LNER A6

[mikemeg]

The GW mini roller came out again, this time to roll the cab roof. I've found that with a little practice (and I probably need more) it is possible to roll curves from around 16 - 18 mm diameter (this for very small boilers) up to the radii needed for cab roofs; in this case 8' 8" (35mm). The resulting cab roof is curved much more evenly than if bent up by hand. The ribs were then soldered to the underside of the rolled roof.

 

When I first looked at this arrangement, it appeared that this wouldn't work because the cab rear locker was in the way. Having identified this, I duly reported it, only to find that Arthur had thought of this and had made provision for the roof rib to pass between the locker and the cab rear by leaving an appropriately sized gap at the top of the locker. He thinks of everything - well pretty near everything!

 

I also assembled the inverted 'T' strap which was added to tie the tanks together, though I haven't fixed it yet. This is another of those really lovely bits of etching and goes together surprisingly easily. The Isinglass drawing mentions and shows this in connection with the 63B and 63C boilers (superheated) but does not mention it, or show it, for the 61 boiler (saturated). However photographs of 69798, which retained its saturated 61 boiler until withdrawal in 1951, do show this 'T' strap fitted.

 

So with the cab roof done all of the major platework is now done, with the exception of the footplate steps. Still a real joy to build, even without a full set of instructions.

 

Looking out of the window, we may have our second consecutive day without rain, in which case my excuse for not having cut the lawns is rendered invalid and the modelling, for today, could well be interrupted by needing to charge up and down with me lawnmower. I've always wanted a sit-on lawn mower - well for a good few years, I have - though I haven't yet acquired one; I'm still using the old petrol driven job. Does about thirty lawns to the gallon, if I don't drive it too aggressively!

 

Cheers

 

Mike

[Horsetan]

.....thirty lawns to the gallon....

 

[mikemeg]

After a very productive day in the garden, yesterday, when the lawns were cut and various trimming, weeding and planting jobs were done, today the sky is overcast and rain looks imminent, so perhaps a good day at the models.

 

I've done a few more 'adjustments' to the A6; the jointing ring between the boiler and smokebox has been slightly packed out from the rear smokebox former to be a little more prominent, the front frames on the A6 have been slightly sanded to improve the fit with the smokebox wrapper and with the footplate and both cab roofs have been adjusted to improve the fit at the eaves.

 

Lots of little adjusting jobs, with not a lot to show but if they're not done now, then the final model will certainly display the fact that they should have been done. I think it's one of those things which improves with practice; seeing those tiny one, two or even five thousandths of an inch discrepancies and recitfying them. After all, there's only so much that paint will fill and better if it doesn't have to. It's also an intensely personal thing this level of acceptance, of tolerance of not quite fitting. For me, digital photography and the ability to magnify these pictures, to an almost ridiculous extent, is crucial in achieving the required standard, though I guess I am never ever fully satisfied and always feel it could be better.

 

So onward with these two locos.

 

Cheers

 

Mike

[Paul Cram]

What did you use for the sandbox operating rods? Was it an etched piece in the kit?

[mikemeg]

What did you use for the sandbox operating rods? Was it an etched piece in the kit?

 

Paul,

 

Yes, the sandbox operating rods are etched pieces in the kits. They are etched very finely and need to be bent up at the sandbox end. Also etched are the supporting brackets at the rear of the splashers. I fitted these rods by drilling the splasher out to 1/32" and then letting into each splasher a tiny length of 1/32 tube, the end 1.0 mm of which had been turned down to around 0.6 mm; just turned down using a needle file with the tube held in a pin chuck.

 

Each piece of tube was then soldered into the splasher and filed down so that only around 0.5 mm, of the turned down tube, protruded. Then a length of 0.4 mm wire was let into the top of this tube, onto which was slotted the end of the sandbox rod. A touch of solder and then the wire can be filed down to the top of the rod. The supporting brackets were attached to the rods using small pieces of 0.3 mm wire, again soldered and then filed down.

 

All of this sounds fiddly but, under a reasonable magnifying glass on a stand, this wasn't difficult to do. The resulting assemblies do look very authentic, particularly as Arthur etched these rods to scale width.

 

Regards

 

Mike

[Paul Cram]

Thanks for that reply. How big is scale width?

