Martin Finney 7mm A3

Richard Spoors

Western Thunderer
Hi Peter, very nice indeed. I have checked my V2 coned boiler and firebox work again and soldered the firebox wrapper which fits perfectly with the rear of the wrapper overhanging very slightly as the instructions say it should. I have a nice smooth join between both wrappers above the footplate which makes me believe that my angles are correct. Yet I still have this annoying 1mm gap at the bottom flange of the coned boiler where it meets the firebox former. The V2 instructions don't mention a cusp, but that the coned boiler former should be soldered "almost flush with the ends of the wrapper ...." which I have done. Before soldering the boiler and firebox sections I'm going to build my cab and check it's fit with the firebox.
Cheers

Richard
 

P A D

Western Thunderer
Coming along nicely now :thumbs:

The couplings are a by product of the legacy kit and associated art work I'm afraid. Whilst they remain on the etch work we are duty bound to keep them in the instructions as some people may still use them. If the art work gets revamped or upgraded then we will remove the etched couplings at that point; all new kits being currently designed are not planned to have etched couplings provided.

The smoke box saddle is down to the mould, one mould does both ends, however if the mould was adjusted so each end was the same length (to remove the extra 5mm, by reducing each by 2.5mm) then the resultant joint would not be fully hidden by the steam pipe covers, the joint would effectively move rearward by 2.5mm. This is one of the downsides to modelling an engine with offset steam pipe covers in relation to the smoke box saddle.

As part of our ongoing assessment of the legacy kits, this is one area we feel can be improved with a new one piece casting, which if successful, will be included in future releases.

An A4 too :eek:, nice choice and makes a very nice engine at the end. The A3 and A4 are very much alike under the hood so all the A3 work will stand you in good stead. Just shout out if you need any info on engines and tenders etc, more than happy to assist.

MD

Hi Mick,
My first thought was why the castings were not made 2.5 mm shorter. Then the penny dropped with regard to the offset steam pipes and hiding the joint. Cutting it down is quite straight forward and it made a change to have to do some fettling again.

I couldn't resist the A4 after seeing the W1 and tender at Kettering. Not the same of course but it got the juices going.

As you mention, the under pinnings will be very similar to the A3, so that will be useful. I've ordered it with the corridor tender and the hornblocks to give the compensation a go, so a bit of a change there.

Thanks for the offer of prototype info if I need it. I have a Dave Ennis designed A4 built some years back, so should have enough refference works, but I'll shout if I need anything.

Cheers,
Peter
 

P A D

Western Thunderer
So back to the build.

I know it's a bit risky, but the running plate/ valance jig was annoying me and it has served its main purpose, so I decided to cut it off. First though, I drilled the running plate under the fire box and also drilled and tapped 10BA corresponding holes in the fire box baseplate. This allowed me to screw the fire box and running plate together at the rear. At the front I drilled through the chassis mounting hole into the smoke box and tapped the hole 6BA. This is a temporary quick fix until I sort out an alternative fixing. Here is an underside view after most of the excess solder and crud that I could not get to with the jig in place, has been cleaned. It needs more attention particularly the splasher joints but I'll get back to that later.
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The holes in front of the slots in the footplate are for the 10 BA bolts.
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The temporary fixing hole in the smoke box. With the joining strip inside there is just enough metal to tap it. 20180314_190443.jpg

And screwed together.
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The running plate fire box joint is pretty good but I think a little bit of panel beating underneath should close the slight gap under the mud hole.
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T'other side may also benefit from a tap or two. The foot plate is only placed for the photos.
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To improve the appearance of the bogie I have replaced the cheese head bolts with counter sunk ones, so they are less visible.
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Should be just about invisible under there when painted.
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I'll have to knock up a simple wooden plinth for the running plate, to avoid damage when adding the details on top.

