7mm MOK Ivatt 4MT in S7

Discussion in 'Area 51' started by richard carr, 16 January 2016.

  1. richard carr

    richard carr Western Thunderer

    This was one of my Christmas presents from Emma. I have always fancied building an MOK kit and this seemed like a good starting point, a chance to practice on something before the 9f comes out. There is something about these engines, even if it's that they are just ugly. I also felt it was time to get back to building something that requires solder !

    Now a few may be thinking what am I doing building a kettle, shouldn't it be a blue diesel, well like steam engines too, especially those of the north east and particularly those that worked on the Stainmore line, so this one is going to be 43055, which was shedded at Kirkby Stephen in 1955 and ended its days at North Blyth in 1966 and never really left the north eastern region.

    I'm going to start with the tender and take it from there, following the extensive instructions closely.

    It starts with the tender chassis frame spacers, here are a few of them made up

    View attachment 51513

    Here are the frames with one of the spacers attached with the tabs

    View attachment 51511

    The kit makes extensive use of tabs and slots, these aren't just a lose fit, these have so far all fitted perfectly together, the parts can only go in one position

    The tender chassis uses a 3 point compensation system, (although it looks a bit 4 point to me). These are the rocking beams.


    And here's the chassis put together



    The front 2 bearings are fixed and the other 2 on each side can move up and down about 1.5 mm and rock from side to side a s a unit of 4 by about 1 mm.

    I'm sure it will work just fine.
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  2. daifly

    daifly Western Thunderer

    I'm looking forward to following this build. Sadly for me a a GW/WR aficionado, none of the 76xxx 4MT class were ever allocated to the WR but, bizarrely, all three mishaps to locos of the class listed on Wiki occurred on the Didcot, Newbury and Southampton line - in WR territory!


    Oops. Correction below!
    Last edited: 16 January 2016
  3. Scale7JB

    Scale7JB Western Thunderer

    Definitely need more STEAM engines..!

    John Miller and Wagonman like this.
  4. Mr Grumpy

    Mr Grumpy Western Thunderer

    I have pulled up my chair and settled down to watch this beautiful kit being built.
    I couldn't drag myself away from Dave's stand at Reading. Outstanding is too small a word to use to describe his kits!
    Don't keep us waiting!!!!
  5. richard carr

    richard carr Western Thunderer

    OK I better get on with it then.

    The first 2 photos don't seem to have loaded so here they are.



    Everything so far has fitted together beautifully, the next bit is to make up the axle boxes, there are 8 castings for each one, but again they all fit together perfectly

    Here are the castings on the sprue


    And here they are after about an hours cleaning up.

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  6. warren haywood

    warren haywood Western Thunderer

    Dave, I think this ones a 43xxx,
  7. daifly

    daifly Western Thunderer

    Sorry. Got taken in by the '4MT' description when I looked at the MOK kit list. Thanks for the correction.
  8. markjj

    markjj Western Thunderer

    I'm looking forward to this build I have just recently placed an order for 2 while I'm waiting for my 9f kits to appear.
    What tender are you building ?
  9. markjj

    markjj Western Thunderer

    I think I have fallen into the same pit lol I'm doing 2 76000's with BR2 tenders
    I'm awfully tempted to get an Ivatt as well they sure are beautiful kits.....
    TommyM likes this.
  10. richard carr

    richard carr Western Thunderer

    I made a bit more progress yesterday.

    Here is the underside of the body with the 2 main tender outer frames. Folding up the supports for the cross beam is tricky as there isnt much metal to bend on the rear one in particular so its very easy to twist that when you don't want to. You then need to solder on a thickening piece that requires a careful bit of soldering to get it exactly in in the right place, so you can tap the holes 14 ba.



    There is an overlay for the frames, again the tab and slot system locates in exactly the right place.


    And now I have assembled the axle box castings and added them to one of the frames. These do look good once they are finished.
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  11. Mr Grumpy

    Mr Grumpy Western Thunderer

    Hope this isn't a daft question, is the folding of the supports made more difficult due to the changes made to the kit to be S7 friendly?

  12. richard carr

    richard carr Western Thunderer

    No, its because there isn't a great deal of metal to get hold of on either side of the fold, so when you make the fold it tends to twist the entire bit of metal on the frame.

    So far I haven't made any changes to the kit to make this an S7 loco and I don't think I will either need to, or it won't be practical to.

    For example, it won't be practical to widen the loco frames, if I did I would need to adjust all the castings that attach to the frames and there are quite a few, and some would be pretty difficult to do. That's why Dave did a separate version of the standard 4MT tank, where he widened the frames and made separate castings for S7.

    It won't be a problem with the 9f as it has narrow frames anyway, so even for finescale they will be the correct scale width.
    Compton castle likes this.
  13. richard carr

    richard carr Western Thunderer

    Some more progress has been made, a hour here and an hour there to get to here.


    It has all gone together remarkably quickly, I have only spent about 12 hours on it all so far.

    Everything has fit together perfectly , the instructions say if you need to remove the cusped edge or not and generally you don't.

    I have made one small change to the kit by removing a piece of the coal bunker so that I can access the water tank.


    Here you can see the inside of the tender body, its all just held together by the tabs, I'm going about battery power to this loco with the Tam Valley DRS system and batteries and all the electronic gubbins are going to go in the tender, so I have cut out a large part of the coal plate so that the batteries can fit in the water tank.


    Here is the tender insides all soldered up with one of my favourite holding tools


    Its a few bits of wooden point work sleeper glued together with super glue but it makes holding the nickle silver bits so much easier, a double layer keeps your fingers well away from the metal and flux.
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  14. Mr Grumpy

    Mr Grumpy Western Thunderer

    Hi Richard,
    Looking good.
    What method do you use to remove the
  15. Scale7JB

    Scale7JB Western Thunderer

    That's pretty impressive progress..!

  16. dibateg

    dibateg Western Thunderer

    Because everything fits, they go together quite quickly, such a joy to build. I've just started my 3rd MOK Ivatt, but at the other end. I'm looking forward to seeing more.

  17. richard carr

    richard carr Western Thunderer

    Tony's right, the build time is very fast as everything just fits first time with no messing about filing a bit of here and bit off there.


    I found your thread on building the pair of Ivatts, its going to be very useful once I get onto the loco body.

  18. richard carr

    richard carr Western Thunderer


    I just cut them off with a pair of Xuron cutters and then get a big file out and remove whats left, then a quick finish with a nice file to leave things perfectly smooth. It only takes a couple of minutes to do.

  19. richard carr

    richard carr Western Thunderer

    Here's some more photos of how I got this far.


    This is the first stage of the upper part of the tender cab


    This is the tender front with all the detail added, all those hinge overlays, I did mange to solder the larger ones on but the small ones are glued and it looks like one has fallen off, there are plenty of spares in the kit though.


    And this is most of what has been done so far.

    Adding the tender skin did seem like a daunting task, but folding it proved much easier than I expected, there is a bend gauge for the sides and the rear part to help you get it right. There is for once a fair bit of work to get the skin to match the tender end overlay and the cab front, but it does tell you this in detail in the instructions.


    Here the tender skin is just held in place by the tabs.
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  20. Genghis

    Genghis Western Thunderer

    I have one of these lurking in a cupboard so will watch this with interest.