Dean 044 Tank Loco No 34/35

[bertiedog]

After tracing drawings for the loco, a 7mm version of the Dean 044 Helston and St Ives tank engine is under way.

 

http://www.rmweb.co.uk/community/index.php?/topic/133203-urgent-appeal-for-details-and-drawing-of-gwr-no-3435-dean-044/&do=findComment&comment=3127168

 

Trying for a faster project, all brass body and fittings, cast iron wheels and custom bogie, Pittman motor and worm drive and a semi compensated unsprung chassis to get proper weight distribution.

 

Ex MRN drawing partly redrawn, under fair modelling use.

 

No pickups on wheels, power from drivers returned to bogie wheels, no drag or friction.

 

Ball raced main axles, and micro races in the bogie for the axles.

 

There is a sub chassis within the frames than pivots with the drive gear to maintain full contact with the track for adhesion.

 

 Pack of flat brass sheet off cuts bought from Ebay, mainly .7mm flat, a bit thick, but makes construction so much easier, adding heft and weight. There is not much plate work on the body anyway, and it has a nice open cab, a type I love to build. Edges can be thinned where needed for appearance sake.

 

The motion between the frames will be rigid, and for appearance only. Brass tube boiler, with wrapper rolled for firebox and smokebox, all lead filled except for motor space, which is entirely hidden in the firebox.

 

The pivoted wheelbase gives super smooth running and max traction for an 044 loco.

 

Wheels on order from Walsall's in cast iron, to be machined in the workshop to fine scale 7mm standards compatible with Peco points and track.

 

The bogie wheels will be stainless steel on stainless axles with ball races in the axleboxes. milled from brass on new CNC mill..

 

 

Dome and safety valve cover in brass bar turned on lathe, and the same for chimney.

 

Have to source Victorian driver and firemen, perhaps topper and bowler hat.

 

For once I have built these locos before, in 4mm and P4, so no problems or surprises to come in a seven millimetre scale.version.

 

Photos will be posted with new Olympus camera, when it arrives, not smart phone shot's,

Stephen

 

[bertiedog]

Apart from AC Stadden figures who list 7mm driver figures for a Dean Single, are there any other metal cast figures available for the late Victorian and early Edwardian period?

 

 

Not much else has come up on net searches so far,

 

Stephen.

 

[Simond]

Stephen,

 

I’ll be watching your progress with great interest. I like the “American bogie” approach, and as you say, no pickups to adjust, but I’d caution you against using ball bearings to carry an electric current, it will ruin them. Chances are, in an application with a half-amp motor, it might take a while, but I would suggest you avoid the risk by fitting a wiper to contact the axles - this will be easy to fit, and add negligible friction.

 

Google “electric damage to ball bearing” for more info.

 

Best

Simon

[bertiedog]

Stephen,

 

I’ll be watching your progress with great interest. I like the “American bogie” approach, and as you say, no pickups to adjust, but I’d caution you against using ball bearings to carry an electric current, it will ruin them. Chances are, in an application with a half-amp motor, it might take a while, but I would suggest you avoid the risk by fitting a wiper to contact the axles - this will be easy to fit, and add negligible friction.

 

Google “electric damage to ball bearing” for more info.

 

Best

Simon

Never had damage to any races when lubricated with correct grease, I use Labelle with PTFE, and the current and voltage would be low with most speeds and loads. I worked in scientific instrument making where bearings did pass current, but it took a lot to break down the surfaces.

 

Very high currents will actually cause rotation of a ball races, a crude  non magnet motor..

 

I think in models the lack of friction, and noise, from rubbing pickups outweighs the wear issue. If the axle is making contact it would in theory be getting only half the current if the coupling rod is dividing the contact between the wheels.

 

The best alternative would be a slip ring over the axle, made in leaded bronze, running on the polished stainless steel, with a spot of electrolube on it.

 

What i don't want is plunger sprung pickups on both sides. these really add drag.

 

The cast iron wheels will have centre insulation on one side, made from glass filled hard nylon.

 

Stephen.