Cheers,
Peter
 

Richard Spoors

Western Thunderer
Hi Richard,
Can you post a picture showing the gap.
Cheers,
Peter

Peter, the firebox and boiler are pinned and clamped ready to be soldered together. You will see my gap problem which I have closed by shaping, soldering and carefully filing a piece of scrap. The upper join between the boiler wrappers I'm happy with. I could have closed my V2 boiler firebox 3.JPG V2 boiler firebox 4.JPG gap by changing the angle of the firebox former, but had I done this I could not have fitted the firebox wrapper correctly.
When I have made up my cab it will be interesting to see if I have a problem when I put all the superstructures on the footplate. I shan't solder everything together until I can check this.
Cheers

Richard
 

P A D

Western Thunderer
Peter, the firebox and boiler are pinned and clamped ready to be soldered together. You will see my gap problem which I have closed by shaping, soldering and carefully filing a piece of scrap. The upper join between the boiler wrappers I'm happy with. I could have closed my View attachment 85385 View attachment 85386 gap by changing the angle of the firebox former, but had I done this I could not have fitted the firebox wrapper correctly.
When I have made up my cab it will be interesting to see if I have a problem when I put all the superstructures on the footplate. I shan't solder everything together until I can check this.
Cheers

Richard

Hi Richard,
I see what you mean now. Your fix looks good on its own, but it's bit of a concern that if something is out of line, it will impact on the fit of the cab. I hope it is all OK.

Have you got the running plate formed yet, and if so how is the fit of the firebox?

Cheers,
Peter
 

Richard Spoors

Western Thunderer
Hi Peter, I'm happy with the fit of my cab and firebox on the footplate. All very snug and tidy. My next check will be when I have finished the footplate details at the front end with the smokebox support. Will not be for a couple of weeks as I'm taking a short break.

You might be finished by then?

Cheers

Richard
 

P A D

Western Thunderer
Hi Richard,
Good to hear it worked out OK.

I have now drilled and tapped some holes under the smoke box to fix the front end to the running plate.

First I soldered a strip of thick NS inside the smoke box over the the temporary 6BA tapped hole. 2 holes were then drilled in the running plate cross member to take 10 BA bolts. I then drilled through these holes into the smoke box and the NS strip, and then tapped them 10BA. The holes in the cross member were then widened to clear the 10 BA bolts, and finally a 6BA nut for fixing the chassis was soldered to the top of the cross member between the two smaller holes.
I've not decided whether the cast saddle will be attached to the smoke box or running plate, as that will depend on where plumbing needs to be fixed.
20180315_193445.jpg

The cheese head bolts under the fire box were fouling the top edge of the frames so I repositioned them and swapped to counter sunk. I added another at the back of the firebox for good measure.
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I made a start on the cab. Here are the main parts, with the floor partly assembled. The 6BA nuts are for retaining the chassis, to the running plate and the 10 BA for retaining the rear of cab. The cab front plate will be bolted to the back of the fire box
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All bolted together.
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And with the right hand cab side blue tacked in place. Looking good.
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Cheers,
Peter
 
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P A D

Western Thunderer
The main cab structure is now completed and screws nicely to the running plate and fire box. Here is the cab and roof which is designed slot in place. I'll probably glue it after painting. Like the running plate it is built up on a sacrificial jig which is removed with a cutting disc when completed.
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Here's the cab with the roof in place. There are optional etches for the ventilator, either both open as shown, or one open and one closed.
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And screwed to the running plate. 20180319_215144.jpg

And on the chassis with the tender. The chimney and dome are just placed for the photo.
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Definitely looking like an A3 now. And yes I know the smoke box saddle is back to front, and the trailing wheel is not on the track. The saddle is not fixed yet so no problem.
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Cheers,
Peter
 

P A D

Western Thunderer
As I had folded up the cylinder etch I thought I'd continue with it. First you have to laminate the six etchings that make up the slide bars. Here they are still pinned to a piece of wood after soldering. The pins keep them all aligned and are the cut off and filed back. The short extension on the right is later cut off to allow the cross head to fit between the slide bars.
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Here they are after a good deal of fettling with the cross heads added.
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And with the cylinder frame. There are rectangular slots in the front and rear plates to locate the forward extensions on the slide bars.
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And after fitting to the rear cylinder plate.
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And with the valve guides added. The ones at the front are shorter, which I did not realise at first, but spotted the difference before I soldered them in place. I know some builders don't like the multiple etch slide bars, but I think they are a really good design and very simple to locate accurately. They are more time consuming but I'm just building for pleasure and not to a deadline.20180321_200138.jpg

