Elmham Market in EM

James Spooner

Western Thunderer
Dave

Many thanks for your advice, and in particular for the help you gave me via a separate message; all much appreciated and it shows the value of a good forum such as this.

As a result of the advice, my current thinking is to lengthen the radius rod. It does seem to be the correct length already (if a trifle long, based on Dave’s measurements) and I think the slots that were milled into the frames to accept the motion bracket were cut in the wrong place. However, if I try to cut another pair of slots a couple of mm in front of the current set, I think I am likely to end up with a massive gouge in the frames and no real meat to hold the brackets in with. I might turn my attention to something else for a bit, to clear my head, then devise a way of stretching the radius rods.

Cheers

Nigel
 

James Spooner

Western Thunderer
I have been a bit distracted from the Ivatt recently. Last weekend a group of us worked on line side clearance on the Ffestiniog Railway (good fun and a good work out as well). The photo shows several of us removing trees that have the capability of bringing down the telegraph wires for the ETS system.

IMG_2808.jpeg

On my return I have been catching up on ‘stuff’ so it’s only this weekend that I have been able to turn my mind to the valve gear. At this point I must record my thanks to @Dave Holt and @dibateg for their help, advice and also etchings to get me through this stage. In the end I concluded that the principal issue was the slot in the frames to hold the motion bracket was in the wrong place (a point confirmed by Tony) so the logical thing to do was a bit of open heart surgery on the frames, which I did with my piercing saw.

IMG_5575.jpeg

Having moved the motion bracket forwards towards the cylinders things seemed to fall in place much better (unsurprisingly really I guess!). Reading the instructions carefully, there still didn’t seem to be any valve spindle or arrangement for holding the front end of the radius rod/top of combination lever in place so I have fudged that by cutting off the top of the combination lever and holding the spindle hole in place with a piece of 0.8mm brass wire. I will need to do the same for the front of the radius rod but can’t until I am sure of the location of the hole I need to drill for the wire (as the cylinders and motion bracket aren’t soldered in place yet). I have managed a trial assembly of the right hand valve gear and it seems to work OK. I’ll take the left hand assembly to the same stage then solder up the motion bracket and cylinders, keeping my fingers (metaphorically!) firmly crossed. The trial assembly of the right hand valve gear is in the photo below.

Nigel


IMG_5580.jpeg
 

James Spooner

Western Thunderer
Some more progress this evening. The driver’s side valve gear has been brought up to the same stage as the fireman’s. The cylinders have been tacked onto the smokebox saddle casting and the whole shebang trial assembled. There are one or two places where a bit more filing is needed to get a free running set of motion but I think it is progress.

Nigel

IMG_5585.jpeg
 

James Spooner

Western Thunderer
Nigel.
If it's not a silly question, what's that vertical bit attached to the back of the LHS cross head?
Dave.
Dave,

It is absolutely not as silly question. I have been puzzling over that myself but it is clearly an intended part of the nickel silver casting, rather than a piece of flash. As you have asked the question I will go through my photos of the Ivatts and see if I can find any clues. I may have to remove it.

Nigel
 

Dave Holt

Western Thunderer
I agree with Tony. Early Stanier locos were fitted with a vacuum pump below the slide-bars, GWR style. However, they were later removed and by Ivatt's time were not being fitted to new locos.
Sorry to say, it needs to come off.
Dave.
 

James Spooner

Western Thunderer
Well Tony @dibateg and Dave @Dave Holt as promised, the vacuum pump bracket, after an hour or so’s careful filing and use of the Dremel, has now been consigned to history. Many thanks both for pointing this out; much better at the construction stage than when it has all been finally assembled and painted!! Photo attached. Hopefully I will progress a bit further this evening!

Nigel

IMG_5588.jpeg
 

James Spooner

Western Thunderer
Taking our youngest son back to uni took up much of today but I have managed to progress the chassis. Balance weights are on the wheels OK. The pony truck was next. The first problem was the guard irons seemed to be missing. I took a quick look at the drawing and a works photo I have on the wall of 43070 and made up a pair of irons out of nickel silver sheet.

IMG_5605.jpeg

I then happened to glance at a photo of 43089 and it didn’t appear to have the same prominent guard irons that 43070 had. Browsing through my Sixsmith book of Ivatt 4MTs seemed to confirm that many of the class had a much flatter guard iron arrangement attached to the bottom of the pony truck.

IMG_5607.jpeg
Off came the original guard irons and a new one was fettled up out of more nickel silver sheet…

IMG_5606.jpeg
I am now at the stage of fitting the pony truck to the chassis but it is still fighting me. The cut out in the frames to take the pony wheel is in the wrong place so I have spent the last part of the evening filing the frames back. I think I might also trim the guard iron back a bit but will decide on that once it is pivoting properly.

Nigel
 

James Spooner

Western Thunderer
A bit of a frustrating session today. I took the Ivatt out to Elmham Market for a test in the real world and it kept stopping. I traced this to some sort of short so removed the large nickel silver balance weights on the central drivers and replaced them with 10thou black plasticard ones. I also trimmed back the frames around the pony a bit more and trimmed back the tails on the guard irons. Retest. Still not consistently working. By this stage I wasn’t sure where the short was so I took the pony truck off and reassembled the loco. Hey presto…
I have refitted the pony truck and slapped a thick coat of paint on anywhere around the frames where something might be touching and am currently waiting for it to dry before retesting. If I get another short I should be able to tell where it is as the paint will have been scraped off. Well, that’s the theory anyway!

Nigel
 

Dave Holt

Western Thunderer
It seems to run very well without the pony truck, Nigel. Perhaps the answer is to just leave it off?:))
I gather from the latest WHR Soc magazine that congratulations may be in order?
Dave.
 

James Spooner

Western Thunderer
It seems to run very well without the pony truck, Nigel. Perhaps the answer is to just leave it off?:))
I gather from the latest WHR Soc magazine that congratulations may be in order?
Dave.
Yes, tempting I must admit!! Further work last night has, I think, isolated the problem to the pony wheel touching the rear of the left hand cylinder on the tightest bends. The loco runs perfectly around the line facing the other direction with the pony truck on, so I will continue to investigate.

Thanks for your best wishes. I’m not sure whether it should be congratulations or commiserations, but it is certainly an honour to have been invited. The thing I was nervous about was my driving rules test, which we have to retake every three years, but I got an email last night confirming I had passed, which was a relief.

Nigel
 
Top