Building an MTK 4-DD Double Decker

[Bristol_Rich]

Not sure if you’ve seen this or helps answer the question...

 

 

[grahame]

An impressive project to tackle and a very interesting and unique subject. I recall once seeing one of the two units approaching London Bridge but from another train. 

 

Good luck with progress on your model build. I'll watch with interest. I'd like to have one in N gauge. Maybe one day . . . 

 

[CloggyDog]

10 hours ago, 74009 said:

Hi all,

 

Time for a question.

 

On the data panel painted on the end of the units it says 9' 3" - presumably though this would include grab rails, which are excluded from the dimension on the diagram and could easily account for 1 1/2" each side.

 

 

 

 

Hi Stuart,

 

most of the various references I've seen state there were no commode handles (grab rails) on the 4DDs, One of the issues with the sets was the higher than average number of incidents relating to the omission of both commode handles and footboards under the passenger compartments. Only the cab doors had grab rails.

 

Studying various pics, I'd say the 9'3" overall width was over the door handles/cab-door grabrails, with the width over body being 9'

 

The blood&custard 4DD pages say 9' width "at waist level" but also refer to the very slight taper up to cantrail level.

[74009]

On 06/08/2020 at 06:41, Bristol_Rich said:

Not sure if you’ve seen this or helps answer the question...

 

 

 

 

Thanks Bristol_Rich, that's a great film!

 

All the best

 

Stuart

[74009]

On 06/08/2020 at 06:57, grahame said:

An impressive project to tackle and a very interesting and unique subject. I recall once seeing one of the two units approaching London Bridge but from another train. 

 

Good luck with progress on your model build. I'll watch with interest. I'd like to have one in N gauge. Maybe one day . . . 

 

 

Thanks Graham.

 

The project is paused at the moment until I finish the Clacton Units - not too far to go with those now.

 

All the best

 

Stuart

[74009]

On 06/08/2020 at 08:27, CloggyDog said:

 

Hi Stuart,

 

most of the various references I've seen state there were no commode handles (grab rails) on the 4DDs, One of the issues with the sets was the higher than average number of incidents relating to the omission of both commode handles and footboards under the passenger compartments. Only the cab doors had grab rails.

 

Studying various pics, I'd say the 9'3" overall width was over the door handles/cab-door grabrails, with the width over body being 9'

 

The blood&custard 4DD pages say 9' width "at waist level" but also refer to the very slight taper up to cantrail level.

 

Thanks CloggyDog.

 

I'd never actually noticed the absence of commode handles - so there was a real danger that I would have fitted them in blissful ignorance. Thanks for pointing it out!

 

Yes I think I'm going to go with 9' 0" at the waist.  The picture above from Bristol_Rich does seem to show the taper quite well.  If you hold a pencil vertically against the screen, carefully aligned with the outer edge of either cab window, it's evident how the other side of the pencil is not parallel with the bodyside.  It's a very tiny taper though - in 4mm scale probably no more than ¾mm either side.

 

All the best,

 

Stuart

Edited August 8, 2020 by 74009

[74009]

Sorry for the lack of updates on this.  The 309s took much longer to finish than anticipated, and when I got there I was still considering some questions on the 4DD - so I started an MTK 4EPB (Bulleid) and also a class 207 which are both nearly done.

 

I've decided on having the cab and inner ends for the DD etched; the drawings for this are in preparation now, so hopefully I'll be able to restart it within the next few weeks

 

Stuart 

Edited September 1, 2021 by 74009
Spelling

[74009]

Hi all,

 

So, it's been just over a year since I last looked at the 4DD.  In that time though I've produced an MJT VEP, 2 class 309s, an NNK 2-EPB, an MTK 4-EPB, an MTK Class 207 and I've re-built a 40-year old MTK 4-CEP, so I've been reasonably productive

 

I decided on a final shape for the 4DD vehicle ends based on a very useful and clear photograph taken square on to the end, with almost no skew or perspective distortion.  One of my friends used this to produce a drawing for an etch, which includes cab ends, inner ends, bulkheads and frames for the cab windows and headcode panel.

 

 

 

Edited April 20, 2022 by 74009

[74009]

The shape is a pretty good match to what I guesstimated when I was panel-beating the sides - only two are done though so my current challenge is to get all 8 to match.