And fitted to the frames 20180321_192502.jpg

And with the body in place. 20180321_192406.jpg
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And finally the cab with the seats and cast floor parts epoxied in place. I have soldered a NS base from waste etch to the back plate, and drilled and tapped a hole 10 BA, so that it may be bolted to the footplate.
20180320_183411.jpg

Cheers,
Peter
 

P A D

Western Thunderer
Some further work in the fire box area with the fitting of the footsteps on the slope of running plate. I also took the opportunity to improve the fit of the running plate/fire box joint, with some judicious panel beating with a jeweller's hammer on the underside, to remove the very slight gap.
20180322_210644.jpg

If you look back at some of the previous photos of this area you will notice the improvement.
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And then back to the frames with the fitting of the remaining spacer at the front, which incorporates the footsteps.
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Then I went back to the cylinders and added the covers and front and rear relief valves.
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And back on the frames. From the notes posted elsewhere on here by Mickoo, the gap on the right frame at the front for the passage of the 2:1 lever will need reducing as it is too large.20180322_210931.jpg

And with the body on.20180322_211044.jpg

And a full length view of t'other side. Getting there.
20180322_211233.jpg

Cheers,
Peter
 

P A D

Western Thunderer
I've now added the slide bar bracket and motion bracket. This shows the motion bracket slotted into the frames. There is no stretcher joining this to the slide bar bracket, so I decided to add something from waste fret to link them.
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As the brackets are at different levels I used two corner pieces from one of the NS frets. Here they are before soldering. The vertical (shorter) sections were cut back to length after fitting.
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And in the frames with the body on.
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And the other side.
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Time to make a start on the valve gear.

Cheers,
Peter​
 

adrian

Flying Squad
I've now added the slide bar bracket and motion bracket. This shows the motion bracket slotted into the frames. There is no stretcher joining this to the slide bar bracket, so I decided to add something from waste fret to link them.
Nice work as always - although I'm curious why does the motion bracket need connecting to the slide bar bracket?
 

P A D

Western Thunderer
Hi Adrian,
I want the cylinders and valve gear to be de-mountable as a unit. As far as I can tell from reading the instructions, the only thing linking the motion bracket to the cylinders is the actual valve gear. This way it's rigid when taken out, and now I can build the valve gear off the chassis, which I believe is easier than doing it in-situe.

The stretchers run close to the frames on either side and will hide some of the half etch dimples visible through the gap between boiler and running plate
Cheers,
Peter
 

P A D

Western Thunderer
Here is the left side stretcher.
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Next the connecting rods. The instructions suggest pinning them to the cross head with NS rod, but I went for tapping the outer hole 10 BA and securing with a counter sunk bolt from the inside.
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The crank pins were then altered from 12 BA bolts to 10 BA, and the bushes tapped out to fit. Here are a rear and front ones after modification. The rear one on the left has a JLTRT cast nut, and the front has the brass bush reversed for extra clearance.
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And a middle driver. The width required to clear the coupling and connecting rod big end, just matches two Slaters bushes with room for a spacing washer. The return crank has been soldered to
the outer bush.
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And with the wheels back in the chassis and the rods fitted.
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And the other side.
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The balance weight have now been stuck to the wheels with super glue.
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And the chimney and dome epoxied to the smokebox and boiler.
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The front buffers are very nice white metal castings, with dual action as explained by this shot of the assembly diagram.
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I like the 14 BA nut fitting, which would have been good to have on the rear buffers instead of the 8 BA. This would have made it possible to fit the buffers at the correct width.

And on the buffer beam.
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Next the 2:1 levers. Here they are ready for fitting.
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And in place. The instructions suggest using NS rod for the main pivot, but I opted to tap the hole in the fixing beam 10 BA, and fix with a bolt. The valve rods will need trimming to accommdate the rear valve rods and it will be easier to do if the 2:1 set up can be taken off.
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And a parting shot with the smoke box door blue tacked in place. I'll be adding a slug of lead later so it can't be fitted permanently yet.
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Cheers,
Peter
 

Tom Insole

Western Thunderer
I’m also really enjoying watching this fine engine come together. Just stunning!
Lovely depth of detail too which is nice to read :D
 
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