Nick Dunhill's workshop, M&GN 4-4-2T Melton Tanks

Discussion in 'Area 51' started by Nick Dunhill, 28 July 2019.

  1. P A D

    P A D Western Thunderer

    Very nice Nick.

    That's a neat trick with the waste fret soldered over the half etched line. Filed it away for future use.:thumbs:

    Cheers,
    Peter
     
  2. Nick Dunhill

    Nick Dunhill Western Thunderer

    ....massive leap today, or so it seems. Actually all the preparation was done towards the end of last week. I did a lot of measuring up , and you can see that I have soldered some small lengths of scrap onto the footplate as a location guide for the sides. Remember the footplate and body sides have no tabs and slots. The cab front, rear and floor were attached, and then the other side. Finally the bunker floor and rear panel and beading. I have added tapered handrails to the cab side, and steps to the tank front.


    [​IMG]


    [​IMG]


    [​IMG]


    [​IMG]


    [​IMG]


    [​IMG]


    Next I will (catch the other loco up) add some more cab detail, build a cab roof and close up the insides of the water tanks. Then it's just the boiler to go.......
     
  3. Nick Dunhill

    Nick Dunhill Western Thunderer

    .......next I added all the angle iron bits of strapping round the various parts of the cab, and cut out a paper roof template.


    [​IMG]


    [​IMG]


    I continued with the theme of strapping and angle onto the underside of the cab roof, and they formed a good way of locating the roof on the cap top.


    [​IMG]


    [​IMG]


    Next, more cab stuff........
     
    BR Tony, David B, Deano747 and 11 others like this.
  4. P A D

    P A D Western Thunderer

    Hi Nick,
    Fantastic build as always. Is that a slot above the cab front and rear lookouts that the glazing will drop into? It looks like the front and rear plates are 3 piece laminates, but with a gap where the lookouts are.

    Cheers,
    Peter
     
  5. Nick Dunhill

    Nick Dunhill Western Thunderer

    Ey up Peter. The cab front and rear are 2 laminates with half etched slots for glazing.
     
    michl080 likes this.
  6. P A D

    P A D Western Thunderer

    Clever stuff. Guarantees a perfect fit of the glazing with no risk of glue on the "glass". We need more kits with features like that.
     
    michl080 likes this.
  7. mickoo

    mickoo Western Thunderer

    I'm going to steal some credit here, the Finney7 W1 was the development engine for this form of glazing, not only the front spectacle plates but also the sliding cab side window units, it was fine tuned on the 'in progress' B1 and applied to this set of etches for Nicks M&GN A class it was also on the additional side glazing units on his recent NGG16 he asked me to whizz up.

    The W1 was different in that there isn't two walls to trap the glazing, there was an outer wall and an etched window frame surround on the inside, the glazing still dropped in from the top, but had to be cut to roughly the same shape as the window frame.

    The Finney7 NER A7 will be revised to include this format.

    It'll be standard on all of my future designs, as already noted, no need to cut glazing to exact sizes or fiddly glue in jobs, just drop in the slot after paint and retain with the cab roof. I'm sure it's not a new idea or a wheel re-invention, though I've not seen it before; I simply got tired of fiddling around with traditional methods.
     
    BR Tony, David B, Deano747 and 11 others like this.
  8. Nick Dunhill

    Nick Dunhill Western Thunderer

    I have fitted out the cab. Planking on the floor (sorry WH, customer preference) handbrake stancion and backhead. Theres a couple of lubricators that aren't in the photos, but cab interior is done. All the backhead stuff is from Laurie Griffin.


    [​IMG]


    [​IMG]


    [​IMG]


    More water tank action next........
     
  9. Nick Dunhill

    Nick Dunhill Western Thunderer

    ....the plan is to glue strips of lead sheet inside the tanks and then close them up. I thought it prudent to build splashers inside the tanks first.


    [​IMG]


    [​IMG]


    [​IMG]


    [​IMG]


    I thought it'd be a good idea to build up the loco as built so far to check all fits, and it does!


    [​IMG]


    [​IMG]


    [​IMG]


    It is such a little simple loco in comparison with the brutish W class in my other build! If you are going to Reading on saturday come and have a look at it. Just the boiler to go!......
     
  10. P A D

    P A D Western Thunderer

    Hi Nick,
    So you've put the paste board away for this build. :))
    Cheer,
    Peter
     
  11. Nick Dunhill

    Nick Dunhill Western Thunderer

    ....boilers! The etchings Mick D did for me already had some of the boiler/firebox/smokebox formers included, but I needed extra ones and cut them from 0.4 mm nickel silver.


