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Cleminson chassis drawing

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I've been googling for a couple of days, but can't find a diagram of how a Cleminson 6 wheel chassis works. Can anyone point me in the direction of one? If there isn't an online one, could anyone scan me one?

 

thanks

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There was an article and drawings in 'The Engineer' Feb 15th 1878 which were reproduced in 'Branch Line to Southwold' [Mitchell and Smith] Middleton Press 1984 ISBN 0906520150 and also in the magazine of the 7mm Narrow Gauge Association, Narrow Lines no 105 June 1997

 

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Mike

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There was an article and drawings in 'The Engineer' Feb 15th 1878

Mike

Good to see that you are up-to date with your reading, Mike ! :P

 

There was (IIRC) a short series on modelling this type of chassis in the modelling press in the 60's. Most likely in the M R Constructor. Don't have an index to hand, perhaps others can help?

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Good to see that you are up-to date with your reading, Mike ! :P

I may have a few grey hairs but I'm not that old. :D

 

I found the details purely by chance earlier today when I was sorting out my collection of 'Narrow Lines' into a bigger storage box. I just happened to see that the front cover of no 105 mentioned Cleminson, which turned out to be a reprint of the information in 'Branch Line to Southwold', which in turn was a reproduction of the article from 'The Engineer' in 1878. Another pure fluke is that a layout article in NL105 by Rowland Binns mentions that the coaches shown on his layout use the Cleminson system and were described in 'Narrow Lines' no 59 Oct 1989. Rowland's article has drawings and photographs of how he made the system work. This also refers to an article in Railway Modeller Feb 1989 showing a model of the Festiniog Cleminson wagon. I must look at the Mickleover Club library and see if we have a copy of that.

 

I have since done a Google search on 'Cleminson 1878' to see if that was available on-line which has led me to the National Library of Australia where you can search and view copies of The Mercury newspaper published in Hobart Tasmania. The first article 6 Feb 1878 introduces the system as possibly being suitable for the Tasmania Railway, followed by a letter from Cleminson on 24 May 1878 explaining more about his developments. This resulted in a response on 27 May from Thomas Midelton who was the Engineer and Locomotive Superintendant of Tasmanian Railways and on 15 Oct 1878 they published a series of letters from Cleminson and a Mr T Claxton Fidler who claims to be the original inventor. This then resulted in a very long response from Midelton on 21 Oct - but life's too short to read it all :rolleyes:

 

Isn't the Internet a wonderful tool for research like this - how else could I have found all this original correspondence in just a few minutes.

 

Mike

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I've joined this group because I found the discussion on Cleminson by an online search. I've been toying with the idea of seriously researching Cleminson the man, and his patent radial axle system for a while - I'm a member of the Welsh Highland Railway Heritage group and its predecessor the North Wales Narrow Gauge railway had three Cleminson coaches, and he was for a time the railway's engineer. Anyway, I have recently acquired a copy of the original patent documents, which include a detailed drawing of how it works. Anyone can order a copy of old patents from the Intellectual property office in Cardiff. It's best to phone - 08459 500505. They were not particularly expensive, I forget how much but under £10. I haven't a scanner, but I don't photographing it - I assume it must be out of copyright.

 

I had also found the fascinating correspondence available online from the Hobart Mercury that Don B mentions and, yes, isn't online searching amazing!

 

Another source of drawings is Edouard Vignes book "A Technical Study of the Festiniog & Other Narrow-Gauge Railways" 1878. I see that "print on demand" copies of the original French version are orderable at about £10, but there is an out of print translation by Don Boreham around second hand at a price if you can find it. A drawing of a cleminson chassis taken from this book was used in the endpapers of Boyd's history of the Festiniog Railway, or at least it was in the first edition, I'm not sure if it has appeared in all the later ones.

 

Finally, if anyone knows of any sources of information on Cleminson, the man or his work, other than those already mentioned in this thread I would be very pleased to know of them

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I've joined this group because I found the discussion on Cleminson by an online search. I've been toying with the idea of seriously researching Cleminson the man, and his patent radial axle system for a while - I'm a member of the Welsh Highland Railway Heritage group and its predecessor the North Wales Narrow Gauge railway had three Cleminson coaches, and he was for a time the railway's engineer. Anyway, I have recently acquired a copy of the original patent documents, which include a detailed drawing of how it works. Anyone can order a copy of old patents from the Intellectual property office in Cardiff. It's best to phone - 08459 500505. They were not particularly expensive, I forget how much but under £10. I haven't a scanner, but I don't photographing it - I assume it must be out of copyright.

