pete_mcfarlane Posted February 15, 2014 Author Share Posted February 15, 2014 Colin, That's quite interesting - so adding the strengthening partitions (to stop distortion) actually causes some of the distortion in the first place. Some food for thought there. Link to post Share on other sites More sharing options...
MikeTrice Posted February 15, 2014 Share Posted February 15, 2014 Correct. The alternative is to use cyno to fix them. Link to post Share on other sites More sharing options...
Colin parks Posted February 16, 2014 Share Posted February 16, 2014 Hi Pete me again. Perhaps I should have been clearer on partitions and their fixing from my limited experience: They are just clipped in on my EMUs these days, with small locating lugs on the insides of the sides to locate them, so no glue is used at all. On the first of my models, the partitions were tacked into place with a glue like UHU. If you look at David Jenkinson's methods of coach building, it is clear that he built the coach sides and ends around a rectilinear box which contained all the interior detail, so the partitions in his coaches never came into contact with the actual sides. Certainly, strengthening of the sides is a good idea. By adding layers or strips along the inside of the side to get a thickness of 40 thou., it will become quite rigid. Adding extra strips at cant rail level to achieve a thickness of 60 thou. will also help get rid of the wavy top edge problem. If the sides bow out slightly (as they tend to, having only had solvent applied on the inner face), they will be brought back into line once fixed to the roof. All the best, Colin Link to post Share on other sites More sharing options...
dasatcopthorne Posted February 16, 2014 Share Posted February 16, 2014 A rummage through the boxes of bits has turned up most of the parts I need to finish this coach. First of all were a couple of sets of MJT compensated bogies, one of which has been soldered together tonight. The wheels are from the same people as Black Beetle motor bogies, and also were found in one of my boxes. 000_0022.JPG I also found some DC Kits BR2 single bolster bogie sideframes - I'm still undecided about whether to use these as they're a bit crude. I did use them on my DC Kits 2-EPB, but comparing them with photos of the real things shows how much work is needed to bring them up to spec. They're also 1mm too long in the wheelbase, and I don't have enough to do the driving trailer as well. Some more thought is needed - it's a shame Bachmannn don't sell their ones as spares. 000_0023.JPG I've also made a start on the motor coach drawings. This is the current state of progress. motor.jpg I've got two drawings to base this on - the BR weight diagram showing the 'corridor' side, and the one in the Cheona book of DMU drawings. I started by tracing the latter in Inkscape, as I did with the trailer, but ended up moving almost every element of the motor end around until it looked right. I'm increasingly thinking that the drawing was based on photos and a few known dimensions. And not very good photos either - for example the short frame motor coach had two part handrails to the driver and guard doors, the drawing shows one part handrails as per the long frame units. The group of four grills on the motor coach has rounded bottoms to the lower grills when the real thing doesn't and so on. I got this far last night, and the next step is to draw it our (using a pen in the Silhouette) to check that it looks OK. Talking of photos, I've only got a few of my own photos of the preserved Hastings, so I've been making use of lots of photos off www.preservedthumpers.co.uk. Well worth a visit. This is one of my handful of photos of a real Hastings, taken when it visited Nottingham in 2009. I've also got a few of the motor coach roof that should come in handy later on. 100_0311.jpg Hi Pete. Will this help. It's 1202 on 01/01/75. Got the other rooves when you need them. I also have a few measurements from a 6S D/M Dave Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 16, 2014 Author Share Posted February 16, 2014 Dave, That's extremely useful and answers a couple of questions! For starters I was wondering what type of ventilators these units had - the answer in this case is several. It also looks as though the driving trailer still has the same equipment boxes on the end as it had in its EMU days. It's be interested in any more information you've got, especially the measurements of the motor coach - this is the current state of the motor coach drawings and there's a fair amount of guesswork in there. 3 Link to post Share on other sites More sharing options...
dasatcopthorne Posted February 16, 2014 Share Posted February 16, 2014 Dave, That's extremely useful and answers a couple of questions! For starters I was wondering what type of ventilators these units had - the answer in this case is several. It also looks as though the driving trailer still has the same equipment boxes on the end as it had in its EMU days. It's be interested in any more information you've got, especially the measurements of the motor coach - this is the current state of the motor coach drawings and there's a fair amount of guesswork in there. motor2.jpg Got to go out for Anniversary dinner this evening but will post more later. Should be useful. Dave Link to post Share on other sites More sharing options...