[bertiedog]

 Most of the materials are too hand in the workshop, but trying to get 1mm seamless brass tube for the boiler to save rolling and soldering into a tube. it should be 28mm,, but the nearest is 30mm , an acceptable error. The firebox and smokebox will be wrappers over the tube, rolled to fit. Boiler bands in etched nickel silver strips.

 

The frames will be 1.2mm brass plate the same for the inner frame structure with the wheel bearings mounted in cups soldered to the subframe that pivots. Any frame spacers will be square brass bar, ends tapped for 6ba countersunk screws hidden by wheels of soldered over and sanded flush.

 

The frame ends are filled with plate brass to which the buffer beams are screwed from inside.

 

As it is 7mm scale most rivets fitted will be drilled holes filled with wire, or brass dress makers pins with head machined down a bit for larger sizes. If you buy these, then take a magnet to check they are brass, not plated steel.

 

Most tapping and screwing will be 6 ba, 8 ba and 10 ba.

 

Each part above the footplate will be a sub assembly and screwed in to place, the plate parts having angle section or solid brass square section soldered in place and drilled to take screws to secure each assembly. Most platework will be .7mm brass for weight and strength.

 

Brass screws on bodywork and steel screws and bolts on the chassis.

 

The brass fittings will all be turned from bar or plate, like the front brass cover on the firebox, safety valve covers and dome, and chimney, same with whistle and backhead details..

 

The various boxes and lubricator and sand boxes will be solid, drilled and tapped and screwed into place.

 

The buffers will be turned from stainless steel bar. Brake gear in steel and brass and heat treated to darken the steel down, and then blackened with gun black. or copper carbonate on brass parts.

 

The motor and gearbox are fitted for 4mm axles to fit the ballraces on, and there is a complete 30:1 worm gear drive already fitted in an enclosed gearbox. that should fit the space.

 

Stephen.

[bertiedog]

Decided the thick plate was too thick for the main footplate at 1.2 mm and found some ,5mm brass instead. which is flat plate as well, and can take a strip of the .5 mm in a groove along each edge cut on the milling machine, This acts as the side strip valence, complete with the profile at the front, but the steps at back will be soldered on.as a solid piece with steps would be wasteful of material.

 

The ends have 5x5 angle brass soldered on to take the buffer beam bolted on, This is confined to within the frames width so that frames use the angle strip as location.

 

Both the sides and the buffer beam have been drilled for rivets using brass pins. The head is reduced with a fine needle file, fixed to a jig so that the pin rests on the wood as it is rotated by a Dremel type drill The wood rest guide forces the same diameter on each one, then the head is rounded with finr emery paper glued on to a board.

 

On soldering the side valence on, the pins are fitted with solder paste and heated in one go to secure them, same for the buffer beam. Cupalloys do proper solder paste. All Soldering is done with Bakers fluid flux, with pure tin solder and 60/40 lead solder plus lower melt solder for details

 

Once solid with the valence and buffer beams the space over the frames under the boiler can be cut out by fretsaw or more likely on the milling machine.

 

The opening is just narrower than the frame inside back to back, but goes full width at the firebox end, and stops at the backhead position. This gives clearance for the cladded firebox. but leaves an over hanging edge around the motion area.

 

No cut out is used under the smoke box, which has a brass plate bottom, drilled and tapped to be screwed down to the footplate.

 

Next is the front plate of the cab, again fitted with brass angle on each side to bolt down.

The centre line of the boiler is determined by the back of the smokebox and checking on the drawing, and then the front cab plate can be marked and a disk fitting the tube bolted on.

 

The boiler can be adjusted level at this stage, and the disk soldered up solid.

 

The area of the tube in the firebox can be half cut away. to get motor space.. An end plate is added.to the boiler with tapped holes to assemble it into place.

 

The front just rests on the smokebox ring disk, no need to secure really, although a bolt into the smokebox back could be used, accessed via the smokebox door.

 

By now the main structure is complete and the sides of the cab. with soldered on front and top can be added. and a box made in brass for the coal area, again bolted into place on the footplate.

 

The backhead can be cut out to shape and bolted to the cab front plate. The roof can be attached with an angle iron strip to locate it and be bolted on with screws from inside, filed flush outside later in finishing.

 

By now the body is approaching completion. and the work moves back to the chassis.

