NER EE-1

[cabbage]

I suppose I had better explain my obsession with this locomotive -but it began 42 years ago and has gone downhill since then... I think I am about 35% of the way through building it, and it is the third G3 model that I have built. When I first proposed building it friends told me, "You're mad!" this same viewpoint was echoed by one of the model engineering firms that I approached and I got thee polite -but very firm refusals. The problem with this loco are the six driving wheels. I have had to devise a method of making the wheels, allied to this I propose a track with, (for G3), very tight corners due to my location on top of a hill.

This is the infamous, "Snowflake Wheel", that defines the look of this locomotive.



The only bits turned on a lathe were the rim and the hub. The spokes are all hand sawn and silver soldered. Next Saturday is the Burton-upon-Trent Beer festival. The steel for the chassis has been: ordered, cut, and should be delivered on Friday. So, if we follow a similar patten the chassis plans, (plus beer mats for notes), will be discussed / worked on by a group of "madmen" during it!

regards

ralph

[MikeWilliams]

Rather you than me Ralph!

Can you explain the process please?  Turn the centre first - hold the tyre in a jig, solder in the spokes, then finish-turn the tyre?  I imagine all the bits are mild steel?

Mike

[John Candy]

Looks an interesting project and I look forward to seeing the completed loco.
Not quite clear which loco it is from the message heading.
Is it NER No.13, the massive 4-6-4 (2-CO-2) which never ran?
Will you be installing catenary ... that might well be a 'first' for G3?

John.

[cabbage]

I am first and foremost NOT an engineer!!! The tyre is first of all chain drilled on a mill and then most of the metal milled away to leave a square blank with a circular milled trough in it. The blank (a piece of 100mm sq BMS) is then clamped in a four jaw chuck and then attacked with a lathe tool to punch through. This leaves me with a round hole in square sheet, this is then turned out to 80mm dia. The spokes are made from tridents of 5mm sq steel.



Each one is then pinned with 3mm titanium threaded bar, (a piece of scrap from RR!), and then brazed to the 25mm dia hub -which was turned down at one end to 13mm dia. It is going to be a working Quill drive too...



The spoked hub is then fitted to the four jaw chuck and after some grunting the position of the cutting head is transfered to the spokes. They then have a dire attack of the angle grinder and bench grinder... The trimmed spoked hub is then CA'ed to the wheel rim and re-fitted back into the 4 jaw. Hammer taps precision align the tyre to the spokes(!) The CA is the "cured" with my wifes' hair drier. The cutter head is wound out to 96mm and I use it to score a mark. Then I attack it with the angle grinder, pretty it up on the bench grinder and then turn it to 96mm on the lathe. The CA joints hold the tyre to the spokes firmly enough for turning, (but then this particular adhesive SHOULD do!)

This is where I am at the moment.



I have decided to paint it NER Saxon Green -a colour it never wore...

And Yes, although it will run from batteries it will have functioning pantographs -as have all my G3 electric models. I use "Memory Wire" to raise and springs to lower them. I did "drop test" the design I used on my EF-1 and that has proved capable of taking 6 amperes each quite easily.

regards

ralph

[MikeWilliams]

Ralph,

I'm really impressed.  I did laugh however at your statement "I am first and foremost NOT an engineer" when you then go on to mention in passing such things as "metal milled away", "four jaw chuck", "titanium threaded bar", "brazed", "CA'ed" ...

Compared with most of us, I suspect you are more of an engineer than you realise.

I look forward to seeing the engine, and even more to seeing the quill drive in action!

Mike

[cabbage]

Well I suppose you had better see the rest of the plans for it too then...



Although I think the small preview JPEG is a little on the "squinty" size the
original is full (1:22.6 scale) size. This is as John has surmised the NER no.13
the 2-C0-2 electric locomotive originally designed for the Newcastle to York
electrification scheme. The envisaged design will have three 5 pole motors
each of 223g/m torque rating with a PWAM supply of 10 Amperes at 12 Volts.

As in the original, the leading and trailing bogies will lock , and unlock, when cornering.
The leading bogie was locked at high speed. (Above 50mph). The trailing bogie
was unlocked only when cornering... This of course all changed when the loco
"changed ends". This has required some inspired madness on my part, and the result
is based on 1920's style electromechanics rather than C21st PIC or Stamp systems,
although it was very close!!!

The batteries are located over each of the bogies with the "plates" towards the
centre of the loco to assist traction and C.of.G. I hope to get it completed by
the end of this year.

regards

ralph

[John Candy]

Ralph,
A most ambitious project!
I think the place for this is in the Members Only 'Scrapbook' section (where you can have a larger image)with an eventual article for the Newsletter.
One thing is certain (well almost...you cannot be certain of anything these days) and that is, it will share with the prototype, the distinction of being unique amongst G3 models.
There is (or was about 15 years ago) a large scale model on display in a cabinet at the NRM but I suspect that was G1.

