseman of the modelling Apocalypse (work, illness, other projects and family holidays),


That is the best quote about railway modelling that I have read for a very long time!

Cheers :-)
Flymo
Beware of Trains - occasional modelling in progress!
www.5522models.co.uk

User avatar
Paul Townsend
Posts: 964
Joined: Mon Sep 14, 2009 6:09 pm

Re: GWR AA7 toad

Postby Paul Townsend » Thu May 28, 2015 8:35 am

Flymo748 wrote:
Guy Rixon wrote:The AA7 project having been visited by the four horseman of the modelling Apocalypse (work, illness, other projects and family holidays),


That is the best quote about railway modelling that I have read for a very long time!

Cheers :-)
Flymo

Here is a 5th horseman relevant to this thread!

I liked the kit as seen here so asked Mr Connoisseur at York show if there is any chance of re-introducing it. He said no plans to do so but if enough requests come in he could be asked again in a year or so

Phil O
Posts: 363
Joined: Sun May 05, 2013 5:23 pm

Re: GWR AA7 toad

Postby Phil O » Fri May 29, 2015 7:40 am

Paul Townsend wrote:
Flymo748 wrote:
Guy Rixon wrote:The AA7 project having been visited by the four horseman of the modelling Apocalypse (work, illness, other projects and family holidays),


That is the best quote about railway modelling that I have read for a very long time!

Cheers :-)
Flymo

Here is a 5th horseman relevant to this thread!

I liked the kit as seen here so asked Mr Connoisseur at York show if there is any chance of re-introducing it. He said no plans to do so but if enough requests come in he could be asked again in a year or so


Paul

Do you have contact details for Mr Connoisseur, I will then add my name to the list.

Thanks

Phil

User avatar
Paul Townsend
Posts: 964
Joined: Mon Sep 14, 2009 6:09 pm

Re: GWR AA7 toad

Postby Paul Townsend » Fri May 29, 2015 10:27 am

Phil O wrote:
Do you have contact details for Mr Connoisseur, I will then add my name to the list.

Thanks

Phil


http://www.jimmcgeown.com/With%20Enquir ... ntact.html

You need to see Jim at a show or snailmail or phone.
Mention the conversation I had at York, he is sympathetic but busy.
AFAIK he doesn't run an organised wish list so this will be an ad hoc attempt to encourage him!
Our Paul Willis pulled it off with his tram which is lovely :)

Phil O
Posts: 363
Joined: Sun May 05, 2013 5:23 pm

Re: GWR AA7 toad

Postby Phil O » Sat May 30, 2015 6:30 am

Paul Townsend wrote:
Phil O wrote:
Do you have contact details for Mr Connoisseur, I will then add my name to the list.

Thanks

Phil


http://www.jimmcgeown.com/With%20Enquir ... ntact.html

You need to see Jim at a show or snailmail or phone.
Mention the conversation I had at York, he is sympathetic but busy.
AFAIK he doesn't run an organised wish list so this will be an ad hoc attempt to encourage him!
Our Paul Willis pulled it off with his tram which is lovely :)


Paul

Many Thanks

Phil

User avatar
Russ Elliott
Posts: 930
Joined: Thu Jun 02, 2011 6:38 pm

Re: GWR AA7 toad

Postby Russ Elliott » Tue Aug 30, 2016 12:32 pm

A belated 'nice' from me, Guy.

It is possible an AA7 or so was used occasionally for a transfer trip to Willesden or Feltham or somewhere like that, but as far as I know, all the AA7s were allocated for exclusive Acton - Smithfield use. I don't think they ever 'top and tailed' the trains though, because all up trains were reversed into Smithfield from Aldersgate, and space at Smithfield depot was at a premium.

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Thu Sep 26, 2019 6:34 pm

The Toad finally got finished, or as near as.
IMG_5707.jpg

Having decided to represent the parts of the body stanchions parallel to the body, I'd bottled out of actually making these parts for years. In the end, I did them from plastic strip with rivet decals and it was very easy. I can see the shadow at the edge of each T-iron in good light, so I feel that it was worth it.

The axleboxes and springs included in the kit seemed over-scale and were cast in with axleguards, so I did not use them. The springs on this model are RFM prints and the axleboxes are (I think) by MJT.

It needs weathering, and I have a ModelU figure to paint up for the guard.
You do not have the required permissions to view the files attached to this post.

User avatar
Craig Warton
Posts: 204
Joined: Sun Jul 20, 2008 7:58 pm

Re: GWR AA7 toad

Postby Craig Warton » Thu Sep 26, 2019 9:46 pm

That looks very good Guy and nice to see someone else gradually finishing long term projects off!

Out of curiosity, for the period you are modelling (Pre WW1?) have you seen photos showing the handrails painted white? It is one of those things I have looked at from time to time and I had formed an impression this came in later.

Regards,

Craig

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Fri Sep 27, 2019 8:01 am

For the AA7s, there are no early photos at all, so it's tricky. The livery on this van is an extrapolation from a later style. Dunno about the handrails, I can't work it out from the information I have. On GWR Toads generally, I see white rails where there are large initials, but there may well be missing examples of van painted immediately after the large initials were begun. Therefore, they are white on the model because it looks nice and I will paint then grey if anybody has clearer information.

User avatar
Noel
Posts: 1975
Joined: Wed Jun 23, 2010 1:04 pm

Re: GWR AA7 toad

Postby Noel » Fri Sep 27, 2019 10:45 am

The first edition of GWR Goods Wagons has photos of new goods brake vans dated 1890 [handrails in body colour] and 1919 [handrails in white]. It also has photographs of new wagons built 1913 and 1915 with brake levers entirely in body colour [bear with me] and of one converted from a carriage in 1917 with white DC brake handles. My suggestion is that the painting of GBV handrails and of DC brake levers [and the handles of longer levers] is related, and occurred at some time during WW1.

A blackout was applied from 1914, because of Zeppelin raids, but the railways were allowed significant relaxations of the rules, because it was deemed necessary to minimise disruption to traffic. However, these rules became much more restrictive from April 1917 https://blog.railwaymuseum.org.uk/raid-on-the-railways/, which seems to me, therefore, to be the most likely time for the application of white paint to start. As a war emergency measure, it could be dealt with locally [any wagon repairer, or even local staff, could apply a coat of white paint] which would minimise the time that the vehicle was out of service, but, even so, it would still take a while for all vehicles in use to be dealt with. Railway works, of course, could start the practice immediately.
Regards
Noel

User avatar
Guy Rixon
Posts: 909
Joined: Sun Mar 27, 2011 6:40 pm

Re: GWR AA7 toad

Postby Guy Rixon » Fri Sep 27, 2019 4:51 pm

Thanks Noel, that's a reasonable assessment and I'll darken my handrails in due course.

More immediately, I need to fix the roof being on the wrong way round and put the chimney is over the cabin.

User avatar
Noel
Posts: 1975
Joined: Wed Jun 23, 2010 1:04 pm

Re: GWR AA7 toad

Postby Noel » Fri Sep 27, 2019 7:46 pm

Side lamp irons?
Regards
Noel


Return to “Guy Rixon”

Who is online

Users browsing this forum: ClaudeBot and 0 guests