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On 05/04/2021 at 14:45, oily said:

Can I ask a really basic maybe stupid question as I'm trying an experiment to add synchronised sound to a loco.

 

How many chuffs would a Midland Compound do per driver revolution?

 

Oli

 

I was reminded of this question (and the various helpful answers from Nick, Andy and others with sound clips) when an elderly neighbour lent me his copy of "British Railways for Boys" by Cecil J Allen, written in 1949. In "Making and Using the Steam", it says: 'It is easy to distinguish a three-cylinder locomotive when it is at work, because there are six exhaust beats or "puffs" for every revolution of the driving wheels, instead of the more usual four. But with four-cylinder engines, it is customary to arrange the four cranks at right-angles, so that the puffs are thrown out in pairs, and there is no distinction between the puffing of a four-cylinder engine so arranged and a two-cylinder locomotive. One special three-cylinder arrangement is that of the well-known "Midland compounds" of the London Midland Region; they are so-called because the steam is carried through two stages of expansion, first in a single "high-pressure" inside cylinder taking steam direct from the boiler, and then in two outside "low-pressure" cylinders before it is thrown out of the chimney as exhaust. These compounds puff in just the same way as an ordinary two-cylinder locomotive.'

 

So the same conclusion as reached by m'learned friends earlier in the thread, but nice to have it on the authority of Mr. Allen as well.

 

regards

Graham

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A question for those who have built an association 4F and compared it with the current offering from GraFar. How do they compare? Would I be better off getting an N 4F and converting it or is the association kit the better option? 

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2 hours ago, A. Bastow said:

A question for those who have built an association 4F and compared it with the current offering from GraFar. How do they compare? Would I be better off getting an N 4F and converting it or is the association kit the better option? 

 

Only you know which is the better option. It all depends what you want and what you value.

 

The Farish model is well detailed and quick to convert. It is however to 1:148 has some compromise in splasher size etc and only allows you to model a limited range of 4Fs.  A new tender chassis is a good idea to improve pick up, but it will remain a bit weedy as far as pulling power is concerned.

 

The Raithby model allows you to model any beaded Fowler tendered 4F with beaded or plain splashers and LH or RH drive on the loco. It is to 1:152 and regardless of which chassis you use can be made into a reliable and strong hauler. However the original etch is from the mid-80s,  will take a while to build and depending on your current level of skill may be tricky to build to the standard you require. This is particularly true of the loco body. It can however be made into a lovely model and etched metal always has a fineness which moulded plastic lacks particularly when it comes to tender sides etc. 

 

Simon

 

 

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2 hours ago, 65179 said:

The Raithby model allows you to model any beaded Fowler tendered 4F with beaded or plain splashers and LH or RH drive on the loco. It is to 1:152 and regardless of which chassis you use can be made into a reliable and strong hauler. However the original etch is from the mid-80s, 

 

A few years ago the Raithby 4F was the basis of the association chassis workshop. A supplementary etch was supplied to fix issues with the tender.

 

Is this etch supplied with the kits from the association shop? I git he impression they had to be procured separately by the organiser(s).

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16 minutes ago, Crosland said:

 

A few years ago the Raithby 4F was the basis of the association chassis workshop. A supplementary etch was supplied to fix issues with the tender.

 

Is this etch supplied with the kits from the association shop? I git he impression they had to be procured separately by the organiser(s).

 

The etch to fix the width issues with the tender body is supplied with the etch from the Association  shop. There is also a separate chassis etch available for loco and tender with cantilever gearbox, chassis jig etc like the Farish replacement chassis for other prototypes.

 

Simon

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6 hours ago, A. Bastow said:

A question for those who have built an association 4F and compared it with the current offering from GraFar. How do they compare? Would I be better off getting an N 4F and converting it or is the association kit the better option? 

 

Simons answer above pretty much sums it up. The Raithby 4F is a lot more work but makes up into a really nice model. I have a couple of examples of both and run them happily alongside each other but the Raithby examples get rostered for the heavier turns.

 

Jerry

 

135967476_4Fs_11.jpg.a2766b0906a4d2c26a939625edc5d92f.jpg

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Another point to consider is that, if you can find one, there is the option of the Johnson 3,250 tender with the Farish. Not sure whether there is a current etch for one in 2mm as per Jerry's example. Don't think the Raithby one covers it? 

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12 minutes ago, Izzy said:

Another point to consider is that, if you can find one, there is the option of the Johnson 3,250 tender with the Farish. Not sure whether there is a current etch for one in 2mm as per Jerry's example. Don't think the Raithby one covers it? 

 

No, the Raithby etch just does the two main sorts of beaded Fowler tender (with and without coal doors).

 

Simon

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12 hours ago, Izzy said:

Another point to consider is that, if you can find one, there is the option of the Johnson 3,250 tender with the Farish. Not sure whether there is a current etch for one in 2mm as per Jerry's example. Don't think the Raithby one covers it? 

I have produced an etch for a Johnson 3,250 gal tender, designed specifically for the Midland Railway 483 class. I can't remember exactly what the differences would be for one attached to the 4F but I think it mainly relates to the height of the step at the front of the tender.

 

Here's a pic of one under construction.

 

399225458_Johnsontender(27).JPG.5d14ef9080ed70a2c8941eb8a953de5e.JPG

 

Nigel Hunt

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43 minutes ago, -missy- said:

I am doing some lobster pots. Any ideas on what I could use for the netting?

Some fine gauze or nylon stocking?

 

Jim

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It’d be stupidly expensive for what you want to use it for but I got some EMC mesh that is .001” blackened copper wire fixed in a square grid spaced at 100 openings an inch at work for a current project. I don’t think I ever saw any mesh so fine as this before. 

