Martin Finney 7mm A3

Discussion in 'Area 51' started by P A D, 19 January 2018.

  1. P A D

    P A D Western Thunderer

    Having recently completed the building of my Gladiator Duchess and with my L1 from the same stable going through the paint shop, my thoughts turned to what to get next. I was leaning towards the Scorpio Std 3 2-6-2 when purely by chance, I came across this unbuilt Martin Finney 7mm A3 plus non corridor tender and a full set of Slaters wheels for a very good price on ebay. Long story short, the Std 3 will have to wait.

    Having said the price was very good, it was still a considerable outlay and therefore a bit of a gamble, although the seller stated that as far as was know it was complete. I have checked all the etchings , castings and other bits and bobs and all is there. There is a slight problem with the Slaters wheels which I was aware of before purchasing, but I'll come to that.

    There was some minor damage to a few of the smaller more delicate parts which I have easily straightened and which will cause no issues in construction. In the main the frets were clean and free of any tarnishing, but a couple of the sheets were badly stained on one side. I'm guessing this was due to an inadequate final rinse after the etching process. I cleaned them up with hob brute and an old tooth brush and then rines well and dried.

    Here are the loco etchings.
    20180115_155210.jpg 20180115_160422.jpg 20180115_160721.jpg 20180115_161009.jpg 20180115_161346.jpg

    And the bits and bobs plus the wheels.

    No problem with the driving wheels, but the leading and trailing wheels are the standard type with 3/16 axles instead of the special Finney variety with 5/32 axles. I was confidant I could use the leading wheels without problem by opening out the holes in the bogie frame to accept larger bushes, but was not sure if that was the case with the trailing wheels. I sent a mail to Richard Lambert who kindly checked his A3 model and confirmed that it would not be possible to use the larger axles and bushes as I s uspected . There was the option of Slaters exchanging them for a small handling charge, but I came up with another solution , which I will come to later.

    Here are the tender etcings .

    There is an extra loose part in this photo which is a duplicate of the coal hole and front panel. This was taped over the corresponding part on the fret but is slightly different in terms of having some extra tabs. I believe this may have been added to correct an error in the original artwork but as yet my scanning of the instructions has not spotted any reference to it.

    As with the leading and trailing wheels, the tender wheels are the 3/16 axle standard Slaters type. They are also spoked wheels not disc. However, I believe I can use these also by widening the slots in the inner tender frame to except the larger diameter axles, and converting them to discs should just be a matter of making some disc inserts.

    My impression from reading other builds on forums and reviews in magazines, is that despite the complexity of Finney kits, if the instructions are followed closely, no problems will be encountered. So bearing that in mind, I went off on a tangent!

    I wanted to settle how I was going to resolve the issue of the axle for the cartazzi slider. Having given it some thought and checked the diameter of the holes for the bushes for the Finney type axles, I decided it was possible to use the wheels that came with the kit. Here's what I settled on.

    There are three sets of frame spacers sizes provided in the kit, large for scale 7, medium for finescale, and a third narrower set. I'm using the middle size ones and the bogie and cartazzi set up have corresponding size spacers.

    First the axle bush holes in the slider were "reamed" slightly to accept the 3/16 axles without brass bushes. Then the slider sides from the scale 7 size were separated from the base and filed to fit inside the sides of the medium one I'm using. These were soldered in place to give more of a bearing surface for the axle, and the the top of the slider solder to the slots in the top of the unit to complete. Here is the medium slider base, top and the large base with the sides separated.

    And lined up in the frame with a spare axle for soldering .

    And the top piece added
    The double thickness sides should provide enough bearing surface for the axle

    Here it is with the wheels in.

    I still have the remaining narrow frame and I will solder them to the outside later to create a larger bearing surface and negate the need for washers. Thanks to Dave Holt for suggesting that.

    With that matter settled, I can get back to following the instructions, starting with the tender inner frames.

    Last edited: 19 January 2018
  2. P A D

    P A D Western Thunderer

    I see I have typed "Martin" twice in the heading. Anybody know if I can edit that?
  3. mickoo

    mickoo Western Thunderer

    An easier way is to simply turn down the 3/16" axles to 5/32" there will be just enough of the shoulder left on the square stub end to locate the wheel. See my A7 build for more info when I did the bogie axles to fit the 5/32" white metal axle box castings.