 

I had also found the fascinating correspondence available online from the Hobart Mercury that Don B mentions and, yes, isn't online searching amazing!

 

Another source of drawings is Edouard Vignes book "A Technical Study of the Festiniog & Other Narrow-Gauge Railways" 1878. I see that "print on demand" copies of the original French version are orderable at about £10, but there is an out of print translation by Don Boreham around second hand at a price if you can find it. A drawing of a cleminson chassis taken from this book was used in the endpapers of Boyd's history of the Festiniog Railway, or at least it was in the first edition, I'm not sure if it has appeared in all the later ones.

 

Finally, if anyone knows of any sources of information on Cleminson, the man or his work, other than those already mentioned in this thread I would be very pleased to know of them

 

If you're interested in the North Wales Narrow Gauge Cleminson coaches this may interest you. If you are in Porthmadoc over the early spring bank holiday weekend I will have the model with me on my stand at the Narrow Gauge Model Railway Exhibition in the Ganolfen opposite the WHR Heritage Station. If you are likely to be too busy during the day and are interested arrange to meet me Saturday night for a look. Pictures below to whet your appetite! This is an 0-16.5 model and it will traverse 19 inch radius curves. Please excuse the camera shake!! attachment=27706:100_0184.jpg]post-6862-126861049857_thumb.jpgpost-6862-126861053826_thumb.jpgpost-6862-126861057411_thumb.jpgpost-6862-126861060662_thumb.jpg

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In the Middleton Press 'Branchlines to Southwold there is a photo (no.6) of a Cleminson unit with no body on it which I found very useful for building my model. The following pages have the reprint of the1878 article with its diagrams and the page after that has a straight, side on a picture of a 'MOY' Cleminson coal wagon which whilst not ever so clear will yield more details when looked at closely, such as brakes on the centre wheels only.

 

The vehicle not to look at is the Festiniog 'Cleminson' coal wagon as it is an early version and lacks the important double hinged link between the trucks.

 

If you look on my photo's of the model floor you can see the relative movements of the two pins in the link by the scratches in the paint, the inner ones staight and the outer ones curved, and hence why the link is important.

 

The Manx Northern Railway on the Isle of Man also had some Cleminson 6 wheel coaches and one of those is still in existance in a museum over there. I seem to recall looking at some photo's of those as well in books on the islands railways whilst researching for the model, perhaps google might help here as well.

 

Hope this all helps a little

 

Phil T.

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I've been googling for a couple of days, but can't find a diagram of how a Cleminson 6 wheel chassis works. Can anyone point me in the direction of one? If there isn't an online one, could anyone scan me one?

 

thanks

 

Another excellent source is the book "The Manx Northern Railway" by Hendry and Hendry, Hillside Publishing. Contains scale drawings of the MNR Cleminson coaches, including the underframes, and a good selection pf photographs.

By the way, the photo of a Cleminson underframe in "Branch Line to Southwold" is actually one of the Manx coaches!

 

I will dig out my references later, and the photos of my models of the Manx coaches.

 

Cheers,

Dave.T

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Following on from my last message, the Manx Northern book I refered to is ISBN 9505933 2 X. It was published in 1980 and is I guess long out of print. It it does appear secondhand from time to time, and is worth getting for the rolling stock drawings alone.

 

Back to Cleminsons, I've built several models based on the Manx Northern coaches. My first one, shown in the first two pictures, had the underframe trucks built to scale from brass sections. They're a bit on the narrow side, but this is a 16.5 version, rahter than the corect 21mm gauge. Anyway, narrower trucks means greater lateral swing, means tighter curves can be negotiated.

 

Its shown in the first two pictures, minus its cosmetic spring/axlebox detail. Instead of the expanding link at the pivot point between the trucks, I substituted a simple rod-in-hole telescopic joint. As it was a brake coach I added the brake rodding as well.

