Judith Edge kits

[Michael Edge]

LMS No3 under construction in 7mm scale.

The etch is a straightforward enlargement of the 4mm one, although not the final production alterations, etched in .022" n/s. Construction is much he same, spacers and compensating beams added. The straps holding the beams against the frames are bent up from bits of scrap, I find this the easiest way to keep them in place. Axle bushes added to the inside faces of the beams, the centre ones sawn away somewhat to allow for the gearbox. Cylinder ends temporarily slotted in here, also Slater's wheels fitted to check frame alignment is square.

At the other end the trailing axle is in swinging arms, rocking under a knife edge. Ashpan sides added, a narrower spacer fits in here, holes shown for pony truck pivots and two 8BA fixing screws.

Some parts prepared now, slidebars are laminated from three layers, also rear cylinder covers - I find etched slidebars much quicker to fit than any other alternative, cast ones take too much fettling and rectangular or square section is rarely available in the right size. The other item is the slidebar bracket, laminated from two layers.

 

Fitting the cylinder ends and motion bracket is easier if the slidebars are ready to check in place, they peg right through the cylinders but are not soldered in place yet.

With the cylinder ends soldered in place a length of tube is fitted to carry the piston rod, final alignment check now with 2mm rod threaded through, should align with the axle centre in mid position - which it does. I'll leave the frames now until most of the body is built.

[JeffP]

I like to see the piston rod supported like that along it's length. I used to do the same in 4mm.

[Downendian]

Just a quick note to thank Michael for excellent service. He noticed my post on another thread regarding sourcing Ruston & Hornsby logos for my Judith Edge PWM650, as they weren't in my old kit. An etch provided now in the kit was sent to me after a PM exchange, and arrived last week.

Many thanks Michael.

Neil

[Daddyman]

The straps holding the beams against the frames are bent up from bits of scrap, I find this the easiest way to keep them in place. 

Interesting. Do you use this method in 4mm too? I found the beams on the Kitson just waggled around so much, getting bent all the time during construction, that I had to abandon them and build it rigid. 

[Michael Edge]

Yes, quite often but I've built plenty of locos without anything restraining the arms.

[Michael Edge]

Back to the 7mm Fowler 3P now. Most of these illustrations are equally applicable to the 4mm version now on sale.

With the footplate more or less complete I start with the cab front. This locates on the footplate with two tabs, front window frames added in the flat first.

One side tacked on, in just a few places to check it's the same distance from the edge all along. I'm glad I don't have to punch out all those rivets for this one! The cab sides curve over into the roof, stopping at the rainstrip, this shape needs to be checked against the ends before fitting. Half etched lines put the curve in the right place without too much effort.

Flux (phosphoric acid) on both sides of the joint, heat and solder from the inside until a bright line of solder appears on the outside - just about visible in this photo.

I've recently changed to using a solder with 2% silver (62/s available from Hobby Holidays) from my usual 60/40. It has a slightly lower melting point but flows much better and I think has more mechanical strength as well.

Both sides on and checked for square across the fronts, the tank front folds in. This is a bit of a compromise, the fold is slightly rounded but produces a an accurate shape here.

Cab back next but this needs the window bars adding first, easy enough once you have all the holes in the right places. Etching is much easier than marking and hand drilling for this. Wires bent to a U shape, a scrap of etch to space them off and solder from the inside.

This is how to hold them, fingers work better than any clamp here, the iron doesn't need to be on the joint for long enough to burn them.

When they are all on it looks like this but all gets filed/sanded flat before assembly, important otherwise it's very difficult to fit glazing later.

The cab back locates in the same way as the front, bunker sides soldered in place now. All this is being done with the frames bolted in to keep the footplate straight and flat - this is one of the reasons why no more work was done on the frames before completing the rest, otherwise I would just be knocking bits off all the time I was working. Bunker back fitted next.

The bunker front folded and fitted (I should have fitted the coal door first but forgot), the inner cab floor is soldered to the frames.

The cab doors and recesses next, these fold up but it's important to fit at least the two rear handrails first, otherwise you can't get the soldering iron at the back.

Progress so far, next some essential detail on the bunker back before I put the floor in, then either complete the inside of the cab or start on the boiler. This photo shows why I leave steps off until the boiler is on - I need the lower edges of the buffer beams to check that the loco is still square and not twisted. Once the boiler is on it won't twist, most of a loco's torsional stiffness is in the boiler. The tank tops are in one piece, the cross bars will be removed later.