dasatcopthorne Posted February 16, 2014 Share Posted February 16, 2014 Dave, That's extremely useful and answers a couple of questions! For starters I was wondering what type of ventilators these units had - the answer in this case is several. It also looks as though the driving trailer still has the same equipment boxes on the end as it had in its EMU days. It's be interested in any more information you've got, especially the measurements of the motor coach - this is the current state of the motor coach drawings and there's a fair amount of guesswork in there. motor2.jpg Pete. Firstly, everyone seems to get that driver's off-side door wrong. It's only 21" wide. Like other DEMUs Hope these help Dave Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 17, 2014 Author Share Posted February 17, 2014 Thanks, those are extremely useful. My next step is going to be comparing your dimensions against my Inkscape drawing and seeing how good my guesswork is. My drivers offside door is wrong for starters...... Link to post Share on other sites More sharing options...
dasatcopthorne Posted February 20, 2014 Share Posted February 20, 2014 Steve. Took these yesterday. They are of 1123. Lots of details are the same as on 6L/6S/6B. Sorry about the shite mobile phone quality. Can get them properly again if you want. Hope they help later. Dave 1 Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 20, 2014 Author Share Posted February 20, 2014 Thanks - they're still useful, despite the phone quality. Especially the shots of the underframe gear. So far I've been tweaking the trailer coach to match the photos. I'd got the door stops in the wrong place, so these were removed and new ones fitted (and the Inkscape drawings updated). The biggest surprise was the missing corridor connection at the end towards the driving trailer. I'd assumed that these had been left in situ, but it looks as though the connector was mostly removed, but the fixed parts left in situ so that it could be reinstated. So the Comet casting I fitted has been carefully removed, and I'll need to do some scratchbuilding. Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 25, 2014 Author Share Posted February 25, 2014 I've tweaked the drawings to match Dave's dimensions. Mine were a long way out, and the less said about the ones in the Cheona book the better. This is now ready for cutting on Wednesday night. I'm now on my third go at the roof for the trailer second, the first couple of goes having succumbed to distortion. This time I took no chances - the base is 3 layers of 40 thou laminated together and clamped against my bending bars whist they set. The roof formers were then added, along with some cross pieces to stop the roof going banana shaped and holes to let any solvent fumes out. . It's now have 2 layers of 10 thou plasticard wrapped over it (with solvent applied only at the edges), and now will be put aside for a week or so to check for any distortion Then I'll cut it to shape and detail it. 2 Link to post Share on other sites More sharing options...
dasatcopthorne Posted February 26, 2014 Share Posted February 26, 2014 I've tweaked the drawings to match Dave's dimensions. Mine were a long way out, and the less said about the ones in the Cheona book the better.app=core&module=attach§ion=attach&attach_rel_module=post&attach_id=388282]100_7166.JPG[/url] No pressure on me then!!! :-))) Best of luck Pete. Dave Link to post Share on other sites More sharing options...
jwealleans Posted February 26, 2014 Share Posted February 26, 2014 Hey Pete, Haven't read back through the whoel thread, but have you tried this Limonene stuff? Geoff Kent reckoned it set more slowly and didn't distort plastikard and Mike T is trying it with apparently good results. Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 26, 2014 Author Share Posted February 26, 2014 I have tried Limonene for some of the joins after reading about it in the MRJ. Experience so far backs what others say - it's less agressive than MekPak but takes longer to set. I did find that the long setting time was an issue on parts of the first layer of 10 thou on the roof. The plastic was soft for a couple of days and so the unsupported bits sagged a little. The second layer as fixed with MekPak and had no such issues. So it looks like a case of different tools for different jobs. Link to post Share on other sites More sharing options...
MikeTrice Posted February 26, 2014 Share Posted February 26, 2014 The plastic was soft for a couple of days and so the unsupported bits sagged a little. It sounds as if you are using it to laminate the two pieces together to hold a shape. I have not done that with any solvent. Geoff Kent's approach is to just glue at the roof edges. Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 26, 2014 Author Share Posted February 26, 2014 That's pretty much what I did - apply the solvent at the roof edge, and the area immediately above it went soft and sagged. It's possible that I'd applied too much solvent to the area, and that's the cause of the problems. Link to post Share on other sites More sharing options...