[ArthurK]

Thanks for that reply. How big is scale width?

 

Not sure if it is exact scale but they are 0.66mm which is 2" in proper units!

 

ArthurK

[mikemeg]

So I am now on the final lap of building the J73 body. The footplate steps have all been assembled and fitted. One thing I did do, here, was to add the flare at the end of each of the steps; this by scoring the step 0.75 mm from each edge and then bending the end of the step to produce that characteristic flare. Of course this doesn't have to be done but it does improve the look of the footplate steps.

 

I've also made the support cradle for this body. This stops the weighted loco body resting on the footplate steps and thereby deforming them. Just an open box of .060" plasticard, painted black.

 

Now onto the final body detailing and then on to do the same operations on the A6.

 

Cheers

 

Mike

[Paul Cram]

Not sure if it is exact scale but they are 0.66mm which is 2" in proper units!

 

ArthurK

 

Thanks

[mikemeg]

Just about there on the A6 body, until the castings arrive. I still have to do the front lamp irons and the valve cover but these will be done tonight, along with the lifting eyes in the front frames.

 

The rainstrips, on the cab roof, were made using 0.5 mm wire which was filed down slightly on both sides. This is simply done by putting a 90 degree bend in the wire, leaving around 10 mm, which then indicates which side is being filed - I normally do both sides. Once this is done, the wire is cut to size and formed into the curve of the rainstrip - there are half etched marks which show the extent of this curvature and into which the rainstrip can be soldered. A final clean up with the glass fibre brush and all is well.

 

Cheers

 

Mike

[Worsdell forever]

Thought it was about time I commented on this, they're turning into superb models Mike, it seems Arthur really is a master kit designer...

Can't wait to get one of the A6's myself and have a go, my second loco kit was the Little Engines kit for one and it would have built up into a good model if it wasn't for my inexperience.

Keep up the good work.

[mikemeg]

Thought it was about time I commented on this, they're turning into superb models Mike, it seems Arthur really is a master kit designer...

Can't wait to get one of the A6's myself and have a go, my second loco kit was the Little Engines kit for one and it would have built up into a good model if it wasn't for my inexperience.

Keep up the good work.

 

Arthur is, indeed, a master kit designer but then he has been doing it for quite a while. Amazing thing is, among many amazing things, that Arthur uses his own graphics software to draw and design these kits.

 

I too bought one of the Little Engines A6 kits but used only the boiler and castings; the rest was scratch built; but you really can't compare that kit with Arthur's etched kit; there is a world of difference. You'll certainly enjoy building the A6 as I am. Now for the chassis' for the A6 and J73.

 

Regards

 

Mike

[ArthurK]

Mike is doing a great job on this by noting all the problems he encountered. Tabs wrong on the upper frames, no slots for the for the front lamp irons plus a number of other little things. One omission that he has found is the absence of steps under the rear buffer beam. That's something else that I will have to correct. The locos in their 4-6-0 guise didn't have them but they appear to have been added when they were rebuilt. Cetainlty photos taken in the NER period show these. The other "big" tanks of the NER had similar steps. Another omission more easily corrected is the vertical handrails behind the bunker on each side. Again the 4-6-0 version did not have these.

 

I am never fully happy until I have personally put a set of etches together. I know how it is intended to be built but Mike has had the very minimum of intructions, an exploded isometric and very little else. I am following up Mike's build with one of my own and not surprisingly came across the same problems. So far mine has reached the stage of basic footplate, tanks and boiler assembly. I have just received castings for the tank fillers (the masters were made by a good friend of mine) and thought that it would be a good idea to pose one of these on my build. I looks pretty good although the hinge is a bit too prominant but a few strokes with a file will fix that. Below are two photos of the result. It is just sitting there - no solder yet!

 

 

 

ArthurK

[mikemeg]

Arthur,

 

Those tank fillers do look very nice. Am I correct in thinking that these tank fillers are appropriate for any of the ex-NER tank locomotives or are they specific to the A6? If more generally applicable, then which of your kits are they appropriate to.

 

As regards building the A6, from a minimum of instructions, just a real joy. I guess having made an A6, earlier from scratch, has helped in building this one and is a good check on the dimensions of my earlier build, though I fancy any differences in dimensions between the two are down to me.

