RMweb Premium MJI Posted October 15, 2012 RMweb Premium Share Posted October 15, 2012 I hope it will be an interesting build. It struck me that I have never made any roofs in our present electric oven. All the previous sctrachbuilt units had roofs 'baked' and formed in the solid-fuel Rayburn at our old house. I'm sure it can be done though in a modern oven. (He says, stroking lucky rabbit's foot.) Colin Not so lucky for the rabbit!!!! Anyway I like the superglue idea, I have been building cut & shut coaches and even solvent welded joins are not that strong. Link to post Share on other sites More sharing options...
meld Posted October 15, 2012 Share Posted October 15, 2012 Oh Bloody Hell!! I go away for a couple of weeks and not only do you finish the CIG, But you start another Plastikard Project of Magic ... ( salivates anyway ). Mike Link to post Share on other sites More sharing options...
RMweb Premium Clive Mortimore Posted October 15, 2012 RMweb Premium Share Posted October 15, 2012 Thanks for the picture SRman, The Ajay kit looks like it has the right proportions and would make a good starting point for a Tin HAL. Unlike 4 CIG models available on the market, the AjayTin HAL seems to be accurate re. windows, profile etc.. No crticism of Messrs. Ajay, it's just that I like making things out of plastic sheet! All the best, Colin Hi Colin You are not alone in wanting to make things out of plastic sheet. I just wish my stuff was as good as yours. I look forward to the results of your experiment with super glue for laminating the coach sides. If successful then I might copy the technique for making Gloucester and Wickhams DMUs. Clive Link to post Share on other sites More sharing options...
Colin parks Posted October 15, 2012 Author Share Posted October 15, 2012 Well, 24 hours is enough time spent talking about modelling, so out came the tools for a spot of test-bed work. The sample side is cut from 10 thou. plastic sheet with vertical strips of pre-curved 20 thou. sheet attached behind with solvent - no melted bits yet! The side has lateral strips of 10 thou. sheet top and bottom to bring the side out to a total of 40 thou.. This is roughly scale thickness and also matches the roof section, made from 40 thou. sheet. If the joint between roof and side does not sand up smoothly and become invisible, I shall try plan B. With the side extending right up to the gutter. I did try attaching a strip of 10 thou. sheet to the other side of this roof and curving it down. There is a lot of resistance - even with so thin a material, which could make it hard the anchor down a whole full-length side without melting the surface. This shot is to show the criss-cross lamination going on behind the outer skin. There is also a horizontal strip to strengthen the joint between side and roof. The area around each window has a 1mm rebate to take a simple rectangle of glazing material. The drop light and top light on the door are backed with a rectangle of 10 thou. sheet set in the glazing recess to give the surface texture of near-flush fixed window panes and set-back door glazing. This might sound a little complicated, but it is far easier than cutting individual pieces of glazing and getting them to fit exactly into the window openings. Sanding of the test piece (and possibly cheering or cursing) tomorrow! Colin Link to post Share on other sites More sharing options...
robertcwp Posted October 15, 2012 Share Posted October 15, 2012 When looking at photos, don't forget that 2700 was not like the other 'tin' HALs as it had a 4-Sub motor brake. Its trailer was also built several years after 2693-99. Link to post Share on other sites More sharing options...
Colin parks Posted October 15, 2012 Author Share Posted October 15, 2012 Hi Colin You are not alone in wanting to make things out of plastic sheet. I just wish my stuff was as good as yours. I look forward to the results of your experiment with super glue for laminating the coach sides. If successful then I might copy the technique for making Gloucester and Wickhams DMUs. Clive Hi Clive, I didn't start with the superglue method. I do wonder if it wouldn't be a little risky as once the parts are glued, that's it! From my fiddlings tonight, it looks as if an element of adjustment is desirable. Given that there are no large areas of sheet to laminate, except around the luggage compartment, I might get away with solvent for the construction. I can tell you it is far easier to cut windows in 10 thou. sheet than 20 thou.. All the best, Colin Link to post Share on other sites More sharing options...