 

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Once I realised that little of this was visible when running on a layout, I developed a much simpler version, but still with the same functionality, for the rest of the coaches.

I think the photos are fairly self-explanatory. What this version suffered from was a lack of weight in the trucks, compared to the solid brass version, hence the addition of slabs of lead. The spring and axlebox detail is a plastic moulding, by Slater's from their 0-Gauge GWR coach kits.

 

Hope this help,

Dave.T

 

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I thought that a true Cleminson bogie was pivoted between the end axles and the centre axles. The idea being that the sideplay required by the curve is not thus taken up by only the centre axle - the outer ones would move in the oppisite direction as well. Such a system would get much more movement so would be able to go around radically tighter curves.

 

Certainly, this is how the brassmasters one works:

 

post-7769-127543115225_thumb.jpg

 

post-7769-12754308921_thumb.jpg

 

The pivot is approximately 1/3 of the distance between the outer axle and the middle axle. It works well too.

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I thought that a true Cleminson bogie was pivoted between the end axles and the centre axles. The idea being that the sideplay required by the curve is not thus taken up by only the centre axle - the outer ones would move in the oppisite direction as well. Such a system would get much more movement so would be able to go around radically tighter curves.

 

Certainly, this is how the brassmasters one works:

 

post-7769-127543115225_thumb.jpg

 

post-7769-12754308921_thumb.jpg

 

The pivot is approximately 1/3 of the distance between the outer axle and the middle axle. It works well too.

 

It may be the way the brassmasters one works, and as you note it will go round tighter curves with less displacement of the centre axle however the true "Cleminson patent" chassis has the outer trucks pivotted above their axles.

 

The real problem is that over the years any 6 wheel articulated railway vehicle chassis has been described as a "Cleminson " and in reality only one particular patented design is truly the Cleminson patent system, the others should be described simply as articulated or radial chassis.

 

The one under my NWNGR coach in the photo's is the true Cleminson design, I spent a good while researching it before I built it. It was built purely to find out whether it would work scaled down and just to see if I could do it in 7mm/1ft . The answer in both cases was yes, but in model form it needs a fair amount of vertical movement in the centre truck even with well laid track (which mine wasn't!) and it would work better and go round tighter curves using true scale 14mm. gauge rather than my16.5mm. gauge track.

 

Phil T.

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Has anyone fitted the Brassmasters version to D&S kits. I have some NER versions already built and they wont go around curves at all the centre wheel derails even with a large lump of lead underneath !!

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Has anyone fitted the Brassmasters version to D&S kits. I have some NER versions already built and they wont go around curves at all the centre wheel derails even with a large lump of lead underneath !!

 

Because the pivot point for the outer trucks is so far inboard from the axles it needs far more sideways force from the centre wheels to move them, this won't help keep them on the track. Even the true cleminson needs a fair amount of weight on the centre axle, as can be seen in the NWNGR coach photo's, and this with the most favourable leverage.

 

It may be worth pointing out that the cleminson design keeps the axles as near as possible at 90 degrees to the track, moving the truck pivots nearer to the centre axle actually makes the outer axles oversteer which again puts more side loading on the centre wheels.

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Phil,

 

Interesting point about the differences on the chassis types.

 

I get the point about the leading/trailing wheels not being parallel with the rail head except on the true cleminson bogie. However, on any four wheeled vehicle this would be true as well and as the distance from the pivot to the axle on the brassmaster's cleminson (to look after my descriptions!) is quite small, this can not be a big issue? Certainly, on a 6 wheeled vehicle without some attention to this problem, the wheel base can be very long, so it will be much worse in this circumstance.

 

Has anyone fitted the Brassmasters version to D&S kits. I have some NER versions already built and they wont go around curves at all the centre wheel derails even with a large lump of lead underneath !!

 

Mick,

 

They ought to. The element to these that I did not mention was that they also include compensation. At one pivot point, there are two rubbing plates either side of the pivot. At the other pivot, there is a washer, thus creating the three points of compensation. As such, the vehicle load is being distributed across all three of the axles. This will be different to the floating axle, which is reliant on merely the weight you can load on it.

 

However, proof of the pudding is in the eating and I am in the process of fitting the assembled system to an etched brass kit (not D&S but the etched kit is not designed to receive this, so I suspect it will be comparable). I will report back here in a couple of weeks. Certainly, the other six wheeled vehicles that I have and rely on a floating axle are very light footed to say the least..............

