Steve Beattie kit NBL Class 21 build

Now to fix the body proper I started at the cab ends at gutter line level, this is a small run of solder from the gutter downwards towards the centre of the upper bodyside angle, the sides on the Class 21 have a double profile angle sloping inwards and soldering at this point will pull the sides in against the skeleton.

Next set a full line of solder along the roof formers noting that the roof profile sits down correctly over the three formers.

Then starting with the middle bulkheads solder down the sides ensuring the bodyshell is pulled tight against the bulkhead and that the side profile angles look correct, also check that the side girders of the mainframe are sitting level with the skeleton base piece, if they are not then by adding gentle pressure onto the bodyshell in the middle before soldering the middle bulkhead will see the bodyshell sit down correctly. I will add that because this is not so easy to get the iron tip in it doesn't matter if the solder is a bit sloppy, in fact solder over-spill will assist in the strength of the bodyshell.

Now when the girder ends are sitting flat to the skeleton base plate the lower section of the body sides can be soldered to the bulkheads.

And the loco body is placed on the flat stone slab to check that the sides are straight, a bit like when you buy a vintage car you look along the swage line to spot any kinks and dips.

 

Now the botton edge of the bodyshell needs to be soldered to the skeleton, I tack soldered along this edge in a few places just to hold the body then removed the mainframe to get proper access when soldering. The tack solder spots will also stop the body warping and bulging when soldering along this line.

Then I put the bodyshell back on the flat stone to check for straighness, if the body shows a slight rocking motion it is at this point that it can gently be twisted back into alignment. The bottom of the bodyshell sits nicely on the flat stone on both sides with no daylight showing.

Finally the whole bottom edge can be seam soldered to complete the integrity of the bodyshell strength, again solder overspill will make the framework stronger.

Now at this point I will add that the bodyshell has full strength, the monocoque nature of this construction makes the bodyshell quite solid and completely reliable for handling without issue when the loco is completed.

 

The cab sides are hugely delicate at this stage, one interesting aspect is that this area doesn't bend at the weak point behind the cab doors but instead after soldering the weak point becomes the area of the window surrounds.

 

Thanks Toto, happy to know you like the build... this kit is very forgiving to build and maybe the thinner etches work to this advantage, having said that the bodyshell etch is folded from quite a thick section of brass.

 

Not thought of that one Toto... I'll make a set of cardboard "gloves" to protect this area, now I've got the roof panels cleaned up and have dozens of rivets the emboss then I can sweat these onto the roof and get on with the side louvers and grills... that's this weekends job.

 

Thanks Toto... no drama with these kits at all... I never felt the need to become a national attention seeker nor have I ever wanted to climb Welsh mountains

 

So a little bit of research regarding the roof panels was in order this morning because I am now at the stage where I can dress the bodyshell with the various vents covers and panels. The kit instructions suggest that to rivet emboss these panels would be incorrect and all NBL roof panels were not riveted, and to show the way NBL built these locos here is a picture depicting how the roof panel edging was formed, also the side strips above and below side wall grills show good detail as well. Picture by Tom Curtis of this loco in Barry scrapyard, an interesting point to note is how the paint patch and number is being weathered away with the salt air to expose another number becoming evident behind it. Now the theory is this loco is not D6122 but is actually D6121 as identities were swapped at Inverurie Works because the real D6122 had sustained some sort of damage whilst in storage and was quietly cut up to avoid a scandal, also because of the incredibly short working lives of these machines as Class 21's it would seem doubtful if they received a repaint which the Barry photo evidence suggests a patch number overpainting.

I have some 1mm phosphor bronze strip which I can glue to the edges once the roof panels have been fitted, however I doubt I'll go to the effort of rivet punching all the way along the body sidewall strips.

 

I read that a chap took the remaining part of the original NBL builders plate off this loco and the works number cast into the diamond plate was the one allocated to D6121.

 

Further photographic evidence shows the real D6122 had the cab front "eyebrow" vents in the lower position, this D6122 at Barry shows the eyebrow vents in the upper position above the cab windows which was where D6121 had its eyebrow vents located. Both these engines spent considerable amounts of time stored out of use at Inverurie and the real D6122 had had a lot of money spent on it when it was damaged. So I guess to avoid a press scandal of wasting taxpayers money on new engines that didn't work properly the real 6122 was cut up and the impostor in the shape of 6121 took its place.

 

Cut up before my time... when I saw this engine in Barry as a teenager it was 1974.

 

Agreed, the Class 21 and its Western Hydraulic partner the Class 22 were nice looking late first generation loco's with character, you can see the design shape that was fashionable of those times... the Metro Vicks, Sulzers, Westerns, Southern electro diesels and Deltic shapes. Although Warships were essentially a German design lifted for British use and boxy 47 shapes with angled cab fronts became the house design of the 60's and 70's.