    [​IMG]


    Firstly I made the smokeboxes. The etches did have parts for the wrappers too, so this job was pretty easy. Form the wrappers into shape round suitably sized bar/drill shanks and solder up. The main curve I did by hand using a 20mm bar. Then I introduced a former and marked the positions of the reverse curves. The reverse curves were (slightly over-) done with a 7 mm drill shank. The wrapper was centred over the formers, and the formers brought to the front edges of the wrapper using a steel rule layed across the edges, you'll need to use your 3rd and 4th hands! Tack the main curve of the wrapper to the formers and then carefully unfold the return curves to match the lower parts of the formers.


    [​IMG]


    [​IMG]


    The boilers are a lot easier. A rectangle of 0.3 mm nickel silver was cut. {lenght required x [(diameter of former-thickess of material) x pi]}. This was shaped on my slip rollers. Put the ends of the sheet backwards through the rollers first to form the required curve. This prevents the rollers producing a flat end section to your tube. See here:




    [​IMG]


    The boiler bands were added from 0.2 mm strip (I know, I just like adding boiler bands) and cast tightening cleats soldered on. The boiler furnature castings were (extensively!) fettled and test fitted. (Do we all know the trick of laying abrasive paper round the boiler and 'lapping-in' the curved fixing flange of a chimney or dome?)


    Note to pattern makers and casters, please please please stop making chimneys that are solid down the middle. It takes ages to bore them out, it has to be done by hand because you can't hold them in anything. Brass cast ones are just impossible to bore out and I just weigh them in.


    [​IMG]


    As a finishing touch I scored the boiler clothing plate join along the top of the assembly and added some fake set screws.


    Next I finish the build with the last boiler details and some tablet catchers.......
     
    Rob Pulham, Deano747, JimG and 7 others like this.
  12. Nick Dunhill

    Nick Dunhill Western Thunderer

    Oh, the holes in the footplate ahead of the tanks are for some home made oil pots.


    [​IMG]


    [​IMG]
     
  13. mickoo

    mickoo Western Thunderer

    The roller trick only works with certain rollers, those where the top and bottom are directly above each other. The GW models has rollers in an inverted V so this trick will not work.

    Time for a new set of rollers me thinks !
     
    Len Cattley, BR Tony and Dan Randall like this.
  14. Nick Dunhill

    Nick Dunhill Western Thunderer

    Yep. Mine are the ex Metalsmiths, now Midland Railway Centre ones, and are pinch rollers, with the adjustable formimg roller in front, as the video. I was lucky and got them 2nd hand off eBay for a very good price.
     
  15. mickoo

    mickoo Western Thunderer

    You still run the risk of a flat at the start but it is greatly reduced with that design of roller.

    The only effective way with the inverted V style is to make the wrapper over long, there is a formula depending on roller dia/spacing and final sheet dia to calculate the amount of extra you need to clear the flat.

    Once rolled just trim back to the section where the smooth bend starts.
     
    Len Cattley and P A D like this.
  16. mickoo

    mickoo Western Thunderer

    Wooden clothes pegs, you may have to whittle the hole out a little but they'll hold a chimney in a vice to allow drilling. Take it easy with lots of lubricant and work up through the bit sizes.

    Failing that, ive drilled out softwood before to roughly the right diameter, then split down the grain with an axe to make a wooden clamp, soft wood tends to deform and match the outer profile better.
     
    Rob Pulham, Len Cattley, AJC and 3 others like this.
  17. Peter Cross

    Peter Cross Western Thunderer

    I have the GW rollers. I use a carrier for rolling cylinders. Normally a thickish piece of card longer than the cylinder it then Carries the first and last bit at the right curve.
     
    Rob Pulham likes this.
  18. Ian@StEnochs

    Ian@StEnochs Western Thunderer


    My rollers are home made Vee type. To get the ends of the sheet curved I just gently swage the end over the top roll with a hide mallet, both ends and then roll the remainder. Works for me.

    Ian.
     
    Nick Dunhill likes this.
  19. mickoo

    mickoo Western Thunderer

    It does, but you still get a bit of a flat, even with a corresponding sheet of similar metal you still get a partial flat.

    Normally it's fine and barely visible, bit for some of the work I do it simply isn't acceptable, especially when the final product carries a high gloss finish, then any slight crease or dents and dings show up like a sore thumb.
     
  20. mickoo

    mickoo Western Thunderer

    That requires a certain amount of skill and dexterity to give a smooth finish, sadly my career has kind of knocked those skills out of me.

    Image1.jpg

    One of my more 'frequent' uses of a 'ammer......recover the panzer belt and knock the trough back into shape.............. slightly more robust than sheet metal in 7 mm ;)

    For the record, 27 m high but anything more than 5 or 6 is academic in reality.
     
    Len Cattley, Rob R and Peter Cross like this.