7 1/4" Bridget to Ken Swan design

[Deleted]

Jun 8, 2021 13:27:06 GMT jon38r80 said:

Definitely me!
I often dont understand Mr Scott's posts.

Young David does seem to speak in a foreign tongue sometimes...

Pete

[dscott]

I tend to follow on conversations from the previous person... I should quote more often.
It is Just how many things could you get to work on your locomotive like sanding, Water troughs, Even borrow an idea from the O and OO Boys and have a sound system in time with the wheels going round. Steam does not scale in sound very well and you have to make her work to get the best effects.

Strangely Jon my first 2 years were spent watching steam going through Watford. Being born in Bushey 1959 if only mum had used the camera properly. And Dad working for Kodak of all companys at the time. Then they moved North so I wouldn't be at School with George Michael!!!
Fate.

David and Lily.

[jordanleeds]

Jun 5, 2021 17:52:12 GMT rrmrd66 said:

Hi Jordanleeds

I have sent you a PM

Malcolm

Have replied

[jon38r80]

David
Small world,I lived in Ickenham, my father was in the film industry and often took rushes to Kodak in Denham I think it was.

[Deleted]

Jun 9, 2021 17:07:44 GMT jon38r80 said:

David
Small world,I lived in Ickenham, my father was in the film industry and often took rushes to Kodak in Denham I think it was.

It's certainly a small world, I'm in Harrow which isn't far from either location. There used to be a large Kodak plant not far from Harrow & Wealdstone station where the infamous train crash occured in 1952. Not much left of the plant today, most has been flattened for housing. I'm only a couple of miles away in Kenton.

Pete

[uuu]

I went for a job a Kodak - didn't get it. But I quite fancied researching into the machines that cut the sprocket holes in film - like cutting cheesecake (stiff base with wobbly bit on top).

Wilf

[rrmrd66]

Morning everybody

Further to my request for Ken Swan's construction notes in ME I have received help from several forum members, for which thanks.

One further elusive article on "Valve Gear" apparently was published in:

Year 1972 Volume 138 Issue 3436 Page 233.

Anybody out there got a copy who could scan/copy the pages for me? PM me if you can help.

Thanks

Malcolm

[rrmrd66]

Hi everybody

ref: ME Year 1972 Volume 138 Issue 3436 Page 233.

All sorted. Copy obtained

Thanks

Malcolm

[chris vine]

Hi Malcolm,

While I am sure you can improve on the valve events, in practice they work well.

When my Bridget was new (with no wear), you could notch up almost to mid gear. So the design cannot be far amiss...

Chris.

[Gary L]

Jun 19, 2021 20:25:24 GMT chris vine said:

Hi Malcolm,

While I am sure you can improve on the valve events, in practice they work well.

When my Bridget was new (with no wear), you could notch up almost to mid gear. So the design cannot be far amiss...

Chris.

Same here. And with the care he took with the rest of the drawings, I can’t see Ken doing less than best with the valve gear.

Gary

[dscott]

All I can see as an improvement is to move the valve over towards the middle and I have machined the bits so that I can.
I am doing the same on the Fowler Complex with now Bigger Lumps for cylinders making her look more Narrow Gauge.

Typical of this house? Yes we got a bunged out pile of early M. E. and just looked through them as it said 1972 and you guessed it 3435 and 3437 and an original Jan 1 1903. 3436 MISSING!!!! All the luck in finding things lay in today's workshop and the Outside jaws for the griptrue via Model Engineer website for £25 fitted like 3 gloves.

David and Lily.

Lily opened the package and cleaned the chuck before I fitted them.

[chiptim]

Hi Malcolm,

I haven't built Bridget, but built a Jesse. On the assumption of similarities in the following:

Valve Rod Guide - specified as 1/8" MS bent to shape. I found these don't offer great support due to their flexibility and have seen various improvements by Googling Jesse images. Perhaps machine from solid?

Superheater Manifold - Specified as 3 individual manifolds held together with pillars and connected via 2 copper tubes. I found this very tricky to make steam-tight and think you'd be better off machining as much as possible from
the thick wall GM tube (or is it hollow round?) that is available. Mine fell apart attempting to reflow and I burnt the threads. Still waiting to rebuild when I resume ME.

Regards Tim

[dscott]

On the Twin Sisters there is a substantial bracket and bearing surface for this.
I re drew one over a month ago for the emerging 2F Dock Tank. Now to 1 1/16" to the foot.
Just a bit more space and a Jinty Boiler trimmed at the firebox.
This is bolted to the frame which in a way is easier to line up.

David and Lily.

[rrmrd66]

Hi Tim (chiptim)

Thanks for the heads up.

I will check it out in due course. Chris Vine has also pointed out a potential problem area earlier in valve actuation on in this thread.

Regards

Malcolm

[chris vine]

Yes, the original Hawthorn Leslie engines had the offset to the side valve drive.
It was supported in guide just like Ken Swan shows it. However, the drive into the valve chest should be in the centre - there was an adjustable collar which took the drive to the centre and gave adjustment to the valve.
I asked Ken about this many years ago and he admitted that he had misunderstood the arrangement on the original.

Apart from this it is a lovely design and works really well.
You could either incorporate the step over to bring the valve spindle to the centre, or just make double sure that the valve spindle won't rack loose by silver soldering it into the buckle.

All best
Chris.

[arch1947]

Hi, I have a Bridget by Ken Swan, unfortunately in pieces at the moment, but that is another story. One problem I found with the loco I bought was that the rocking grate often didn't. When I pulled the boiler it became obvious that the geometry of the operating levers was not optimal. In the closed position the levers and associated cranks had very little mechanical advantage and essentially locked up. Resetting the cranks etc. solved the problem. Worth checking.
Cheers,
Arch

[Gary L]

Jun 25, 2021 1:08:20 GMT arch1947 said:

Hi, I have a Bridget by Ken Swan, unfortunately in pieces at the moment, but that is another story. One problem I found with the loco I bought was that the rocking grate often didn't. When I pulled the boiler it became obvious that the geometry of the operating levers was not optimal. In the closed position the levers and associated cranks had very little mechanical advantage and essentially locked up. Resetting the cranks etc. solved the problem. Worth checking.
Cheers,
Arch

Hi Arch
Did you check it against the drawing?
Gary