buffalo Posted January 5, 2013 Share Posted January 5, 2013 I think I may have missed what you were interested in - see the comment recently added on http://PaulBartlett.zenfolio.com/gwropenmerchandiseowv/ee8145e3 I have checked my photos but I didn't take the other end. It had been a long trip and the mineral wagons were far more interesting! It may still exist at the Severn Valley Railway. Paul Bartlett That looks like DCI to me, Paul, same as the Pooley van in your earlier post. So, yes, the comment on your photo is correct. It's difficult to tell with the door in the way, but the angle of the pushrod suggests that it needs a lifting lever to operate. At the lever end, I think I can see a bit of the ratchet and the drop link from the quadrant to the swan neck lever. Industrial's vintagecarriagetrust photo confirms this, look at the pushrod on the far side. Why did they have to take the photo from that side Still no DCII detail photos... Nick Link to post Share on other sites More sharing options...
Castle Posted January 5, 2013 Share Posted January 5, 2013 Hang on Nick - only went to 81E today for the first time this year!* Ok - here we go then, Crocodile No. 41934, I managed to (just) go under and take a picture or two... There we go - I hope this helps! All the best, Castle *Just pulling your leg! Link to post Share on other sites More sharing options...
buffalo Posted January 5, 2013 Share Posted January 5, 2013 Well done, Castle. I didn't mean it to sound like a complaint that you hadn't dropped everything on New Years Eve and gone out to photograph the Crocodile for us. It was really a comment on how we've been able to find good examples of DCI and DCIII, but not DCII. Curiouser and curiouser What I can't see in the first photo is whether or not there are hand levers at each end of the cross-shaft. I assume it's the same as on this photo and others in Russell, etc. They do appear to be fixed to the same shaft because both handles appear to operate together. Also on these long vehicles it appears that the brakes on each bogie are independent. The interesting thing that your photos appear to show is that the ratchet, lever and pawl assembly are on a separate short cross-shaft mounted centrally and some way inboard from the end. This shaft does not extend to either side so is quite separate from the one carrying the handles. Are the second and fourth photos taken looking inwards from the end? If I'm reading this correctly, there should be a link from the handle shaft to this one, probably the one that appears diagonally at the top of the last photo. If so, what I can't see is the rod that actually operates the brakes -- maybe it's hidden from sight and comes from the other side of the ratchet, perhaps linking to the part that hangs down behind and below the ratchet shaft? So what is it? It would say it's a variation on DCII, but it's not the same as DCII on a four-wheeler. It appears to partially confirm my speculation back in #10 about the difference from DCIII. It certainly looks like we've got a bit further but we need to keep looking for four wheel eamples. Either that or spawn a new topic on DC variations on bogie vehicles... Nick Link to post Share on other sites More sharing options...
hmrspaul Posted January 5, 2013 Share Posted January 5, 2013 There are handles at both ends of the shaft, there are numerous bogie wagons with some form of DC brake here http://paulbartlett.zenfolio.com/gwrcrocodile It is conventional for brakes to operate only on one end of bogie wagons, especially those with a well as there is no way to link one end with the other. Paul Bartlett Link to post Share on other sites More sharing options...
Castle Posted January 5, 2013 Share Posted January 5, 2013 Well done, Castle. I didn't mean it to sound like a complaint that you hadn't dropped everything on New Years Eve and gone out to photograph the Crocodile for us. It was really a comment on how we've been able to find good examples of DCI and DCIII, but not DCII. Hi Nick, It wasn't taken as such mate - don't worry! All the pictures were taken from the outer end looking in as you can't get under it from any other way without having eaten far less pies than me... Paul is right in saying that the bogies are braked independently of each other. The well drops down surprisingly close to the rail head and there is no way you would squeeze a linkage in there too. Interestingly, the bits of the well section that hold up the wooden floor panels are made from old broad gauge bridge rail! In picture two you can see the linkage that connects the brake handle cross shaft to the shorter ratchet cross shaft. The next picture below shows a little more of the mechanism dropping down to the bogie The next one shows the spring attached to the ratchet arm. Rotate picture 90 Degrees And finally, the adjustment bit on the end leading to the bogie mechanism. Rotate picture 90 Degrees It is a bit cramped under there and try as I might, my iPad and terrible photography skills combined to the effect seen but it should give you a rough idea of how it all works. I hope this helps! All the best, Castle Link to post Share on other sites More sharing options...