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thanks, the D&S kits use a fixed end axle , the center axle just hangs on a piece of wire which is fixed between the two outer axles and two push down slots either side of the hanging axle to prevent movement forwards and backwards, and the other end axle is compensated in that it swings from side to side ( if that makes sense) in a cradle type etch

 

Mick

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Phil,

 

Interesting point about the differences on the chassis types.

 

I get the point about the leading/trailing wheels not being parallel with the rail head except on the true cleminson bogie. However, on any four wheeled vehicle this would be true as well and as the distance from the pivot to the axle on the brassmaster's cleminson (to look after my descriptions!) is quite small, this can not be a big issue? Certainly, on a 6 wheeled vehicle without some attention to this problem, the wheel base can be very long, so it will be much worse in this circumstance.

 

 

 

Mick,

 

They ought to. The element to these that I did not mention was that they also include compensation. At one pivot point, there are two rubbing plates either side of the pivot. At the other pivot, there is a washer, thus creating the three points of compensation. As such, the vehicle load is being distributed across all three of the axles. This will be different to the floating axle, which is reliant on merely the weight you can load on it.

 

However, proof of the pudding is in the eating and I am in the process of fitting the assembled system to an etched brass kit (not D&S but the etched kit is not designed to receive this, so I suspect it will be comparable). I will report back here in a couple of weeks. Certainly, the other six wheeled vehicles that I have and rely on a floating axle are very light footed to say the least..............

 

I agree that the wheels not being parallel with the track is not too much of an issue but the side forces on the centre wheels change quite a lot as the lever ratios change when you alter the relationship of the pivot points

There have been some interesting ways of getting 6 wheelers round bends used by different railway companies. The North British Railway used a fixed centre axle with two pony trucks with heavy side control springs on several different types of goods vehicles, their 15 ton vans were built in batches of 25, the first 3 batches had the pony trucks but the last reverted to a rigid chassis and the LNER converted the rest after the grouping so perhaps it didn't work so well.

Most companies tended to use longer spring hangers on the centre axle to allow some sideplay.

In models the biggest problem seems to be with vehicles rocking on the centre axle over uneven track, worst on curves where it can cause the leading flanges to lift clear of the track and go off in a straight line, it can be overcome by allowing some vertical play and very light springing on the centre axle. This was the reason I allowed the centre axle of the NWNGR Cleminson to float(all be it weighted) and carried the weight of the coach on the outer axles. The guides are actually lengths of 3mm x 3mm brass channel with the flanges inside one another arranged so that they allow equal rise or fall either side of the normal for level track. Even my tracklaying isn't bad enough to push that amount of play to the limit!

 

Phil T.

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It is now many years since I first built a 6 wheeler with the suspension provided in the kit, which had something akin to a Cleminson truck, but without compensation. I tried it round the curves of Bonnybridge and of course it fell straight off. My thoughts then turned to a fixed axle at one end, with the other two axles on a 4 wheel bogie. This gave compensation, but the sideways movement was inadequate for the curves. On the sharper curves it's necessary for the centre wheelset to be right over to one side, while the outer wheelsets are right over on the other side. I knew about Cleminson trucks, but not how to make them compensated. So I did some thinking and came up with the top example which has one end as a fixed axle for compensation, but also moving radially. It works, but because the pivots are midway between the axles the weight distribution is uneven, 50% on the midle axle and 25% on each of the others. My next try was the second example, which was cobbled together from the bits provided in the kit, and works the same way as the first example.

I felt that I had it sussed and was quite pleased with myself, then Brassmasters brought out their Cleminson trucks, which do the same job and are much less of a fiddle to make. The main difference with them is that the centre axle is non rocking, but the outer axles can rock, for compensation. Also the pivot points have been moved nearer the outer axle, giving better weight distribution. The downside to this is that if the centre axle moves 2mm sideways, the outer axles can only move 1mm sideways, imposing limitations on the radius it can cope with.

All the systems have a fair bit of friction and need a fair bit of weight to keep the wheels on the rails. I wouldn't now use anything but the Brassmasters system, for it's ease of construction and functionality. I also think that for the sort of radii we tend to use only the Cleminson type truck will function reliably, especially in P4. However I'm sure somebody will prove me wrong!