 

One thing I have found with building these models fairly intensively, is that many of the techniques and processes, which I have previously had problems with, are now becoming very much more straightforward. Words of the great Jack Nicklaus again, when he was asked why he was so lucky in winning Golf Majors :-

 

'You know the more I practice, the luckier I get.' he said.

 

It's true! The more I practice the easier this becomes; though it's not yet a doddle and I doubt it ever will be.

 

Cheers

 

Mike

[ArthurK]

Mike

 

The tank fillers are suitable for most if not all of the NER tank locos with minor exceptions. For some unknown reason the fillers on the J73 were placed further back on the tank top. As a result the latch could not be hinged from the tank front but was instead hinged from the tank top. It means that the latch on the castings will have to be cut back to tank top level but I doubt if anything apart from a close inspection will reveal the fact that there is not actually a hinge there.

 

I will send two with the castings for your A6. The backhead fittings are not complete I still need the drivers Dreadnought vacuum brake control. Also there are no vacuum or train heating pipes though I do have a sprue with them on.

 

ArthurK

[mikemeg]

So on to the chassis for the A6. The chassis, on all of Arthur's kits can either be built rigid or can be sprung or compensated, using compensation beams, sprung hornblocks or continuous springy beams. To cater for these two alternative approaches, two sets of coupling rods are provided; one set rigid the other set formed in two parts with provision for articulation at the rod knuckle, as per the prototype.

 

As I intend to use springing or compensation (still to decide, though the driving axle, which will be the front axle, will be left rigid) then the first thing to assemble is the coupling rods, which will then form the datum set for the assembly of the hornblocks into the frames and for the subsequent assembly of the chassis in the assembly jig.

 

All of the rods have been parted from the etch, tabs cleaned up and then the two halves of each rod soldered up, taking care not to introduce any solder into the fork of the two forked rods. For the articulation, I normally drill the two parts of the knuckle to 0.75 mm - provides a much greater bearing surface for this articulation. I then make up steel pins from steel panel pins, just turned down in a pin chuck, leaving a 1.0 mm shoulder which will sit at the front of the rod. The pin is then soldered to the rear of the forked rod and filed flush to prevent any binding.

 

If the chassis is being built rigid, then the solid rods can be used and are designed to line up precisely with the axle drilling in the mainframes.

 

Cheers

 

Mike

[Horsetan]

....If the chassis is being built rigid, then the solid rods can be used and are designed to line up precisely with the axle drilling in the mainframes.

 

Solid rods are also useful to check and set hornblock positions using your favoured jigs - you can do it all in one hit.

[mikemeg]

Solid rods are also useful to check and set hornblock positions using your favoured jigs - you can do it all in one hit.

 

Yea, verily, Horsetan, I could indeed, if I hadn't used the solid rods for my scratchbuilt A6. Oh the P4 adherents will wince at that - building a P4 loco with a solid chassis, but then I believe Guy Williams (who knew a thing or two about model loco building) didn't always (ever?) use any form of springing or compensation. And the scratchbuilt A6 does have a sprung trailing axle, with pick ups on it. Mind you, I wouldn't do that if I were starting the scratchbuild now!

 

Thanks and regards

 

Mike

[Mike G]

Oh the P4 adherents will wince at that - building a P4 loco with a solid chassis, but then I believe Guy Williams (who knew a thing or two about model loco building) didn't always (ever?) use any form of springing or compensation

Thanks and regards

 

I always think that a solid chassis needs good trackwork to perform on. I'm no PM expert by any means, which is why I use compo and or springing. I do wonder sometimes why we get so hung up on adhering to dogmas passed down. If it works, it works. Is there a more compelling argument than that?

 

Really enjoying the build.

 

Mike

[ArthurK]

Must admit my intention was to drive my A6 on the centre axle but that does lead to problems if that axle is fixed (which I would prefer). Driving on the front (or the rear?) means that the two other axles can be easily compensated or sprung. The compensation would require a rocking hinge to ensure 'three point' suspension. Must take a re-look at my drawings and decide on the best way (for me) to go.

 

ArthurK

[ArthurK]

Just had a quick look at the drawing. Using the first axle to drive on looks attractive. The motor/gearbox is Mashima 1420 driving through Highlevel Roadrunner. The angle is not critical and there is plenty of room for a flywheel. I think that mounting the rear axles on a CSB would be ideal.