RMweb Gold 57xx Posted January 5, 2013 RMweb Gold Share Posted January 5, 2013 I stumbled on this really useful document last night whilst trying to research DCIII brakes better (I'm trying to use the Bill Bedford DCIII etch but finding it has many failings!) Whilst not pictures of prototypes, there are some handy diagrams of the layout of the various DC options, with one showing DCII on page 34. The diagram of the DCIII underframe on page 34 does have an error on it though with the connection to the brake rod showing in between the secondary end lever hangers, rather than being on the outside. It's correctly described later on though on page 36 with a prototype pic. I've mailed the author to let him know. Morgan Designs GW underframes Link to post Share on other sites More sharing options...
steveb860 Posted January 5, 2013 Share Posted January 5, 2013 Received this handy little etch from MRD today, retails for only £3 (plus P&P). Link to post Share on other sites More sharing options...
RMweb Gold 57xx Posted January 5, 2013 RMweb Gold Share Posted January 5, 2013 Interesting, did the 11ft wheelbase wagons have different hanger arrangement for the brake levers? The width of the lever hangers (on the bottom of the etch) don't look right for either model of brake to me. Just looked on their site to see if there were any pics for the 9ft wheelbase kit and saw they give an incorrect statement about construction of the brakes: "The distinctive toothed quadrant is centrally mounted on the crosshaft (sic)". I guess that is because of the incorrect hanger spacings. Link to post Share on other sites More sharing options...
buffalo Posted January 5, 2013 Share Posted January 5, 2013 I stumbled on this really useful document last night... That's a very useful document, Ric. Thanks for posting it. From a quick reading of the prototype notes and the drawings and photos, It does confirm that there are no known surviving official drawings of DCII and it appears that Brian Morgan and others, including Roger Tourret, have not been able to find surviving examples. Hardly surprising when you consider how short-lived DCII was, apart from a few exceptions, and that most would have been converted to a form of DCIII or lever brakes at some point. I see what you mean about the drawing on p34, it is a little confusing. However, the drawing of DCII on the same page has a more serious error. The rod from the ratchet quadrant to the central cross-shaft is shown linking to the ratchet below the shaft. If it were in the position shown then the rod would be in compression when the brake was applied and would almost certainly bend. It should, of course, be in tension and linked to the ratchet above the shaft as with DCIII. This can also be seen from the positions of the pushrods in Russell's figure 37 of an O13. In fairness, though, it's probably very easy to make these errors when drawing them upside-down. One other point that interested me was that although the ratchet in the sketches on p34 is the same shape for both types, those on p37 are different. The latter shows the familiar 'scythe' shape of DCIII, but the DCII drawing suggests a quadrant with single large cutout. I'm sure I've seen a similar sketch somewhere else, though can't remember where. I wonder where that comes from? Interesting, did the 11ft wheelbase wagons have different hanger arrangement for the brake levers? The width of the lever hangers (on the bottom of the etch) don't look right for either model of brake to me. Just looked on their site to see if there were any pics for the 9ft wheelbase kit and saw they give an incorrect statement about construction of the brakes: "The distinctive toothed quadrant is centrally mounted on the crosshaft (sic)". I guess that is because of the incorrect hanger spacings. I think what's wrong with those hangers at the bottom is that they are both the same length. For DCIII, the one at the ratchet end should be a little more than half the width between the solebars, the other should be a little less than half. I assume you are only meant to use one hanger from each part for DCII. The "centrally mounted" bit is probably just poorly worded. For DCIII the ratchet should usually be central under the frame, not central on the shaft. Nick Link to post Share on other sites More sharing options...
steveb860 Posted January 5, 2013 Share Posted January 5, 2013 "I think what's wrong with those hangers at the bottom is that they are both the same length" However it is very easy to cut through the hanger and mount at correct width Link to post Share on other sites More sharing options...
buffalo Posted January 5, 2013 Share Posted January 5, 2013 Perhaps I should have said "all that's wrong with". As you say, it's not the end of the world, but you do need to know the correct width and I suspect a fair number of users might not. Nick Link to post Share on other sites More sharing options...