    Some tender wheels remained spoked on the A3 tenders and some were even mixed up. There was an A3 or A4 kicking around with three disc and one spoked at one time IIRC.

    The tender front etch attached to the main sheet is damaged, it is missing the two tabs for the shovel plate and the two tabs for the screw handles, one for the scoop and one for the handbrake. The supplementary replacement is correct. The tabs could of been broken off in transit to the original owner and Martin has sent a new replacement. I am not aware of any replacement etches, nor is it written in the instructions which have just be revised. I think that may be on line or will be soon, if not get hold of Richard or myself and we'll send a copy by email if you wish. If you prefer a hard copy and are going to Bristol I can print a set off for you to collect.

    Mick D
  4. adrian

    adrian Flying Squad

    For future reference on the first post, top right hand side there are "thread tools" which allow you to edit the title, as it's a simple edit I've done it for this thread - now taking longer to write the reply!
  5. BrushType4

    BrushType4 Western Thunderer

    I shall be following this with interest.
  6. P A D

    P A D Western Thunderer

    Many thanks Adrian.

    Thanks for the comments on the axles, but I don't have access to the equipment to turn them down to 5/32, so to use them I've had to modify the cartazzi frame. Quite simple to do in the end.

    I have now built the tender inner frame and simply widened the axle slots with a 3/16 chainsaw file. I've got the compensation beams and wheels in and all works well and the chassis is level. Again quite simple to do. I'll write that up and post some pictures later.

    Although it's quite a simple set of parts, I'm very impressed with how well they all fitted. It's the best fitting slot and tab arrangement I've ever built so I have high expectations for the rest of the kit.

    I haven't studied the tender front etch, so you may be right that the 4 missing tabs have been broken off. I was pretty sure the loose one was the correct one.

    I doubt if I will be able to get down to the Bristol show but we'll see. If I do I'll come an say hello to you and Richard.

    adrian likes this.
  7. mickoo

    mickoo Western Thunderer


    I was incorrect, it's not the tabs for the screw handles but the two smaller ones for the water valves.

    This is what you should end up with.


    This is the high front end as applicable to A4 / W1 engines but fitted with the low front, later BR, simplified sheet metal coal door .

    Watch the front handrails as well, they should be 4'-3" spacing for the A3 and 4'-6" for the A4 but some A4's had 4'-3" handrails but I don't think any A3's had 4'-6" handrails.

    There's no front turn in or beading to add on this tender so it's the simplest of all the three to form up.

    Tenders on the A3 and A4 class changed like the weather, do you have a date and specific loco in mind? That'll also have an impact on the boiler fitted (washout plug positions, firebox hand rail position, domes, frame holes and reversing lever shape)

  8. Scale7JB

    Scale7JB Western Thunderer

    I was tempted by the eBay listing, but I let it go, you can thank me later ;)

  9. P A D

    P A D Western Thunderer

    Thanks for the further information.

    That tender is what mine looks like in my dreams! If I get half there I'll be pleased.

    No as yet I havn't decided which loco to build. From the various reference books I have, I have been unable to gleem enough information to make a decision. However, I want it to be in BR Green, early logo and single chimney. I need to find the right loco to fit the bill with the tender I have. I ordered a copy of The Book of the A3s which I hope will help me more than the books I currently have.

    I've been reading through your thread on the David Andrews A3 and it's clear that the detail variations within the class are a minefield.

    BrushType4 likes this.
  10. P A D

    P A D Western Thunderer

    Hi JB,
    Yes there were a lot of punters watching it. I could feel the fingers poised over the "buy it now" button as I frantically checked the photos before making a decision. Luckily on the "Building O Gauge On Line" website, Christian Cresswell has posted pictures of all the etchings and parts. I couldn't check the castings etc as they were in the bags, so a bit of a gamble but it turned out OK.

    Another kit saved from the clutches of the Scale 7 mafia!
    Only joking.

