Copenhagen Fields & TFW’s workshop

This forum is for the discussion of railway modelling of the LNER and its constituent companies.

Moderators: 52D, Tom F, Rlangham, Atlantic 3279, Blink Bonny, Saint Johnstoun, richard

Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

The Skittle Alley has made some progress with the coupling rods now made.
Image

The roughed out rods were finished by planing the flutes using a specially ground gramophone needle in a marking gauge using a brass plate as a guide.
Image
https://youtu.be/zhQZFlFfQ14

Next stage will probably be the drive train onto the back axle.

https://youtube.com/shorts/cX5inECDXO4?feature=share

Tim
Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

The gear head for the Raven NER 4-6-2 has been made from a 6x10x10mm block of brass. This was initially an interference fit between the frames to help determine the worm and worm-wheel mesh.
Image
The frames and block were then drilled for 14BA to hold this position.
Image
The gap next to the opposite frame is just visible behind the shaft. The wheels are not at the final back to back measurement; allowing easy adjustment at this stage. The worm is twice as long as it needs to be and will be trimmed and a thrust washer placed next to the bearing.
The non-bolted side was trimmed back on some sharp Vallorbe files to be clear of the opposite frame (for electrical isolation).
https://youtube.com/shorts/5fE4LGXSAaA?feature=share
The edges of the block were lightly bevelled - it’s engineering, not clockmaking where the edges should be sharp enough to cut…

Tim
Last edited by Tim Watson on Mon Dec 12, 2022 12:53 am, edited 1 time in total.
User avatar
Atlantic 3279
LNER A4 4-6-2 'Streak'
Posts: 6523
Joined: Fri Jun 26, 2009 9:51 am
Location: 2850, 245

Re: Copenhagen Fields & TFW’s workshop

Post by Atlantic 3279 »

I enjoy seeing the hand-cut / hand-made engineering in 2mm scale - much finer than anything I hope (or intend) to ever struggle with. Most impressive.
Most subjects, models and techniques covered in this thread are now listed in various categories on page1

Dec. 2018: Almost all images that disappeared from my own thread following loss of free remote hosting are now restored.
Hatfield Shed
LNER A4 4-6-2 'Streak'
Posts: 1661
Joined: Fri Dec 23, 2011 3:34 pm

Re: Copenhagen Fields & TFW’s workshop

Post by Hatfield Shed »

Bis!

I very much look forward to seeing this loco running, at some future opportunity of viewing Copenhagen Fields.
Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

NER green is pretty bright!
Image
Rummaging through a tobacco tin, I very luckily found some 12 spoke 3’9” wheels that Denys Brownlee had roughed out 30+ years ago, these were correct for the very conspicuous trailing radial truck and just needed finish turning. The front bogie wheels will have to be hand made. The basic chassis should be running soon. 

Tim
Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

The gear head and loco universal joint were finished a few days ago; the worm shortened and thrust washers placed at each end. 
Image
The cut down teeth on the UJ cover is from an old eccentric Association gear.  It makes it easier to turn the shaft by hand.
Image
The brake hangers on the frames were made from pivot steel soldered through holes into place with a very effective solder and flux.
Image
The flux is a very corrosive oil and so the chassis was degreased and then boiled in water for 5minutes.
The next stage was to complete the frame spacer at the front end of the loco; the notches inside the frames are to take the nuts of the studs that will hold the cylinders in place. 
Image
The frames were chemically blacked: much better than painting.  The drive from the tender needed a chassis, so this was cut out of two layers of phosphor bronze strip sweated together. 
Image
Image
The frames were clamped up onto the PCB spacer, held in place by an orthodontic arch expander, and the siting rods (as usual) helped in alignment before soldering.
Image
The Tram Fabrik motor obviously needed the other half of the UJ and so this was also incorporated into a flywheel. This was started on the big lathe in the garage: namely the main body, the smaller diameter UJ section and the 2mm diameter counter bore. 
Image
It was then taken into the garret workshop and finished off by drilling the shaft hole (0.9mm with a short section at 1.0mm) mounting the UJ section in a collet in the watchmakers lathe (it’s also much warmer upstairs)
Image 
The hole was then taken up in size with a tapered broach until it just slipped onto the motor shaft to within a millimetre of the final position. The UJ slot was cut with a piercing saw and then finished with a slitting file, whilst holding it in a mandrel and a stepped chuck.
Image
Image
The motor itself is mounted in a brass collar with two 14BA studs silver soldered to it. These are then bolted through the PCB spacer. 
Image
The flywheel was gently pushed home with some Loctite 601 on the shaft. The whole assembly easily fits into the tender: it could have had a bigger flywheel, but that would have sat quite a long way forwards and not too good as a side load on the front bearing. 
Image
The two PCB pads at each end of the tender frames are Araldited in place and slightly raised to keep the body from shorting out the split chassis. 
Anyone who has got this far deserves a medal!