 

Edited April 20, 2022 by 74009

[74009]

So, having got sidetracked with some other projects I'm finally back to the 4DD project, and there's been some progress.  I soldered up one of the trailer coach bodies and it actually went together quite nicely.

[74009]

The end is slightly inset because I've got a thinner piece to us as an overlay which has the vertical ribs etched onto it.  This will cover up my untidy soldering and if I use epoxy resin I'll have time to make sure that all the corners are nice and neat.

[Enterprisingwestern]

 it's been just over a year since I last looked at the 4DD.  In that time though I've produced an MJT VEP, 2 class 309s, an NNK 2-EPB, an MTK 4-EPB, an MTK Class 207 and I've re-built a 40-year old MTK 4-CEP, so I've been reasonably productive

 

I shudder to think what your output would be if you got a wiggle on!

 

Mike.

 

[74009]

Because of all the forming and hammering that's gone on, the top edges of the sides aren't entirely straight.  To help with this I clamped and soldered an H shaped brass beam along the whole length.  As well as adding strength there are two other benefits in doing this; firstly, I can cut a strip of plasticard of the correct width to slot into the sides of the H so that it forms a natural arch - this will be fairly strong and once it's in place I can glue it in and use it as a base to build up the roof on.  The H strip can be clearly seen on the middle vehicle in the picture.

 

The other side of the H will be above the upper deck windows so I can locate the glazing strip in this and put some kind of long bar below the lower deck windows to stand the bottom of the glazing strip on.  By cutting the glazing strip to the correct size, it will clip in between the two locating bars and this will press it tightly around the curve inside, giving a flush glazed appearance to the curved upper windows without the glazing always trying to pop off and straighten out.  

Edited January 3, 2023 by 74009

[74009]

13 hours ago, Enterprisingwestern said:

 it's been just over a year since I last looked at the 4DD.  In that time though I've produced an MJT VEP, 2 class 309s, an NNK 2-EPB, an MTK 4-EPB, an MTK Class 207 and I've re-built a 40-year old MTK 4-CEP, so I've been reasonably productive

 

I shudder to think what your output would be if you got a wiggle on!

 

Mike.

 

 

Thanks Mike.

 

Many years ago I was offered a job as a full time modelmaker by a shop that I used to do the occasional commission for.  At the time it wasn't the right thing for me and I also thought that if I was going to do that, it might be something to do independently rather than for an employer.  Maybe it'll be something to fall back on if I get made redundant, as I do tend to get things done quite quickly and doing it full time would increase output further.  As well as what's listed above I've also made good progress with models of the prototype HST 252001, an S.R. 'Z' class and a Craftsman Models class 119 DMU.   I'll put a thread up soon about the HST.

 

Stuart

Edited April 20, 2022 by 74009

[74009]

This is the current state of play, with the cab fronts fitted and  frames added around the opening cab window and the headcode.  I quite liked the way that MTK dealt with the inset guard's doors - very easy to form and fit.  I'm considering now how I'm going to motorise this as it's pretty heavy - I'm hoping to be able to use a Replica motorised chassis if I can get one to fit.

[74009]

Hi all,

A long overdue return to the 4DD.  I had set it to one side temporarily, awaiting inspiration, because I was struggling with the roof sections - I'd tried curving brass to the right diameter and also made some attempts with plastikard but all methods failed.  A couple of other projects therefore came in between (a class 119 DMU, now finished, and a prototype HST 252001 - this is not finished, but I'm past all the difficult bits and I'll put a thread up about that soon).

 

Recently I was rummaging through a drawer of assorted bits and pieces looking for something to use as a floor and I came across some thin pressed aluminium roof sections.  They were in a box of things I'd been given by an elderly friend when he'd decommissioned his model railway a couple of years back - they were quite pliable and I wondered whether they might solve my 4DD problems.

I carefully marked a couple out and cut them from end to end, retaining only the central section, then shaped them to match the profile of the DD.  Once in place I secured them with rubber bands and then poured a puddle of epoxy resin inside which has completely sealed up everything, roof, sides and ends.   They have actually fitted pretty well - a couple of gaps to fill and sand, but the whole structure is nice and rigid now so I'll do the same with the centre cars.

I've also fitted a Replica Railways powered chassis into one of the centre cars, which you can see in the middle picture.  For this particular application the workings of it are actually a tiny bit high and are visible through the lower deck windows, but I'm going to see if I can get away with it with some compartment walls and seats shaped to fit over it. If that's not possible I can easily remove it and find another motorisation method.