 

Plenty of room for weight in this one so the springing might have to be fairly stiff.

 

 

ArthurK

[mikemeg]

Must admit my intention was to drive my A6 on the centre axle but that does lead to problems if that axle is fixed (which I would prefer). Driving on the front (or the rear?) means that the two other axles can be easily compensated or sprung. The compensation would require a rocking hinge to ensure 'three point' suspension. Must take a re-look at my drawings and decide on the best way (for me) to go.

 

ArthurK

 

It is perfectly possible to drive the A6 on the centre axle, though that does somewhat restrict the choice of motor and its mounting options if the motor is not to impinge on the backhead. I chose to use the front axle so that I could accommodate a Mashima 1620 and Comet 50 : 1 two stage gearbox, which has a grub screwed final drive gear wheel. This is the drive configuration on my scratch built A6 and that is looking like a prodigious haulier in initial trials, even with a rigid chassis. This combination will just go in, without cropping off one end of the motor shaft and there is probably enough room to fit a flywheel if the motor is mounted with the free end lowered slightly from the horzontal.

 

If this is so (driven on the front axle) and if that axle is fixed, which is my preferred option to avoid all those torque twisting problems on a 'floating' motor and gearbox (and yes I know that some of the CLAG members have devised solutions to this problem), then that makes the compensation option a little more difficult, so I shall almost certainly use CSB's on the middle and rear driving wheel sets.

 

In essence, this will then be sprung like a 2-4-0. I think I am correct in saying that Jazz (he of 7mm loco building renown on this topic area) uses fixed driving axles wherever possible.

 

Cheers

 

Mike

[mikemeg]

On now to the mainframes. As per the prototype, the mainframes on this kit have sections which are 'bolted on' at the rear. These mainframe extensions were actually 3 inches closer together than the original mainframes on the prototype locomotives, after rebuilding to 4-6-2's. Arthur's kit follows this practice with mainframe extensions which are spaced inside the mainframes with a small piece carrying the brake gear operating brackets. These various sections are designed to be lined up using etched holes for 0.5 mm wire; there are seven such positions for the wire so squareness should be easily achieved.

 

One feature of these locomotives and many other ex-NER locos was a row of bolts on the mainframes where the cylinder block casting was held in place. On the A6, there are actually two such rows of bolts. On previous kits Arthur has half etched these, allowing them to be pressed through, though doing that does produce a large rivet rather than a bolt. On this kit Arthur has etched these holes fully, so that small pieces of 0.5 mm wire can be soldered in and then dressed off to around 0.5 mm proud of the mainframe to more accurately represent these bolts. This sounds like a very fiddly job but it can be done relatively easily and quickly, as long as each piece is soldered in quickly with just a wipe. If the iron is allowed to 'dwell' then those already in place will fall out.

 

So the cutting out, fettling, cutting of the two sprung hornguides, adding the thirteen pieces of 0.5 mm wire for the bolts and assembling the mainframe extensions took around an hour and a quarter.

 

The coupling rods have now been articulated and checked for free movement. I hope this loco is never going to travel over trackwork which will require the degree of movement in the photograph!

 

Cheers

 

Mike

[billbedford]

Can some one tell me what is the point of fixing just one axle? The body will follow the fixed axle any track imperfection and result in very unprototypical running. Putting CSB on just two axles is just a waste of effort you will get better running if all the axle were fixed, though better still would be to put CSBs on all the axles and use a floating gearbox and carden drive from the motor.

[mikemeg]

Can some one tell me what is the point of fixing just one axle? The body will follow the fixed axle any track imperfection and result in very unprototypical running. Putting CSB on just two axles is just a waste of effort you will get better running if all the axle were fixed, though better still would be to put CSBs on all the axles and use a floating gearbox and carden drive from the motor.

 

Now I think I might just try that! I must confess that my dislike of floating gearbox/motor combinations was based on experience with the Q5/2 kit, where the motor's torque tended to rotate the motor/gearbox. That said, a motor/gearbox fitted to a fixed driving axle, will also attempt to rotate if there is any binding, even slight binding, on the motion or if the gears are not correctly meshed and properly run in.

 

There you go, Bill, thanks for the comment.

 

Cheers

 

Mike