 

The profile is cut out and frame spacers marked in and axle positions drilled, using the frames as jigs to mark out the rough connecting rods..

 

In this case the inner frames are drilled with the other parts. but then the outer frame holes are re-drilled 2mm larger to allow the inner chassis to pivot. Once the inner chassis is on its frame spacers and checked true, it is attached to the outer frames with clamps, and held in line by dummy axles, the pivot points is drilled each side, tapped in the outer frames, the inner opened up to take a shouldered screw.

 

The inner chassis is removed and fitted with bearings, and then assembled ready to have the wheelsets added, in this case pushed on.

 

Once quartered the rough rods can be added and running checked for binds.

 

One of the frame spacers on the main chassis should align with the bogie pivot and allow a post to be fitted to take the bogie bolster. The bolster hole in the bogie should be a slot to allow a bit of side movement, with a phosphor bronze spring to centre it on straight track. The whole frame spacer should be made from Tufnol to insulate the bogie from the chassis and body. washers cab be used to level up the chassis, fitted on the post. A nut and light coil spring retains the whole bogie. allowing a little rocking play under pressure.

 

Next is adding the motor on a frame attached to the inner frame, and connecting to the gears.

 

At this point the body and chassis should run, and then it is taken apart to add all the detailing.

 

An important point is the inner chassis must clear the mainframes by about .25mm to allow painting. on assembly, with washers being added which prevent the paint rubbing.

 

All the rest is a lot of detailing all round from boxes to hand rails, coal rails, whistle and backhead detail, plus any edging and polished brass parts like dome and safety valves

 

The brake gear should be attached to the sub chassis and move with the wheels as it pivots.

 

Buffers will be sprung, made in stainless steel.The bogie will be all brass and nickel, with milled axleboxes, and turned leaf springs made in a ring and sawn up. Stainless steel disc wheels will be fitted on 3mm axles with outer 2mm stubs to fit the ballraces on. Insulation by tufnol centres on one side.

 

Plain DC 12 volt operation, no chips or complex DCC here.

 

About a months work, but health problems might slow it down a bit. At least underway, with wheels to be ordered on Monday.

 

Posting as work proceeds with photos.

 

Stephen.

 

 

[bertiedog]

​One very important thought is the buffers will have to be mounted in tufnol to insulate from the loco along with the sprung couplings as there could be a return path to opposite polarity via stock that is only one side insulated.

 

The thick beam can have large holes drilled for each item and plugged with tufnol fitted in a press with loctite. The whole beam can be sanded down on the linisher belt sander and after painting should be invisible insulation.

 

Stephen.

[bertiedog]

Has nobody any thoughts on period figures apart from AC Stadden? I did look at Aiden Cambell, but the figures are too modern or frankly some out of proportion if standing. His crouching or action figures are excellent.

Are there any other overlooked quality makers in metal.

Stephen.

[Poggy1165]

You could try "Heroes of the Footplate". Though I'm not sure who has them now, as the originator no longer retails.

 

(EDIT) Found them - they are with Invertrain.

 

Great to see someone attempting a really interesting loco like this!

Edited April 14, 2018 by Poggy1165

[bertiedog]

You could try "Heroes of the Footplate". Though I'm not sure who has them now, as the originator no longer retails.

 

(EDIT) Found them - they are with Invertrain.

 

Great to see someone attempting a really interesting loco like this!

http://www.invertrain.com/maker.php?maker=Heroes+of+the+Footplate

 

Iinvertrain do the range and more comprehensive than others, look well proportioned and no gorilla arms or midget proportions as in some 4mm figures. They do 1900 period, but hats can be altered a bit as well.

Thanks for the reference to the range.

With the open cab they have got to look good.

 

Stephen

[bertiedog]

I think the figures to get are the Ivertrains ones..

 

 

 

Fully standing figures, as the cab area is not that big, and the details on the figures can be customised easily in 7mm scale, beards, and a bowler hat for the driver figure.

 

Stephen

[bertiedog]

Does any body have a drawing they could scan or photograph of a Dean round top boiler back head for No 34, or any similar Dean type. My drawings cover Belpaire variants only.

Thanks

Stephen.