RMweb Gold 57xx Posted January 5, 2013 RMweb Gold Share Posted January 5, 2013 However, the drawing of DCII on the same page has a more serious error. The rod from the ratchet quadrant to the central cross-shaft is shown linking to the ratchet below the shaft. If it were in the position shown then the rod would be in compression when the brake was applied and would almost certainly bend. It should, of course, be in tension and linked to the ratchet above the shaft as with DCIII. This can also be seen from the positions of the pushrods in Russell's figure 37 of an O13. In fairness, though, it's probably very easy to make these errors when drawing them upside-down. I don't really know much about the DCII, but what you say makes sense. As you say, it's not easy drawing upside down. In my first few attempts of putting together some semblance of DCIII vac fitted on some Parkside kits, I had double check and correct things working on an upside down chassis from right way up drawings. One other point that interested me was that although the ratchet in the sketches on p34 is the same shape for both types, those on p37 are different. The latter shows the familiar 'scythe' shape of DCIII, but the DCII drawing suggests a quadrant with single large cutout. I'm sure I've seen a similar sketch somewhere else, though can't remember where. I wonder where that comes from? I reckon the sketchs on p34 are just supposed to be representative, not a detail of the ratchet. I would wager the actual ratchets in the relevant etches are correct as per p37. I think what's wrong with those hangers at the bottom is that they are both the same length. For DCIII, the one at the ratchet end should be a little more than half the width between the solebars, the other should be a little less than half. I assume you are only meant to use one hanger from each part for DCII. The "centrally mounted" bit is probably just poorly worded. For DCIII the ratchet should usually be central under the frame, not central on the shaft. Yes, that's exactly what I was thinking, they shouldn't be the same width. I have a copy of a works drawing of the DCIII brakes that someone posted in a previous thread that shows the ratchet is offset from the centreline of the wagon, towards the side with the shorter of the brake lever shafts (the secondary shaft as Morgan describes it). With this in mind, neither interpretation is correct. Link to post Share on other sites More sharing options...
RMweb Gold 57xx Posted January 5, 2013 RMweb Gold Share Posted January 5, 2013 "I think what's wrong with those hangers at the bottom is that they are both the same length" However it is very easy to cut through the hanger and mount at correct width That is true, but you shouldn't have to if the etch was designed properly. Most of the MRD parts purport to fix errors in kits (eg their roof etches and replacement ends for wagons), so you kind of hope they'd get the details right on the brake etches. I'm glad someone is taking the time to produce these, it's just a shame they are not accurate for those that want such things. Link to post Share on other sites More sharing options...
buffalo Posted January 5, 2013 Share Posted January 5, 2013 ...I reckon the sketchs on p34 are just supposed to be representative, not a detail of the ratchet. I would wager the actual ratchets in the relevant etches are correct as per p37... Agreed, I just wish I knew where that shape came from... Yes, that's exactly what I was thinking, they shouldn't be the same width. I have a copy of a works drawing of the DCIII brakes that someone posted in a previous thread that shows the ratchet is offset from the centreline of the wagon, towards the side with the shorter of the brake lever shafts (the secondary shaft as Morgan describes it). With this in mind, neither interpretation is correct. Ah but there's drawings and then there's reality If you look back at my photo of Didcot's P17 in post #10, you'll see the ratchet is almost exactly on the centre line of the wagon. That is one of a set of photos showing the brakegear over the full length of the wagon. At the other end, with the shorter shaft, the rod and link are a good six inches off-centre, as you would expect because the shaft is shorter at this end. In between, the rod linking to the secondary shaft is at a slight angle to the centre line and the hanging link near the centre is offset so that the rod clears the vertical arm from the central cross shaft. I've seen other examples where the ratchet is indeed off-centre just as on the drawings. In practice I think there was a certain amount of variation. Nick Link to post Share on other sites More sharing options...
RMweb Gold 57xx Posted January 6, 2013 RMweb Gold Share Posted January 6, 2013 I think the P17 is one of many exceptions/variations from what could be considered "normal" though. I'm building a Cambrian kits of the P15 so have been looking at lots of pics recently and one other thing I noticed about the ballast wagons is the brake lever hangers are a different shape, more of a proper V shape rather than having one leg vertical as here. If you look at Miss Prism's pics here (1st pic) and JackBlack's pics here (3rd and 7th pics down), it clearly shows the ratchets roughly in line with an end stanchion. I believe this to be the more common configuration. I'm sure the more diagrams we look at, the more variations would become apparent e.g. different shaped lever hangers, offset V hangers, rods using different alignment, with/without Hayward adjusters etc etc. Link to post Share on other sites More sharing options...