Colin parks Posted October 15, 2012 Author Share Posted October 15, 2012 Not so lucky for the rabbit!!!! Anyway I like the superglue idea, I have been building cut & shut coaches and even solvent welded joins are not that strong. Oh, this superglue thing! Hi MJI, It might be that a combination of both solvent and superglue will be needed. I have got on reasonably well with just solvent tonight. What I did use superglue for, on the 4 CIG bodywork, was as a fine surface filler. It is very easy to apply and can be sanded/filed down after an hour or so - if you want to push it a bit. I wonder about how well superglue would be for laminating sheet material as it requires moisture in the air to set. I tink it was developed as a battlefield emergency dressing to close wounds, so needs to react with water vapour/hunidity to set. What would the glue do if trapped in an anaerobic position between plastic sheets? Search me. Pehaps it would never set! Colin Oh Bloody Hell!! I go away for a couple of weeks and not only do you finish the CIG, But you start another Plastikard Project of Magic ... ( salivates anyway ). Mike Hi Meld, Sorry! Coiln Link to post Share on other sites More sharing options...
Colin parks Posted October 15, 2012 Author Share Posted October 15, 2012 When looking at photos, don't forget that 2700 was not like the other 'tin' HALs as it had a 4-Sub motor brake. Its trailer was also built several years after 2693-99. Thanks for the word of caution Robert. I did know there were differences between unit 2700 and the other 'Tin' HALs and that the trailer had a gutter at cantrail level too. It only lasted as a unit until 1968, so wasn't really suitable as a modelling subject. It was just that yesterday I was desperate for anything which gave a clue as to the appearance of a Tin HAL type trailer coach, the picture of 2700 was all I had to go on. Colin Link to post Share on other sites More sharing options...
RMweb Premium MJI Posted October 15, 2012 RMweb Premium Share Posted October 15, 2012 I am doing some of my DMU rebuilds with slow setting Alradite, notably DMS conversions, slow setting is very strong, but I think it would not be much use for laminating. Superglue I use for some jobs, but it sets too fast or not fast enough and sticks things to me. I follow these with interest as plasticard construction fascinates me. Link to post Share on other sites More sharing options...
RMweb Premium zarniwhoop Posted October 15, 2012 RMweb Premium Share Posted October 15, 2012 Apart from the other books mentioned, there is a picture of 2694 in 1971 (blue, FYE) on page 19 of Slam Doors on the Southern. ĸen Link to post Share on other sites More sharing options...
SRman Posted October 16, 2012 Share Posted October 16, 2012 I'll have to check but if the Michael Welch book is the one I think it is, there is an additional pic of a 'tin' HAL under construction. However, it is erroneously labelled as a 4SUB but if you look at the size of the van area ... Edit: no it's not the one I thought it was, see my later post. Link to post Share on other sites More sharing options...
jwealleans Posted October 16, 2012 Share Posted October 16, 2012 What would the glue do if trapped in an anaerobic position ... Pehaps it would never set! Isn't that, in very broad terms, what keeping it in a bottle with the lid on amounts to? I suspect you might be right. Mind you, you'd always be able to adjust it! Another looking forward to following this build - there just aren't enough scratchbuilders these days. Link to post Share on other sites More sharing options...
RMweb Gold Enterprisingwestern Posted October 16, 2012 RMweb Gold Share Posted October 16, 2012 Isn't that, in very broad terms, what keeping it in a bottle with the lid on amounts to? I suspect you might be right. Mind you, you'd always be able to adjust it! Another looking forward to following this build - there just aren't enough scratchbuilders these days. If you glue 2 large ish sheets together air will always get in around the edges, and also, plastic sheet, from a chemical point of view, is not solid, and will still allow air to pass through it. Mike. Link to post Share on other sites More sharing options...