Colin parks Posted February 27, 2014 Share Posted February 27, 2014 Hi Pete, Just reading the latest posts. I can now see that the Geoff Kent approach is similar to that of building an aircraft wing with the sheet material not really laminated at all. If I were to do this for a coach roof I would use Liquid Poly and apply it with an 00 synthetic bristle brush. Having said that, a coach roof made from 40 thou. sheet clamped in a heated wooden former will never let you down, but I appreciate not everyone will want to do that. It is quite surprising how far even a small amount of solvent will spread, so if the Geoff Kent method is to be successful, it seems to be a case of limiting the spread of solvent inwards from the edges, hence the use of small brush and small amounts of your chosen solvent. The roof does look to be a good one, so fingers crossed! All the best, Colin Link to post Share on other sites More sharing options...
MikeTrice Posted February 27, 2014 Share Posted February 27, 2014 That's pretty much what I did - apply the solvent at the roof edge, and the area immediately above it went soft and sagged. It's possible that I'd applied too much solvent to the area, and that's the cause of the problems. Any chance of a photo? Link to post Share on other sites More sharing options...
pete_mcfarlane Posted February 27, 2014 Author Share Posted February 27, 2014 Afraid no - the second layer (attached with MekPak) has covered the distorted bit. So far this is sag free (although I did feel the need to check *again* before posting that.....) 1 Link to post Share on other sites More sharing options...
pete_mcfarlane Posted March 9, 2014 Author Share Posted March 9, 2014 After a week and a bit the roof showed no signs of distortion, so it has been cut to shape, and detailed. The lighting conduits use guitar string wire and Southern Pride turnings, and the rood vents are MJT. I copied the seemingly random mix of dome and shell vents from the photos. The trailer secondis now doone, apart from the bogie side frames. These are slowly taking shape, using (I think) Replica BR1 bogie kits. The bolster detail was removed and various detail added from scrap plastic. There's still a bit to do. The motor coach and driving trailer are now at this stage. The motor coach is on it's Black Beetle bogies. Since I'm using MJT sideframes these are 34mm wheelbase rather than the correct 35mm, but I have managed to get the powered bogie at the correct (inner) end. The driving trailer is not quite so far advanced. The sides were curved by rubbing them with a knife handle and then laminating the various layers together. After a week or so any distortions were removed by dunking them in a sink full of hot water. I'm still experimenting with these coaches to avoid warping. The motor coach has it's cross partitions glued to the floor, but not to the sides, and the driving trailer has them glued in place using superglue. I'll report back in a week or so on whether they've warped. 4 Link to post Share on other sites More sharing options...
Colin parks Posted March 10, 2014 Share Posted March 10, 2014 Hi Pete, The coaches are looking mighty fine indeed. That roof you have made has a very consistent appearance, so we must take our hats off to Mr Kent (and you!). Are the roofs to be detachable or are you going to fix them in permanently once the coaches are finished? All the best, Colin Link to post Share on other sites More sharing options...
pete_mcfarlane Posted March 10, 2014 Author Share Posted March 10, 2014 Colin, I'm not brave enough to try Geoff Kent's approach of glueing the roof firmly in place. So I'm going to do what I've done with some of my kit built coaches, and glue it in place with PVA or Copydex, so it will come off if I ever need to replace a window or stick a passnger back in place. 2 Link to post Share on other sites More sharing options...
MikeTrice Posted March 10, 2014 Share Posted March 10, 2014 That is looking really nice. Link to post Share on other sites More sharing options...
pete_mcfarlane Posted March 16, 2014 Author Share Posted March 16, 2014 (edited) The Motor coach front end has been detailed, and it now looks a lot more like the real thing. The etched parts are from NNK, and the cast ones from MJT. The gap in the buffer beam is for a Kadee coupled mounted where the real thing had its buckeye. I'm now waiting on some EMU motor bogies from MJT. The underframe gear will be a mix of scratchbuilt, a set of Hornby 73 fuel tanks and some odds and ends from Southern pride. The roof is also under construction, using the same method as the trailer second, with formers on a very soldi (3 layers of 400 thou) base. It's clamped to a set of bending bars whilst it sets to ensure that it's a straight as possible. Lastly, a bit more work has been done on the ex-EPB driving trailer, again using MJT parts. Edited March 16, 2014 by pete_mcfarlane 5 Link to post Share on other sites More sharing options...
Colin parks Posted March 17, 2014 Share Posted March 17, 2014 Hi Pete, Great work there on the unit! Having looked at the prototype photos, I can see why this unit is so worthwhile to model: one straight-sided coach and two with tumblehomes! I think you are onto something with the idea of super-gluing the internal partitions to the sides instead of using solvent - nice one! All the best, Colin Link to post Share on other sites More sharing options...
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