 

 

 

[Horsetan]

^^

That's a weird set of holes in the cab front. Almost Emmenthal in etched nickel silver.

[Michael Edge]

Space was getting tight on this etch! I only had one 18"x12" sheet, I had to put frame spacers and balance weights on another test etch.

[PenrithBeacon]

Nice tutorial, thank you

[Michael Edge]

Next job is all the beading on tanks, bunker and cab opening. Most etched kits have this as part of the etching but there are a couple of big disadvantages to this so generally I don't do it. Etched beading usually looks a bit flat and square rather than the half round appearance it should have, more importantly etching away half the thickness leaves very flimsy tanks and bunker. I go back to older scratchbuilding techniques for this and use wire along the top edge, a half etched ledge helps to fit it here but it isn't really necessary. I am aware that a lot (but not all) of this beading is a strip along the top edge which overhangs both sides and some kit designers provide a strip with an etched groove to reproduce this but I'm not sure it's worth the effort in most cases. The wire method can be applied both sides if you really want this.

 

 

Start with a length of soft brass wire, I used to use tinned copper fuse wire for this job before coils of soft brass were readily available - now fuse wire has all but disappeared. Put one end in the vice and grip the other with pliers, gently pull it straight, it will stretch a bit but don't let it snap. You now have a length of straight softish (it will have hardened a bit when stretched) wire.

 

 

 

Starting at one end solder the wire in the half etch. I usually go this way round because I'm right handed, left handers may prefer to go in the other direction.

 

 

The soldering iron is only applied to the top edge (flux all over though), capillary action will take the solder under the wire.

 

 

A suitable size rod or drill is useful to get an even curve round the corners.

 

 

When it's all on smoothe the top surface and gently scrape the join under the beading against the bunker side to clean out any excess solder. 

 

Next job will be the inside of the cab, there's a fair amount of guesswork here, I've never found a good photo of the inside of the cab and as far as I know no drawings have survived. The riveting pattern on the later locos show where the tank goes inside the cab and there must be some sort of splasher since the wheels come above the floor. Details of the coal door are equally shadowy but a rivet pattern on the back gives something away, the handbrake position is constrained by being inside the frames and it's definitely on the RH side.

 

 

No etched parts for this so it's back to cutting sheet metal, .010" n/s in this case. On the left is the start of one tank/splasher cut out with a piercing saw and the instrument seen above it. This is a "skrawker" ground from a No11 scalpel blade, drawn a few times along a line to be cut or folded - for cutting flex the metal gently back and forwards until it cracks, most metal can be cut this way unless it's very soft. Note that most sheet material is cut from rolled coils and has definite tendency to crack more easily in one direction (along the roll) than the other, a bit like going with the grain in wood. On the right is the folded shape, if the outside appearance isn't critical as in this case, the metal folds much more easily and cleanly with the scored line on the outside.

 

 

Tops soldered on and one box assembled in the cab. This is done with the floor in place, the boxes are soldered to the cab, a couple of tack joints at first, then take the frames out and complete them all from underneath/inside. The reverser will fit on top of the LH tank.

 

 

 

 

 

 

 

[Michael Edge]

Little and Large this morning.

 

 

I took some time out to fit the valve gear on the 4mm 3P, it's spindly and a bit fiddly but works well. The return crank is one layer with a tiny washer to fit on the small end, rather than my usual two part lamination. The expansion link is assembled from three pieces with the radius rod between two of them. The valve spindle guide is laminated from two layers and soldered to the inside of the footplate angle, as usual the model is assembled in mid gear, the link could be made to work in forward or back gear but a working valve spindle crosshead and guide would be needed.

[Horsetan]

.....the link could be made to work in forward or back gear but a working valve spindle crosshead and guide would be needed.

 

Is that do-able in the space available?

[Blandford1969]

I'm sure somewhere I have got a drawing showing the elevation of the cab front showing the backhead and rear showing the shovel plate, etc. I will have a look at home and let you know.

[Michael Edge]

Is that do-able in the space available?

 

Maybe, maybe not, I don't really think it's worth the bother. I'm quite happy with locos in mid gear, that's what they usually are when they are stood still which is when you usually examine them closely. Same reason why none of my locos have a crew, looks really silly when they are all lined up on shed - as mine frequently are.

[Blandford1969]

PM sent with a drawing.