    Last edited: 20 January 2018
  11. Dikitriki

    Dikitriki Flying Squad

    Hi Peter,

    One thing you may not have considered..... By the use of standard 3/16" axles instead of 5/32", if you have not amended either the pivot holes of the compensation beams, or the arms of the beams bearing on the axles, the tender will be riding 1/64" high......if it bothers you:)

  12. P A D

    P A D Western Thunderer

    Hi Richard,

    No it doesn't bother me . I think you would need eagle eyes to spot the difference, even stood next to an identical tender which had the 5/32 axles. Also the increased ride height in relation to the loco will in my opinion be insignificant.

    It's a valid point though and thanks for pointing it out.

    By the way has your Duchess been painted yet? Having finished the L1 my intention was to paint my Duchess asap, but then the A3 arrived.

  13. P A D

    P A D Western Thunderer

    So on with the tender.

    Here are the side frames for the inner chassis being prepared. The lower one has had the folds made to the axle slots and the front slot has been widened to 3/16 with a chain saw file.


    Here the upper one has all the slots widened and the keeper plates folded over and soldered. The lower one is ready for the slots to be widened.

    Here's the front end after assembly of the frames and spacers. The front spacer has a gap on the vertical face for the drag beam to pass through. Care is needed when handling as the brass is quite thin and with the gap is prone to being bent.
    And the a view of the whole chassis .
    20180118_190614.jpg 20180118_190644.jpg

    And after addition of the compensation beams. One central at the front and two either side at the rear. The tube mounting for the rear ones it separated in the middle so they can pivot independently.
    20180119_191511.jpg 20180119_191555.jpg

    I added the wheels for a quick check and all is well. There's a bit of side play on the axles even using the widest of the three sets of spacers, which will be taken up with washers.

    Dave Holt over on RMweb suggested adding the sides of the spare cartazzi sliding frame to the assembled slider to increase the bearing surface and negate the need for axle washers. It seemed like a good idea but I decided to modify a 3/16 brass bearing instead. I cut the flanges off a couple of bearings, cleaned up and then added them to the unit instead of the washers. I then carefully tack soldered them to the sides and removed the wheels and axle. After clamping the unit in a machine vice I added more solder and flux to complete the joint. Here it is after cleaning up with the remains of one of the bearings.

    So now there is minimal side play without the need for washers and increased bearing surface.

  14. mickoo

    mickoo Western Thunderer

    Peter, with that tender you're really limited on choices of engines, there was only ten of these tenders and most ended up on the A4s.

    I think the logos changed around 1957 ? and double chimneys arrived between 58-59, so I've made the cut off date as 1957.

    For your period you have a choice of six.
    60046 Diamond Jubilee, tender #5644 (1937 - 1963)
    60058 Blair Athol, tender #5643 (1955 - 1963)
    60062 Minoru, tender #5643 (1953 - 1955)
    60084 Trigo, tender# 5645 (1940 - 1964) the frame holes on this engine as it's from Lot 317
    60095 Flamingo, tender #5637 (1954 - 1961)
    60103 Flying Scotsman, tender #5640 (1938 - 1963)

    Frames are a nightmare and there's very little information out there, other than Lot 317 which were all built with 4 holes the rest are and can be a hotch potch of oval holes, round holes, blanked holes, blanked oval with a round hole in the doubler strengthening plate.

    All the A3 suffered badly from cracked frames especially over the leading driver and consequently most were rebuilt at some point with new frames from just ahead of the rear driver forward. Some of these used Lot 317 frames with round holes, some / most? used Lot 331 with no holes.

    For your period and without a detailed frame photo from that period, your best bet is no holes except the rear most one, to be pedantic it would be a oval hole in the main frame and a doubler strengthening plate fitted behind with a round hole in, but if you're not overly bothered with the doubler plate then just cut out the round hole marked on the etches.

    Boilers are your next issue, the kit will only build the 94A or 94HP, not the 107 without moving the mud hole doors.

    Cross referencing the boilers leaves you with
    60046 94A
    60058 94A
    60062 94HP (51-52), 94A (52-62)
    60084 94HP (54-55), 94A (55 +)
    60103 94A

    The 94HP has the round top hat dome, the 94A and 107 have the large streamlined dome, not Banjo...please! The Banjo dome is much smaller and limited to engines pre war on a small scale.