I'm challenging myself to get this finished by the end of February, as I want to enter it in a competition on 28th.

Edited January 9, 2023 by 74009

[John Tomlinson]

39 minutes ago, 74009 said:

Hi all,

A long overdue return to the 4DD.  I had set it to one side temporarily, awaiting inspiration, because I was struggling with the roof sections - I'd tried curving brass to the right diameter and also made some attempts with plastikard but all methods failed.  A couple of other projects therefore came in between (a class 119 DMU, now finished, and a prototype HST 252001 - this is not finished, but I'm past all the difficult bits and I'll put a thread up about that next soon).

 

Recently I was rummaging through a drawer of assorted bits and pieces looking for something to use as a floor and I came across some thin pressed aluminium roof sections.  They were in a box of things I'd been given by an elderly friend when he'd decommissioned his model railway a couple of years back - they were quite pliable and I wondered whether they might solve my 4DD problems.

I carefully marked a couple out and cut them from end to end, retaining only the central section, then shaped them to match the profile of the DD.  Once in place I secured them with rubber bands and then poured a puddle of epoxy resin inside which has completely sealed up everything, roof, sides and ends.   They have actually fitted pretty well - a couple of gaps to fill and sand, but the whole structure is nice and rigid now so I'll do the same with the centre cars.

I've also fitted a Replica Railways powered chassis into one of the centre cars, which you can see in the middle picture.  For this particular application the workings of it are actually a tiny bit high and are visible through the lower deck windows, but I'm going to see if I can get away with it with some compartment walls and seats shaped to fit over it. If that's not possible I can easily remove it and find another motorisation method.

I'm challenging myself to get this finished by the end of February, as I want to enter it in a competition on 28th.

 

Really looking the business now, and a textbook case of waiting for inspiration/ the right answer, rather than jumping in and making a  mess!

 

John.

[74009]

After what seems like a whole weekend of filling, filing and sanding, the fit of the roofing is now like this.   I think that's about as good as I'm going to get it, although it will be much easier to see if there are any major issues once a coat of primer has been applied.

I started drilling out for the door handles but, with the brass being so hard and thick, I snapped 3 drills and achieved a total of 2 holes.  More drills, of a couple of different types, on order; fortunately the number of doors isn't huge.  I'll also fit all the roof detail before priming - drilling here will be much easier as the aluminium is very soft - plus the holes will be bigger.

 

 

Edited January 16, 2023 by 74009

[Enterprisingwestern]

 

Are the door handles already a hole or just spotted?, if the former try opening out with a broach, if the latter then which type of pin vice and whose drills are you using?

 

Mike.

[Darius43]

With MTK brass sides I had the same problem of breaking fine drill bits.  I solved it by using a large sewing needle in a pin vice to first mark and slightly open out the hole - like a miniature awl.  The drill bit then has something to purchase and is less prone to breaking.

 

When using the “awl” you need to support the rear surface of the brass to avoid making a dent.

 

Cheers

 

Darius

Edited January 16, 2023 by Darius43

[74009]

Hi Mike / Darius,

In this case the hole positions are not marked at all so it's just a case of drilling through the full thickness (and it's particularly thick!) brass.  When the new drills arrive I'm thinking about preparing by supporting the back of the etch on an anvil or something then tapping it firmly from the front with a hammer on a sharp object to create a divot to work from.  

I can't remember where the drill bits came from - they were just 'in a box'.   The new ones I've ordered are a mixture of steel and tungsten carbide, and some have the 3mm shank.

 

Best regards

 

Stuart

[Enterprisingwestern]

 

As Darius says, pressing the needle, (make sure it is steel so it doesn't bend when you push, in my case I use a fine pointed scriber), should be sufficient to make enough of an indent without having to resort to hammering.

Also, don't use Chinese monkey metal drills, I find a lot have no point on the end and are little more than glorified nails, and a quality pin vice with the chuck slots cut concentrically to avoid any wobble is de rigueur.

 

Mike.

[74009]

Hi all,

 

It's a long, long time since I posted an update on this - progress has been very slow for an assortment of reasons, but I'm hoping to get back to it in earnest soon - maybe I can beat KR Models!  Below is a link to a short video of the unit on test, at the Chatham and district Model Railway Club.

 

Stuart

 

https://www.flickr.com/photos/74009/53570214438/in/dateposted-public/