[bertiedog]

Would the Dean Goods round top backhead arrangements do after removing the spring tops.

 

 

The shot appears to come from RM web in 2013, pnly using as cropped reference

Edited April 14, 2018 by bertiedog

[bgman]

Does any body have a drawing they could scan or photograph of a Dean round top boiler back head for No 34, or any similar Dean type. My drawings cover Belpaire variants only.

Thanks

Stephen.

Hi Stephen,

 

I've had a very quick scan through my Pictorial Record of Great Western Engines Vol.1 by Jim Russell and on page 151 I found this photograph albeit another oddity ( which I really like ) showing the cab of No.36 which had a similar shaped firebox

 

 

Don't know if it helps ?

 

I will follow you build with great interest.

 

Grahame

[bertiedog]

 

Yes pretty much a standard layout, needs to look neat rather than detailed, it can be built off the loco and simply bolted into place on the cab front.

Stephen

[bertiedog]

Upon reflection, the axle size for the gears I have is 3/16th imperial, so rather than sleeve a metric ballrace or find 3/16th races sufficiently small, I will fit bronze bearings bored to 3/16th.

The bearings can be smaller and will solder into the sub frame using dummy 3/16th axles to align them.

Stephen

[bertiedog]

Start made on the bandsaw to cut out plate work, but no assembly till all the parts are done to size to check the practical fit of the whole thing including the boiler.

Pairs are marked out on one, and superglued to the un-marked side, Each edge is cut with a clearance to the marked line, and then the pair are sanded on a bench sander to exactly the marked line.

The roof is easy, but has to be curved, so brass heated to near red  before bending.

The same is needed for the firebox and smokebox.

Also started the dome and fittings from brass bar scraps

Stephen

Edited April 16, 2018 by bertiedog

[Michael Edge]

 

BACKHEAD 36.jpg

 

Yes pretty much a standard layout, needs to look neat rather than detailed, it can be built off the loco and simply bolted into place on the cab front.

Stephen

 

 

Don't forget No.36 had a much bigger firebox than 34.

[bertiedog]

As long as nobody has a reference to No34's backhead as a photo or drawing, from Russel etc., then I will scale the layout from the bigger boiler.

 

The front plate of the coal space is another area without details, a shelf and coal chute should suffice, the figures partially cover seeing all  the detailing anyway.

 

The cab edging around the curved cut away section will need a nickel silver strip added as a strip soldered on over size, and filed down to size using a file and a plate of the thickness required. Usually flush on the inner surface.

 

The windows can have small brass turnings added as frames, with plastic as glazing. The backhead fittings can be brass and copper wire, all polished over a black finish, with the interior of the cab in cream colour..

 

On crew clothes of the period I assume grey jackets and blue trousers, or does anybody know the GWR  colours most used about 1900.

 

Today's main ob is the footplate and buffer beams, and marking locations for screws to attach the smoke box, cab front plate and the coal bunker. The bases can be superglued on to mark through the holes to allow drilling and tapping the parts, 6ba or 8ba as needed. The glue can be broken afterwards and cleaned away with heat and solvent.

[Signalman Rich]

Hello Bertiedog.

Thanks for posting progress on your build. I look forward to seeing photos in due course. You are probably well past the boiler manufacture so you may not need to have the information - copper heating pipe as used  in central heating is available in 28mm diameter. Your neighbourhood plumber probably has some offcuts.  On uniforms :  my first edition of Great western Way by Jack Slinn suggests that station staff were in "blue serge jackets and trousers by 1902."  Prior to that, from my observation, it was not unusual to see the older drivers still wearing white fustian jackets. I model Broad Gauge pre 1892 so am more familiar with earlier uniforms, but there always did seem to be considerable variety in the uniforms of footplate staff, some of the early ones wearing fustian jackets and trousers, or even green corduroy like the porters, not to mention a variety of headgear, partly following the civilian fashions of the time.  Modelu produce some very fine figures of footplate staff which can be modified to an earlier appearance without too much trouble.

 

Hoping the above may be of some help. 