buffalo Posted January 6, 2013 Share Posted January 6, 2013 Though remarkably consistent in form it is as well to remember that DCIII brakes were produced over a long period from 1906 to 1939. It is therefore hardly surprising that there were some variations. From photos in Russell's books and Atkins et al. the V-shaped hangers appear to be a mid-thirties form and limited to P15 and P17, presumably also P16 though I haven't noticed one of those. Earlier P diagrams have the more 'normal' form in which the short arm is vertical. Other patterns exist, for example one in which the short arm is angled in the same direction as the long one. Another hanger pattern has the long arm curving upwards to meet the solebar. As to the handle shaft lengths, yes, the roughly two-thirds and one third widths are probably the most common, but there is a wide variation. I suspect the variation relates to the arrangement of underframes which vary through time and between diagrams as this provides constraints on where the various links and hangers may be placed. Rather than debating what is common, I think it is clearly a case, as always, of examining dated photos of the wagon type of interest. Nick edit: ps I don't have a copy of Russell's wagon plans book, can anyone say whether this is likely to provide further enlightenment? Link to post Share on other sites More sharing options...
Kenton Posted January 6, 2013 Share Posted January 6, 2013 Perhaps I should have said "all that's wrong with". As you say, it's not the end of the world, but you do need to know the correct width and I suspect a fair number of users might not. Spot On. Just emphasising the "incorrectness" of any supplied "kit". Something that claims to be what it is not, requiring folk on RMWeb to correct, and any user to be a member and spot it. I hope they are quickly amending instructions to correct this quite serious fault. It is not what it claims to be, otherwise. The confusion over DCI, DCII, DCIII is bad enough without it being perpetuated by a supplier convincing us of something that isn't. Link to post Share on other sites More sharing options...
buffalo Posted January 6, 2013 Share Posted January 6, 2013 The P15 has an over all length of 16'6" against the normal 16'0" and this is the reason for the odd shape lever hanger...An interesting theory, and you might add that P17 was 21'6" whilst the earlier P12 was 21'0". But why would that be done? The only reason I can think of would be so that the same pull rods could be used as on the shorter wagons. Somehow I doubt that. The rods are hardly major components and would take only a few minutes to fabricate. You could, of course, argue for standardisation and carrying stocks of spares. However, looking at photos it does not look like the V-shaped hangers each bring the handle rod three inches closer to the centre. Measuring from the 4mm drawings in Atkins et al. is not going to be exceptionally accurate but it's worth noting that the distance between the handle shafts on P15 appears to be about 3" longer than that of O15, a 16'0" wagon with DCIII and 'conventional' hangers....This photo shows the ratchet that is shown as on the O13 the china clay wagons...You've lost me here, that's DCIII. Where is this shown for O13?...This photo is the shape ratchet (in this case on the end of a swan neck leaver)that is shown on the O6 and O10 wagons in the Russell drawing Nice photo, but that's DCI. I don't think anyone has questioned what that looked like as we have official drawings and a fair number of photos. Looking at a photo in the Russell book at a photo of a O13 but showing the door end, the leaver on the cross rod between the brake blocks looks to be off set very much like on the DC3 brakes ie the long rod end... Yes, that's really where we started. The ratchet is also, of course, over towards that side and we can only just see a small part of it. Nick Link to post Share on other sites More sharing options...
buffalo Posted January 6, 2013 Share Posted January 6, 2013 Nick Reading these posts of yours I am confused what you are trying to get at, as one case you are on about the shapes of the ratchet that were used on the DC2 brakes and using what is shown in the official drawings and I have posted photos of the two types of the ones that were used on the DC2 brakes (O13 was built as DC2) and then you complain over this. Perhaps you've missed a couple of crucial points in the depths of the topic. We began with the question about what the DCII ratchet looks like and have been through various meanderings around that but have not yet found a suitable photo. In post #32, Ric (57xx) drew attention to Brian Morgan's instructions for his underframe kits. On p37 of this document are drawings that show three different ratchet forms, one for each of the main DC types. The drawing of the DCII type is quite different from the later DCIII type that we are all familiar with. So the question might now be rephrased as 'What is the evidence for that shape?' or, alternatively, 'Did all DCII brakes have ratchets of that shape?' One possiblity, though I have no evidence for this, is that early examples of DCII used a ratchet shaped like that in Brian Morgan's document, but that later ones used exactly the same ratchet as was used on DCIII. Remember that O13 is a late oddity that was produced some six years after the the introduction of DCIII. The usual explanation for this was that it kept the brake mechanism and handles from being clogged up with clay by having them placed at the end away from the door. Your first photo in #43 shows a DCIII system, not DCII. The lever that rotates the ratchet when the brake is applied and releases the pawl when the brake is released has the pull rod from the opposite end linked to it below the shaft. DCII only has the one rod linked to the ratchet. Your second photo is a DCI ratchet which we know is quite different. Neither are evidence for these question about DCII. If I understand you correctly, you are saying that your first photo is of an O13. That surprises me as Atkins et al. suggest that all were converted to Morton brakes after 1939. Have the DCIII brakes been fitted in preservation or was it an in-service conversion? If the latter it may well be that the original ratchet was reused. Do we have any evidence? It would be helpful if you could identify these wagons. Nick Link to post Share on other sites More sharing options...