John.

[cabbage]

Well the steel from "Rob" has arrived and as usual had to cleaned of all the "red chinese chicken dripping" that he insists on using for cutting oil. Much fun was had by father and son playing fit the piece to the plans...  I am going to have to change my type of "blue" that I use -normally I scribble over part of the metal with a marker pen and scratch. However this time the "blue" is rubbing off with handling.

Anyway this is what we have for one of the bogies:



I am half way through finishing the last of the 6 driving wheels and the next step will be to cut the 8 bogie wheels. And it the bogie wheels that I am stating to wonder about... In the classical manner they should have the axle fixed between them, however, what I am thinking of doing is fixing the axles and then mounting the wheels on double ball bearings. This "should" give the loco improved cornering ability. I do know that this was tried on the Midland and the NER itself tried something similar. The chief advantage of this is that the fixed axle can be thicker at the slide block in the horn guides and it will not be subject to rotational wear. The main minus point is increased wheel wobble as the bearings wear...

Time to dig out my slide rule and a large mug of tea(!)

regards

ralph

[cabbage]

To be honest neither the mug of tea or the slide rule were of any help... What was -was the crabby old english copper plate script of my late fathers notebooks. What I have decided to do, based on the observations and notes there -is to give my loco "Colonial" wheels i.e. no coning and axe edged flanges. They should be easier to machine and steer the loco through the curves, at the expense of "picking" at the frogs or the wing rails -due to the "fat" flange.

My father HATED "Colonial" wheels and Irish wheels and reserved their making for "Friday Afternoons", as it would take all morning to set the machines for the job -and then that left all weekend for the millwrights to get the machines back to "true" again...

My reasons for doing this are more practical then philosophical(!) Although there are several dealers for the "compound slide" that I would need to produce a UK wheel profile on my lathe -none of them will admit to having one in stock. If I don't like the way it corners I can always turn the wheels to the UK profile when I have found someone to sell me a "slide".

regards

ralph

[cabbage]

The small image shows the first of the eight bogie wheels about to be cut on my lathe. The 6cm sq 8mm thick "blank" has been drilled out to 8mm and the biggest nut and bolt I could find -"grunted" tight. At the moment I have two of them cut roughly to 5.8cm -the finish size is 5.5cm.

The results from "The Beer Festival Planning Session" are rather good -I am pleased to say, But I would be the first to admit that the constructional drawings now smell of: ale, cheese & onion crisps, and Chicken Tikka Madras... The design of "the spine" that carries the three Quill drives has met with "calculated"(!) approval -although there were some voiced thoughts on: "Perhaps it really should have more roller rather than ball races". The main problem I seem to be facing is getting my Snowflake wheels balanced -otherwise they will want to "hop" in their garland of drive springs and cause unwanted bashing of the tube axle holding the Bull gear!!!

The solution is; either to dynamically balance the Snowflake with drilling and inserting weights -OR (the method I favor) alter the tensions on the drive springs so the wheel doesn't want to move and is forced centrally. The first method requires putting the Snowflake wheel on an axle between two rulers and watching where it wants to "rest" (and then drill a bit of the heavy part of the tyre away). The second entails tightening/loosening parts of the spring compressor until the wheel "floats" centrally. The first method is probably the more correct -but with the second method (although more fiddly) means I can fine tune my Quill drive to the loco.

From the "design" point of view I am just using simple Hookes Law calculations to produce the spring specification that I require. Well in fact the spring rating is the average of the three positions that the spring will be in as it moves in relation to the Bull Gear and the Snowflake wheel i.e. static, driving, and braking.

All this has been made harder by the fact that my son has wiped all the pre-programmed equations from my hand calculator and I am having to do it via spreadsheet...

regards

ralph

[cabbage]

Well after a suitable pause due to "End of Year" and "other matters" -I am at last allowed to return to my loco... I have completed the turning of 5 of the 8 blanks required for the bogies, and all went well until the second "session" after last Sunday Lunch. The lathe decided to start up at full revs and refuse to obey the speed control. Then it simply stopped... I have unshipped the board and I am awaiting Chester Tools service dept to get it fixed!!!

During the wait I have been turning my attention to the lights and their connections. The strange red/white dual LEDs have arrived from Texas and I am chopping up lengths of "heat shrink" to make sealed connections with. Once threaded onto the wires they will be greeted by my teenage 25Watt Weller soldering iron -which despite its age is far better than the modern electronic Antex that seems to spend most of its time getting hot....

Tomorrow my friend from "The Welding Institute' is coming around to help me decide how best to begin assembly of my chassis parts. I know that my welding is anything but pretty -but it is strong and I am very good with an angle grinder(!) So, what is the next thing on my shopping list? The answer is the Bull Gears and the spring assemblies. I think that the best way to build the mounts for the Bull gears is to line up all the plates that will hold the Bearings for the Bull Gear and then to "bore out" with my boring bar to 32mm. I then plan to slice the bored plate in two and then weld a hinged clamp fitting to the two halves. This will clamp onto the outer surface of the ball race that supports the Bull Gear.