[Michael Edge]

We will be doing the usual kit building/design demo at York over Easter, different place again this year, we are stand 41 on the ground floor near Squires. With the objective of encouraging modellers to actually build something, bring along anything built or part built (doesn't have to be from our kits) that you are either proud of or having difficulty with and I'll congratulate or help as appropriate. We usually spend quite a lot of time explaining how soldering is actually quite easy and not a difficult black art so look for encouragement if you haven't tried it yet.

Michael and Judith Edge

[delticfan]

A bit off topic but I remember some CAD type drawings of the Woodhead EM1 in 7mm that were on here some time ago, do you have the link to them if still exist. Looking to do some scratch build effort.

[Michael Edge]

It should still be there but I've no idea how to find it.

[delticfan]

It should still be there but I've no idea how to find it.

Thanks, I have stumbled across it once but can’t find it, will keep looking I’m sure I will find it.

[5050]

We will be doing the usual kit building/design demo at York over Easter, different place

Not in a draught then?

[Michael Edge]

It was more like a wind tunnel than a draught!

[St Enodoc]

It was more like a wind tunnel than a draught!

Like sitting in the pay box at the Corn Exchange?

[Michael Edge]

Back to the 7mm 3P today, boiler next.

 

 

Starting with the firebox, this is the paper pattern stuck on to .010" n/s with double sided tape. First line to cut it off made with the skrawker shown earlier, you can see the curls of metal this produces.

 

 

Held in the vice and gently waggled to break it along the line, taking care not to bend the metal anywhere but along the line. This vice has extended jaws for this purpose.

 

 

This is what it looks like as it finally breaks off.

 

 

For a plain rectangle such as this the same technique is used for all four sides, no sawing needed.

 

 

 

While it is flat, holes for the washout plugs, whistle and safety valve base are centre punched. When using a paper pattern like this don't mark hole positions with a cross, use a small circle, you can't feel a cross on paper but you can see the centre punch in the middle of a circle. The lines across are cut and scribed to show the position of the cleading band.

 

 

Next the corners are bent around a 1/4" rod, the lines on the paper show where this should be.

 

 

Lead sheet on the inside of the firebox to fit the washout plugs (1mm square brass) in, the completed firebox wrapper locates in a groove on the cab front.

 

 

The boiler is made in the same way from .010" brass, no need to cover all the brass with tape, a strio  at each end is sufficient. Cleading bands marked and the position of the dome.

 

 

Boiler rolled, tacked along the bottom and checked against the drawing.

 

 

The top rear needs a small notch to allow the boiler to fit under the firebox wrapper, if the wasn't a tank loco the same would be necessary at each side as well.

 

 

Smokebox front fitted (an etched groove would be useful here as well), the boiler built up at each end with a copper wire hoop. The smokebox of these locos was much bigger in diameter than the boiler. Etched wrapper in the background.

 

 

The frames will be bolted back in before fixing the boiler in place so this hole has to be cut for the frame fixing screw and nut to fit through.

 

 

Boiler tried in place, seems to fit quite well.

 

 

The wrapper is formed by hand, I don't use the rolling bars for this and no annealing is necessary for half etched n/s. I've cut "windows" out of the side where the handrail pillars will fit later.

 

 

Taking advantage of the lack of rivet detail on this early LMS example, the wrapper is quite roughly soldered on the end, excess solder can easily be sanded off.

 

 

Smokebox is tacked to the footplate at the end with a blob of solder.

 

 

Frames removed and footplate stood on a flat surface to attach the back of the boiler, squareness is vital here, this is why nothing below the bottom edges of the buffer beams has been attached yet, they are the reference surfaces until the boiler is fixed. Once the boiler is fixed nothing will twist the body, there's never any point in checking that frames are square, the boiler is most of the torsional stiffness and will pull it out easily.

 

 

The blobs of solder along the bottom edge of the smokebox/footplate join will be spread along by applying the iron underneath

 

 

Solder underneath shows where the iron was applied. Five hours work today and the most critical part of the job done - all downhill from here!

 

 

 

 

 

 

 

 

 

[Daddyman]

We will be doing the usual kit building/design demo at York over Easter, different place again this year, we are stand 41 on the ground floor near Squires. With the objective of encouraging modellers to actually build something, bring along anything built or part built (doesn't have to be from our kits) that you are either proud of or having difficulty with and I'll congratulate or help as appropriate. We usually spend quite a lot of time explaining how soldering is actually quite easy and not a difficult black art so look for encouragement if you haven't tried it yet.

Michael and Judith Edge

Will you be selling your normal range as well, Mike? 

[Michael Edge]

We'll have all the stock with us as usual.