richbrummitt Posted January 6, 2013 Share Posted January 6, 2013 edit: ps I don't have a copy of Russell's wagon plans book, can anyone say whether this is likely to provide further enlightenment? Most of the diagrams in the plan book don't have complete underframe detail. Many of them have the brake linkages indicated by single lines, if at all and the detail is not as clear as it might be because the majority are reproduced at 4mm:1ft. Link to post Share on other sites More sharing options...
buffalo Posted January 6, 2013 Share Posted January 6, 2013 Thanks, Rich. Presumably the diagrams are much the same as those it Atkins et al. and at the end of Russell's first wagon book? Nick Link to post Share on other sites More sharing options...
richbrummitt Posted January 6, 2013 Share Posted January 6, 2013 Pretty much. They are undoubtably better than the loco weight diagrams as a modelling aid but probably have some similar caveats. Link to post Share on other sites More sharing options...
hmrspaul Posted January 7, 2013 Share Posted January 7, 2013 Pretty much. They are undoubtably better than the loco weight diagrams as a modelling aid but probably have some similar caveats. Correct. All of these books are reproducing the GWR weight diagrams. Unlike any other railway I've come across the GWR appears to have largely used a reduced GA so they show the brake rigging, running gear etc. But they are reproduced very small - much smaller than any of the other companies diagrams. If you let me know which one you want I'll scan an original for you. Paul Bartlett Link to post Share on other sites More sharing options...
buffalo Posted January 8, 2013 Share Posted January 8, 2013 Looking more closely at some of these diagrams in Atkins et al., it's clear that many of them do show a good representation of the ratchet shape for DCIII brakes as well as for the few examples of DCI. For example, O4 and O15 on p150 of the 1986 combined edition. There are a few where where the shape is crudely drawn and there are some where no brakegear is shown, but most are quite recognisable. With this in mind I looked for DCII examples and found two, perhaps three, different ratchet shapes: O2/10 opens (1905-7) on p154 shows a quadrant with two cutouts very similar in form to the typical DCI ratchet. R1 manure wagon (1905) on p166 shows a quadrant with a single large cutout. W5 MEX B (1902-11) on p186 shows another single cutout but with what looks like the beginnings of the 'scythe' shape of the typical DCIII ratchet. The latter two look like Brian Morgan's sketch. I wonder whether this can be taken to support my earlier suggestion in #48 that there was an evolution in the ratchet shapes fitted to DC brakes? Does the O13 diagram show a scythe-shaped ratchet on DCII brakes? ... If you let me know which one you want I'll scan an original for you. Paul, that's a kind offer. If you can find the time to scan them I think it might be instructive to compare O2, W5 and O13. Nick Link to post Share on other sites More sharing options...
buffalo Posted January 8, 2013 Share Posted January 8, 2013 Sorry, industrial you were just not very clear about it. You posted photos of DCI and DCIII brake and appeared to be claiming that they were DCII. You also appear to claim that there were only the DCI quadrant pattern and the DCIII scythe type. Read my last post, the diagrams show several different types on DCII. Nick Nick Reading these posts of yours I am confused what you are trying to get at, as one case you are on about the shapes of the ratchet that were used on the DC2 brakes and using what is shown in the official drawings and I have posted photos of the two types of the ones that were used on the DC2 brakes (O13 was built as DC2) and then you complain over this. Link to post Share on other sites More sharing options...
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