Best wishes

Rich

[bertiedog]

 Major change to the specification, to suit my friends 0 gauge taste, is it is to be three rail pickup, which means no insulated buffers or couplings and totally accurate wheels on solid axles, no plastic bushes required anywhere, and no problems around the rear bogie with shorts. 

 

A skate pickup plate or nickel silver "spoons" on phosphor bronze springs will be added on a bottom cover plate made in glass fibre circuit board. The should be enouth clearances for the spoons or plate with a bit to spare for up and down movement. The spoons would be set about 4 inches apart to allow operation over points gap. Obviously still not suited to tight O gauge curved set track like Lionel.

 

A four inch skate would also fit, with slightly up curved ends.

 

I had thought of the copper pipe, but may roll a thinner brass one as it is easier to solder on to, the thick copper soaks up the heat a bit too much. 

 

The copper pipe does allow grooves to be cut in it for boiler bands to be set in, and have better joints made with rebated ends

 

But in this case the ends are disks inside each end, with few if any clearance problems. The disks will have tapped holes to secure to the smokebox, and cab plates, with 6ba screws as they are hidden away from view. The dome and safety valve cover will be bolted on as well with 6ba screws, not soldered on. It allows for more adjustment.

 

Wheels ordered and should be here soon.

[bertiedog]

A slight spanner in the works is the tightest three rail curves from MTH in the States would be impossible for this loco despite the relatively short wheel base and bogie.

 

But with slightly narrower frames than GOG standards would accept, and allowing side play on the front and driven axle, plus as much side movement that the bogie can take, it should go around a 3 to 4 ft radius with ease.

 

It makes the sub frame a bit narrower, but that does not matter. The wheel profile will need a bit of altering to give a Back to Back to go through the MTH points.(and only the bigger radius ones).

 

I doubt that the loco will be run that much off a straight test track anyway, he collects rather than runs them.

 

0 Gauge standards are a bit of a nightmare once away from the GOG standard, and MTH/ Lionel adopt backwards comparability over scale far too often.

[bertiedog]

Checked on the drawing board and computer, it shows that about 1.5mm extra play each side on the front axle and driven axle, plus a swinging rear bogie should go through just under 3 foot radius. The problem at the rear is the cab steps over the bogie.

 

It might need a centering spring on the lead driven axle to keep it dead straight on straight track. But usually the pull via the coupling will keep it straight, and really the play is minimal compared toy train standards. The bogie was going to have light centering springs anyway.

 

The wheel profile will be fine scale flange height, with a courser root curve to help running through the points, and current MTH back to back will have to be used.

 

All in all a curates egg of mixing compatibility with old US standards and three rail.

 

Stephen

.

[bertiedog]

The use of older three rail standards for the running gear has some benefits in the lack of need for any insulation on the wheels and ease of running.

 

It will need sub scale width frames, which will barely show but eases the fitting of brake shoes and side rods which cannot short out against the wheels tyres. The narrowed frames are to allow side play for MTH curves, except for O 31 type, too extreme! It should deal with 4 foot radius with ease, maybe a bit tighter due to short wheel base and bogie.

 

The downside is the centre pickup which will be a two spoon design, on flat phosphor bronze strip , bolted dry onto a  printed circuit board bass,left with a pattern to provide connection to the motor via a wire and suppressor circuit on the top of the PC board Power can also be sent to a firebox glow flicker LED light as requested by my friend.

 

 

Outline of  pickup, not to exact scale, which allows for a raised 2mm centre rail for the spoon ends to run on. The springs are tensioned to run on the rail top, but not to drop too far over the point gaps.

 

It may need a small restraint wire loop over each spring to stop the vertical movement going down too far., Up movement does not matter,

The spoons are nickel silver with smooth curved bottoms with a bevelled edge to front and back on each to ensure smooth running over points.

 

I have some old Bassett Lowke 3 rail O gauge track which is the same over all dimensions as MTH to test the loco on.

 

Stephen

[bertiedog]

More scale drawing of the pickups under the loco chassis. I think the proportions will work well with out any extra pickup under the bogie.

Feels like a real vintage loco all round with 3 rail operation.

 

 

I think a restraint wire will be needed or a screw through the spring to set the lowest position more reliable.

 

Any comments from experienced three rail users appreciated;

 

Stephen.