 

It’s a Parker Chomerics product. Maybe you can convince a rep to send a sample or get some offcuts from somewhere.  

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On 01/07/2021 at 18:30, -missy- said:

Hi.

 

I am doing some lobster pots. Any ideas on what I could use for the netting?

 

image.png.1f8dc162444038ede6ea8ae194ef4856.png

 

 

 

 

I have some of this. If it looks OK, PM your snail mail address and I can pop some in an envelope for you. Probably enough for a few dozen pots that size.

 

fine_mesh.jpg.873554de2e142857809a94bc29b10996.jpg

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A question on Association worm gear sets...

 

I've recently given some attention to my long-running and so far unsuccessful Association Farish Pannier replacement chassis - I bought all the bits for this some years ago and have made sporadic progress at intervals since then. What I've got so far doesn't work too well so I've decided to revisit it with some of the video-wisdom of Dr Mitchell and try to get things working a bit more smoothly, but unfortunately I can't remember where I started and didn't make notes...

 

The problem is that I don't know exactly what the worm gear set is. The gear is a brass 30T but I'm not sure of its bore - the current Association Shop 3 list only lists 1/8" worm sets but this appears to be 3.0mm bore - a 3.0mm drill fits it easily, and a 3.1mm doesn't fit at all. It's ages since I worked on this but I have it on a stepped muff which seems to be a sliding fit - I have another seemingly identical and unused muff which is 3.2mm diameter over the longer part. My assumption is that I've brutally reduced the muff diameter by forcing a 3.0mm gear onto a 3.2mm (1/8") muff. 

 

Can anyone confirm what the gear is? It's definitely a worm gear (concave teeth) and definitely has 30 teeth (I've counted twice). It appears to be the same as the current 30:1 1/8" set but with a 3.0mm bore. I'm aware there have problems with gear supply in recent years so maybe this is a now unavailable metric set? 

 

They say there's no such thing as a stupid question, but I'm not so sure. 

 

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The worm sets we got from KKPMO in Poland had a 3.0mm bore. Yours must be one of these.

The current gears have 3.2mm (1/8") bore like the Ultrascale ones the Association supplied even longer ago.

The last batch we had from Poland were problematic in that the skew was cut the wrong way so they didn't mesh at all with the worms!

As long as you haven't got one of those(!), you need to fit it to a 3-102b metric gear muff.

The stepped muffs (3-102a like your unused one) are designed to take a 1/8" worm wheel and a 3.0mm spur gear. You can't fit a metric worm wheel to them, since the 3.0mm section is on the short section. I don't think you'd be able to fit a 3.0mm bore gear onto a 1/8" muff without noticing, however brutal you were!

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15 minutes ago, Nick Mitchell said:

The worm sets we got from KKPMO in Poland had a 3.0mm bore. Yours must be one of these.

The current gears have 3.2mm (1/8") bore like the Ultrascale ones the Association supplied even longer ago.

The last batch we had from Poland were problematic in that the skew was cut the wrong way so they didn't mesh at all with the worms!

As long as you haven't got one of those(!), you need to fit it to a 3-102b metric gear muff.

The stepped muffs (3-102a like your unused one) are designed to take a 1/8" worm wheel and a 3.0mm spur gear. You can't fit a metric worm wheel to them, since the 3.0mm section is on the short section. I don't think you'd be able to fit a 3.0mm bore gear onto a 1/8" muff without noticing, however brutal you were!

Thanks for the very prompt reply Nick - that sounds about right. I've checked the skew and the worm and wheel definitely mesh OK. I suspect that what I did was order the wrong muffs then attempt to turn one down to 3.0mm, made a pig's ear of it and it's ended up as a sliding fit.

 

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21 hours ago, Ian Morgan said:

 

 

I have some of this. If it looks OK, PM your snail mail address and I can pop some in an envelope for you. Probably enough for a few dozen pots that size.

 

fine_mesh.jpg.873554de2e142857809a94bc29b10996.jpg

 

Thank you Ian, that is very kind but I think I have a solution. Out of interest, what is it?

 

Julia.

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Can anyone suggest a good source of thin (i.e. sub-1mm) double-sided PCB please?

 

The standard stuff seems to be 1.6mm (too thick, and I've got loads of it anyway...) and RS Components do a number in 0.8mm which would be good, but is this the thinnest available?

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26 minutes ago, chrisveitch said:

Can anyone suggest a good source of thin (i.e. sub-1mm) double-sided PCB please?

 

The standard stuff seems to be 1.6mm (too thick, and I've got loads of it anyway...) and RS Components do a number in 0.8mm which would be good, but is this the thinnest available?

 

Eileens do some (or they did) I have got some down to 0.3mm

 

Julia :)

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7 hours ago, chrisveitch said:

Can anyone suggest a good source of thin (i.e. sub-1mm) double-sided PCB please?

 

The standard stuff seems to be 1.6mm (too thick, and I've got loads of it anyway...) and RS Components do a number in 0.8mm which would be good, but is this the thinnest available?

Me. I have a lot of 0.25mm and some other similar thicknesses, free of charge. If you are interested send me a PM specifying what you want.

 

Nigel Hunt

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11 hours ago, Nig H said:

Me. I have a lot of 0.25mm and some other similar thicknesses, free of charge. If you are interested send me a PM specifying what you want.

 

Nigel Hunt

Many thanks - PM sent.

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  • 2 weeks later...

Another query about wagon bits.

 

I am looking at doing a batch of the Associations  2-566 Van Body (No Roof): BR Standard Box Van Dia 1/208, 1/203.

 

I can see the roofs listed, but what chassis ?

 

Buffers, 2-075 should be correct as these will be built as fitted wagons, except, I can't see them listed. Would 2-076 be better.

 

Regards

 

Ian

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