Tim

 
Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

https://youtu.be/i16nnr6LEfk
It works!
Image
Merry Christmas everyone.

Tim
mick b
LNER A4 4-6-2 'Streak'
Posts: 3726
Joined: Tue May 30, 2006 4:43 pm

Re: Copenhagen Fields & TFW’s workshop

Post by mick b »

Excellent work !!


Merry Xmas !!
User avatar
Atlantic 3279
LNER A4 4-6-2 'Streak'
Posts: 6523
Joined: Fri Jun 26, 2009 9:51 am
Location: 2850, 245

Re: Copenhagen Fields & TFW’s workshop

Post by Atlantic 3279 »

Amazing. What's the exact form of the shaft that connects the two U/Js please?
Most subjects, models and techniques covered in this thread are now listed in various categories on page1

Dec. 2018: Almost all images that disappeared from my own thread following loss of free remote hosting are now restored.
Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

It is effectively a ? bent at each end of the 10thou spring steel wire, but with a closed loop. There is a shroud around each female half of the UJ to stop the loop moving sideways. These are really quite strong and virtually invisible when running as they are never completely true running.
Image
Tim
User avatar
Atlantic 3279
LNER A4 4-6-2 'Streak'
Posts: 6523
Joined: Fri Jun 26, 2009 9:51 am
Location: 2850, 245

Re: Copenhagen Fields & TFW’s workshop

Post by Atlantic 3279 »

Thank you.

Another stupid question: Do the loops at both ends lie as nearly as possible in the same plane, or are they arranged at 90 degrees? Does it matter?
Most subjects, models and techniques covered in this thread are now listed in various categories on page1

Dec. 2018: Almost all images that disappeared from my own thread following loss of free remote hosting are now restored.
User avatar
kimballthurlow
GCR D11 4-4-0 'Improved Director'
Posts: 432
Joined: Wed Apr 29, 2009 10:58 am
Location: Brisbane, Australia
Contact:

Re: Copenhagen Fields & TFW’s workshop

Post by kimballthurlow »

Thank you Tim, that is really fascinating work.
I am sorry but I do not know what the term UJ means?

Kimball in Brisbane
65447
LNER A4 4-6-2 'Streak'
Posts: 1739
Joined: Fri Oct 19, 2007 2:44 pm
Location: Overlooking the GEML

Re: Copenhagen Fields & TFW’s workshop

Post by 65447 »

kimballthurlow wrote: Mon Dec 26, 2022 7:47 am Thank you Tim, that is really fascinating work.
I am sorry but I do not know what the term UJ means?

Kimball in Brisbane
UJ = Universal Joint - one which allows the parts of the shaft to be at differing angles to each other whilst still transferring the rotational movement.
User avatar
kimballthurlow
GCR D11 4-4-0 'Improved Director'
Posts: 432
Joined: Wed Apr 29, 2009 10:58 am
Location: Brisbane, Australia
Contact:

Re: Copenhagen Fields & TFW’s workshop

Post by kimballthurlow »

65447 wrote: Mon Dec 26, 2022 10:21 am .....
UJ = Universal Joint - one which allows the parts of the shaft to be at differing angles to each other whilst still transferring the rotational movement.
Thankyou 65447,
I had a feeling it was going to be so obvious as to make me look silly.
Anyway you offered a sublime explanation for the mechanics.

Kimball
Tim Watson
GER D14 4-4-0 'Claud Hamilton'
Posts: 305
Joined: Mon Oct 24, 2016 11:37 am

Re: Copenhagen Fields & TFW’s workshop

Post by Tim Watson »

Atlantic 3279 wrote: Sun Dec 25, 2022 9:56 pm Thank you.

Another stupid question: Do the loops at both ends lie as nearly as possible in the same plane, or are they arranged at 90 degrees? Does it matter?
There is never a silly question and it was remiss of me not to use the name in full before using the abbreviation. I don’t think orientation makes any difference. These ones are at 90 degrees to each other. Previous ones have been in line. I might make an in-line one to try the experiment on this engine.

Tim
Post Reply