 

Allan

post-4979-127559018282_thumb.jpg

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I think the system that Dave at Roxey Mouldings designed was even simpler and achieved great track-holding results.

It doesn't have anything hanging down to spoil the profile from a low viewing angle.

I then took it and, with Daves permission, redrew it to allow for adjustable wheelbases and another one can be sprung.

I can post examples if people would like to see what I am talking about.

Cheers

Ian in Blackpool

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Okay, the lower picture shows all three types. The front one is the Brassmasters, the middle is my version of the Roxey one as compensated and the rear as sprung.

The top picture shows the compensated version. The middle axle slides sideways, guided by slots in the etch and the outer W irons swivel on a butterfly type pivot. As

the central unit moves to one side the wire causes the outer units to swivel. The central and one end can also rock on the compensated version or all three axles are sprung

on the, er, sprung one. Oh yes, the holes allow the w-iron carrying unit to be set at different wheelbases.

post-2173-127594231083.jpg

post-2173-12759425884_thumb.jpg

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It may be the way the brassmasters one works, and as you note it will go round tighter curves with less displacement of the centre axle however the true "Cleminson patent" chassis has the outer trucks pivotted above their axles.

 

The real problem is that over the years any 6 wheel articulated railway vehicle chassis has been described as a "Cleminson " and in reality only one particular patented design is truly the Cleminson patent system, the others should be described simply as articulated or radial chassis.

 

The one under my NWNGR coach in the photo's is the true Cleminson design, I spent a good while researching it before I built it. It was built purely to find out whether it would work scaled down and just to see if I could do it in 7mm/1ft. The answer in both cases was yes, but in model form it needs a fair amount of vertical movement in the centre truck even with well laid track (which mine wasn't!) and it would work better and go round tighter curves using true scale 14mm. gauge rather than my 16.5mm. gauge track.

 

Phil T.

 

I'm rejoining this discussion a bit late as I have been away on holiday. I agree with Phil's comments last week (but then I would anyway as I've known him for 30 years) :D although things have moved on a bit since then with the discussions earlier today about other variations.

 

I posted the first reply to this enquiry back in January and Phil's NWNGR coach follows the original 1878 Cleminson drawing from The Engineer magazine and the Southwold book mentioned earlier and has the correct type of link between the outer trucks and the centre axle - none of the other variations have the same pivot system although I guess that in most cases the end result is the same ;)

 

Mike

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I realise the photos aren't great. Here is a drawing that may show the parts better for the compensated version. You can see the W iron carriers that can be fixed at the various wheelbases.

post-2173-127594348406.jpg

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I realise the photos aren't great. Here is a drawing that may show the parts better for the compensated version. You can see the W iron carriers that can be fixed at the various wheelbases.

A very nice design Ian. Although it has compensation it is obviously designed on the KISS principle.

 

Just a query on the pivots, is the wire soldered into the eyes on the outer trucks, just relying on the flex of the wire for movement, or does it float in them.

 

And a comment, to get "Cleminson" geometry to the movement the eyes on the outer trucks would need to be on an arm extending towards the inner truck to bring them about central between the axles and the wire would definitely need to float in them whilst being soldered to the centre truck eyes. But as a way of getting ordinary 6 wheelers around model curves your design looks excellent.

 

Are you likely to make the RMweb members day at Mickleover in July? I would be interested in having a chat with you about a project I have and seeing your chassis in the flesh(brass?).

 

Phil T.

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Hi Phil

I'm afraid I don't get about much. I manage Scalefourum and North and thats about it nowadays. I have a teenage family that demands me at most weekends!

The wire is soldered to one end unit only, this found after quite a few variations trialed. This seems to alow the twisting of the outer units as the central one slides sideways to work the best.

The wire is just 0.45mm brass from Gibson. Again this has come about after a couple of trials with differing diameters.

I should have said that the central unit also floats a bit and can move up and down about 0.75mm to cater for track dips and bumps.

The sprung version does not have any rock or float as all the axles can move up or down about 0.75mm.

My email is my username as shown athotmaildotcom if you want to have a chat off topic.

Cheers

Ian

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