After some "inspired" madness I have finally decided on the structure of the Bull Gear... This will consist of two Main gears with four 3mm threaded holes through the boss of the gear. This will sit inside a length of 22mm copper heating pipe and then this sits inside a length of 22mm pipe joiner. This gives me an external diameter of 25mm(!) The ball races are then fitted and the other Main Gear fitted and then bolted up tight with 3mm bolts.

The next few evening will be spent painting BSM with "blue" and scribing lines on it!!! I am not too good with a hacksaw and blades seem to break at a great rate...

regards

ralph

[cabbage]

Well today and yesterday have been spent wrangling with wires... I hold fast to the saying that any wire cut to exact length is 1cm too short!!! My speed control system (as such) is based on a circuit from the book "Model Railway Electronics" by Roger Amos (I have the 2nd Edition). However I have adapted his "PWayMan Circuit" to my own ends. His circuit uses the 50Hz half wave recitfied DC from the mains as his sine wave to "chop" rather than chopping a square wave -this gives Pulse Width Amplitude Modulation. I on the other hand produce my own sine wave -and thus a variable frequency. What I do is use the same Potentiometer shaft (a double gang) to alter the Mark Space Ratio of the "chop" whilst at the same time increasing the frequency. A little soldering / fiddling with a collection of fixed value resistors in series and I can tune the Mark Space Ratio to the slope of the rise in frequency. Lower frequency =more torque. Higher frequency =better battery life)

What I am about to say now I cannot prove -however I do know it to be valid!!!

For some reason a 5 pole motor is the lowest number of poles that you can successfully use a PWAM system with for smoothness. If you try a 3 pole motor -you would be better to just use a simple supply. If someone could like to come up with the reason -then I would be delighted to know(?)

How my control system works is this: Each motor has its controller capable of 3 Amperes each -fed from a 12 Volt source. They share a common connection to the dual gang potentiometer that alters the MSR and frequency. The change of direction is controlled by a Solid State Relay (apply a ground to pin 7!)

The control interlocks are not even at the "scribbles and doodles" stage -so at this time it would be possible to make the system flip from Full Fwd to Full Rev. What has got to be done is to ensure that the system waits until the frequency of the PWAM drops to Zero -before it starts to ramp it up again.

Time for mental diversion -while the subconcious works it out!!!

regards

ralph

[cabbage]

Well after a hard day at the desktop.... I have had to ship my lathe back for repairs -something is wildly amiss and I cannot work out what(!) This has left me nothing to do but sort through my collection of "primitives" to turn into functioning parts of my chassis. So, I looked at them took a deep breath and dived into the two chassis rails. The first thing was to make them "true" to themselves. I wrapped a length of parcel tape around one end and drew a square line with the try square at the other. Deep breath, saw -broke the blade... Thee blades later and I had 4 square ends. The next job is to make a matched pair of them. I duly clamped with my "moles" and marked out two holes and drilled through both pieces. After having grunted two 3mm nuts and bolts through the holes, (this is normally enough to lock the two plates in place), I set out marking up the frame plates for the horns.



I know the preview shot is a little squinty -but you should be able to see the row of 3mm drill holes that form the top of each guide slot. The two holes either side of the central slot are for the 5mm transverse bolts that couple the chassis frame plates to the "spine" holding the motors and Quill drives. The theory is that simply undoing the 4 bolts will allow me to work on the system as it "should" simply drop out.

Always design your model to be easy to do repair work on!!!

regards

ralph

[cabbage]

Well at the end of "Fantastic Friday" -I seem to have a pair of chassis frames(?) The shape for the bogie holes was initially made on graph paper and then stuck to a piece of ABS scrap -which was then scissored to shape. I scratched around it and then started my pillar drill work.

Here you can see the scratched curves and the line of 3mm holes.



The curves were removed by the simple method of sawing 4 slots from the edge to the curve and then clamping them in a set of "moles" and snapping them off. The resulting shark tooth edge will be treated to the grinder. Here are the two plates simply held together by a couple of bolts. The plates will be 9cm apart -so they will sit wider than this.



The next pieces to be made are the bogie mounting plates -with the triangular cutouts for the cables and the slots for the traverse of the Bissel Bogie, (and "the mousetrap" that will lock the arm of the Bissel Bogie in position for moving on the straight)....

regards

ralph

[cabbage]

Well shortly before retiring to my work with my mug of tea and digestives -I will bring you up to date with the progress. Today I have completed the Bogie mounting plates and you can see them positioned here with the aid of some Blu-Tack....



The next step is to start work on the bogie side plates themselves. Once they are complete I will be able to see if my maths was correct and I have room for them to move side to side without them clashing on the frame plates...

regards

ralph