    Allocation wise,
    60046 Southern ECML
    60058 Northern ECML
    60062 Southern ECML
    60084 Northern ECML
    60103 Southern ECML

    The 'book of' is a good choice, nice clear pictures, but the information is limited to the images they show (a snap shot in time), better books for more details over a longer period are RCTS 2A and Yeadons, the recent (last couple of years) A3 book 'Ninety Years On - Coster- Irwell Press' is also very good.

  15. P A D

    P A D Western Thunderer

    Thats brilliant. You are an absolute Diamond Geezer!

    Thank you very much for sharing that. With all that information you've got me off to a good start and saved me a lot of leg work. It's also good to know your opinion on the refference works available.

    I've got the Yeadon's volume you mention and will also have a search for the RCTS 2A. Incidently, W. Yeadon was born in Yeadon which is only a couple of miles from my home. Small world.

    I need to take in what you have provided and then start scouring refference works so I can decide which one to model.

    What about the rivet pattern on the main frames. I understand they started out flush riveted on the early ones and changed throughout their years in service to snap head. I think the ones build as A3 had snap heads from the start. From what you say I guess it' very difficult to decide which rivets to punch. Any thoughts on that would be much appreciated.

    Thanks again.
  16. oldravendale

    oldravendale Western Thunderer

    Peter, you've achieved more with your build than I have in three years! Well, in truth I have a (coal rail) tender in primer, thanks to Mr Mickoo who's built it for the F7 display. The loco was started but is now stopped while I work on the LBSCR "K". For aficionados of the "K" build, yes, there is stuff going on after a three month hiatus. Updates will follow on the appropriate channel.....

    Peter Cross, 3 LINK, 7mmMick and 2 others like this.
  17. Rob R

    Rob R Western Thunderer

    This may, or may not be helpful.
    Donc 01.jpg
    Robert The Devil 4479 Doncaster 8th May 1937

    Rob (not the devil)
    3 LINK, BrushType4, 7mmMick and 2 others like this.
  18. mickoo

    mickoo Western Thunderer

    It is, as it shows the doubler plate with no hole in it, you can just make out the oval hole in the main frames but the plate behind is solid. The engine was built with four large oval holes (Lot 297), none of the others are visible, and they would be. So this engine has had at some point a whole new set of frames ahead of the intermediate brake bracket.

    Peter, frame rivets are really hard to discern, I've a couple of large quality close ups and they show near smooth rivets for the horn guides and pan heads for some of the rest, which matches the image Rob has posted.


    If you look at the J hanger bottom right, you can see the inner rivet is slightly domed, the outer two (nearer the rim) are flush with an indents in them.

    However the Doncaster frame drawing O-164-N for Lot 314 (four oval holes 60090-60098) and Lot 317 (four round holes 60084-60088, 099-101) is quite implicit in that all marked rivets are countersunk on the outside, and there are a lot of them. Some are marked countersunk flush so I'd expect them to be flat, the others slightly raised but probably not discernible in 7mm scale.

    Last edited: 23 January 2018
  19. Dikitriki

    Dikitriki Flying Squad

    Mick is, indeed a Diamond Geezer with an unbelievable knowledge of all sorts of things.

    Segueing nicely into my own model of Diamond Jubilee, which is awaiting chipping, chassis holes, test running and painting.
    While it's fresh in Mick's memory, what pattern of holes/solid backed holes should I have in the chassis in the (say) mid to late 50s period.
    My resolution this year was to get some of my backlog finished, and this is at the top of the list.

    Peter.....closely followed by the Duchess which needs a bit of piping on the chassis and odd bits of detail on the body, eg the atomiser front left footplate. Did you get any good pics off COB?


  20. P A D

    P A D Western Thunderer

    Thanks again Mick.
    It seem you are font of knowledge when it come to LNER Pacifics. No doubt I'll be asking more questions as the build progresses.

    Thanks also to Rob. (Is that not now a devil or never was a devil?) :)

    I took pot loads of pics of CoB including the cab interior which is fully accessible. The loco is separated from the tender with a platform which makes it look crap, but is good for taking photos of the cab and tender front. There is a gantry along the right hand running plate which prevents taking any detail photos below the running plate. It' a poor place to display a steam loco. About time it was moved to the NRM.

    I also got lucky and found DoS parked up at Crewe and went into a clicking frenzy.
    Of course with this one you have to sift out the post preservation paraphernalia.

    Let me know what you need and I'll put them.