BR Standard Class 4 Loco Build

Before soldering the pivot stud I added the axle bearings dry as an added alignment tool to support the beam during the soldering process.

Finally with the beam pivot soldered and moving freely the paper was removed and the protruding stud end and excess solder on the outside face of the main frame was filed down flush for a clean finish.

I'll do the other frame side tomorrow and then move back to the tender brake rigging.

 

Thanks for that tip Pete, I'll try it ... actually thanks for reminding me I need some blacking liquid and Eileen's sell it and they will be at the Show next week.

 

Thank you for that Gentlemen I really appreciate it, Toto I'm happy to know it's compulsive viewing as I was beginning to feel I was over posting on this thread and I wouldn't want to do that. Paul ... thanks for your kind comment too, I've seen the benchmark set by established model makers and I'm learning from them all the time. I think the thing I'd say about this remade Transport Age kit is that it puts the emphasis of construction firmly with the builder, there are no cd roms or multi photo step by step diagrams to follow you have to go research the subject to understand the finite details. All part of the learning curve tho.

York Paul

 

Ok there Toto, here's a non picture update, whilst looking at the tender brake rigging I realised two options to proceed building are available as the outer wheelsets have around 2mm sideplay within the inner carrier frames... this is a design feature of the kit as the etches have been solder correctly onto the spacer pieces. So to proceed fixing the brake hanger assembly in its correct position I risk electrical shorting out or do I stop and order 5BA brass shim washers as packers to reduce sidway travel, I've opted for the latter as I intend for the brake blocks to have reasonably prototypical spacings against the tyre flanges. I'll post a few pics up later of what I mean. The etches for the tender have Acorn on them so I suspect the design of this kit goes back to a time when very tight curves in O Gauge were generally the order of the day, it will be interesting to compare if this flaw has been eliminated with one of the forthcoming new design Scorpio kits that are to be released later this year.

York Paul

 

As Toto says "saves a lot of potential heartache later and scratching your head wondering where the short is happening" and he is correct of course as what is the point of building something if it doesn't function as you hope it will. So here is the potential issue that has flagged itself up, as we can see an excessive sideways movement of the axle currently occurs which means to avoid an electrical short out the brake hangers need to be positioned so as not to make contact with the wheel flange in its sideways travel, that puts the brake hanger assembly out of phase in realistic spacing with the wheel and also affects the positioning of the cast brass push bars of the rigging and adjusters. This is what I mean about the sideways travel of the wheelset, note also the centre axle has 1mm spacer washers fitted against the sprung hornblocks.

And this is the position I am aiming to achieve which is much more prototypical, the brake hanger located with about 0.5mm clearance of the tyre flange allowing some some lateral movement.

The green paint on my fingers is because I've just spent the last couple hours sprucing up the garden fencing.

 

Now I've soldered one side of the drag box onto the loco main frames, I'm not going to go any further until the jig arrives but I couldn't see that fitting this component would compromise setting the whole frame true. I'm working on the principle that if care is taken in the frame build everything else will follow smoothly too, so this isn't going to be rushed and I'm not impatient, after all what is the point investing time, money and energy if it isn't going to be right in the end. Anyway here is the drag box fitted to one side on the main frame, the compensation beam can be seen also.

 

Now one final aspect whilst I am preparing the main frames for assembly is to check the alignment of the front bogie stretcher plate and to see what needs to be done in order to achieve a square fit, I'm not saying I don't trust the etches but after folding up the lip edges of the bogie carrier plate and offering to the mainframe I noticed daylight on the inner edge inside the notched cut out. The solder stick points to the offending area in question... again please excuse my grubby thumb.

As we can see there is a bit of slack in there which will potentially compromise correct alignment of the bogie. This will not do !

 

So to overcome this I needed to determine the centre line position in order to prove the correct location of the stretcher plate, it is most important to do this before the frames go for assembly as otherwise it will be near impossible to do afterwards and the frames may even sit skewed over the bogie. Remember we have to spring the bogie pivot plate with the underside of the stretcher so the loco sits correctly and we have to ensure there is smooth and free movement of the bogie too. The first stage is to measure the distance across the stretcher plate then mark up and scribe a centre line on the inside face of this plate.

Next I needed to ascertain the centre line position on the main frames, so by placing the mainframes together facing each other that proved both etches were a mirror image, then I scribed lines at the end of the flats where the bogie wheel arc starts on each frame piece, the distance between arcs were 21mm so the centre line marking point is 12.5mm. These marks are made on the inside faces of the frames only.

Finally by placing all marked up pieces together we can show accurate positioning when soldering together, so now all the preparatory work on the frames is complete and the one item that needs to be made will be the lamination of the side rods. This is the point where work on the main frames stop until the jig arrives or I go cap in hand again to Mr Lundie.

 

Thanks Toto, I do hope this thread inspires other folk to get into etch kit building, it is for me a very enjoyable experience.

 

What a great idea that one Paul thanks for the inspiration, the kit suggests using an 8BA bolt as the actual pivot pin and feeding it in through the top of the carrier plate soldered in with a wire would also stop the bolt turning in the event the bogie had to be removed.

 

Rob thanks again for the tip, the masking tape is easily removed afterwards with small turns of the wheelset.