SRman Posted October 16, 2012 Share Posted October 16, 2012 Photos of 'tin' 2HAL units: In Southern Electrics: a Pictorial Survey by Brian Rayner (1975, published by D Bradford Barton Ltd) there are a few pics that may be of interest: page 33 has 2BIL 2133 with a front on shot of the 'tin' HAL style driving trailer. page 34 has a good clear shot of 'tin' HAL s2699 plus a smaller shot of 2698's driving motor from the other side. British Railway Pictorial: First Generation Southern EMUs (Keith Robertson, 2005, Ian Allan Publishing) has two clear photos on page 21 of s2699, one of the driving motor and one of the drivng trailer. This book also has the mis-captioned photo I referred to in my earlier post, in the centre of page 38. In spite of being in the 'Steel bodied suburban' section with the 4SUBs, it is clearly a 2HAL. With apologies if any of these were referred to earlier. Link to post Share on other sites More sharing options...
hayfield Posted October 16, 2012 Share Posted October 16, 2012 If the joint between roof and side does not sand up smoothly and become invisible, I shall try plan B. With the side extending right up to the gutter. I did try attaching a strip of 10 thou. sheet to the other side of this roof and curving it down. There is a lot of resistance - even with so thin a material, which could make it hard the anchor down a whole full-length side without melting the surface. Sanding of the test piece (and possibly cheering or cursing) tomorrow! Colin Colin Great ftuff again, with regard to the gap in the joint. I have found Green Squadron very good for gap filling, I find I have to dilute it slightly with Humbrol Liquid Poly, then leave it at least 24 hours to dry before sanding. Works for me. Other plastic fillers may work just as good, but the thinning down with solvent seems to give it extra adheasion to the surface John Link to post Share on other sites More sharing options...
Colin parks Posted October 16, 2012 Author Share Posted October 16, 2012 Apart from the other books mentioned, there is a picture of 2694 in 1971 (blue, FYE) on page 19 of Slam Doors on the Southern. ĸen Thanks Ken, I'll try and find a copy of that book. Colin Link to post Share on other sites More sharing options...
Colin parks Posted October 16, 2012 Author Share Posted October 16, 2012 If you glue 2 large ish sheets together air will always get in around the edges, and also, plastic sheet, from a chemical point of view, is not solid, and will still allow air to pass through it. Mike. Thanks for the clarification re. plastic and its properties Mike. I have been having a good think about superglue and think its best use on this model will be to reinforce joints and fill hairline gaps on butt joints (as I did when extending the 4 CIG roof ends). Superglueing joints (some 10" long on the roof) and getting everything in perfect position first time sounds scary. I am a great fan of superglue, but for me this is one application I don't think will work. Colin Link to post Share on other sites More sharing options...
Colin parks Posted October 16, 2012 Author Share Posted October 16, 2012 Colin Great ftuff again, with regard to the gap in the joint. I have found Green Squadron very good for gap filling, I find I have to dilute it slightly with Humbrol Liquid Poly, then leave it at least 24 hours to dry before sanding. Works for me. Other plastic fillers may work just as good, but the thinning down with solvent seems to give it extra adheasion to the surface John Thanks John, I will have to find a source for filler. I like the idea of one that can be softened as you describe. Colin Link to post Share on other sites More sharing options...
Colin parks Posted October 16, 2012 Author Share Posted October 16, 2012 The morning after the night before: There is no perceptible join between side and roof after sanding. The greyish shadow in the joint is sanded-down superglue, which has been used to fill some tiny gaps. I think if this was the real carcass, I would run a fillet of superglue down the inside of the joint as an insurance policy. the gap at the top of the door has diminished with the sanding process, so the bevel would need to be greater next time. These gaps are very apparent on the prototype. On this example, no gutter has been added. I think this is the method that I will follow. I occurred to me this morning that if a lamination of 10 thou. plastic sheet came up to the gutters, the area between the gutters would have to be laminated with the same thicknes or it would look a bit odd. More chopping tonight. Now, I really must go and do some work! Colin Link to post Share on other sites More sharing options...
RMweb Gold Re6/6 Posted October 16, 2012 RMweb Gold Share Posted October 16, 2012 Excellent work there Colin. I had a great affinity to these units. I used to travel back home from school every day from Waterloo and always looked out for these on the odd occasion that they were diagrammed, as they were more comfortable to ride in compared to the BILs and old Hals! I look forward to seeing the work as I need to build the BIL/HAL combination. Link to post Share on other sites More sharing options...
RMweb Gold A Murphy Posted October 16, 2012 RMweb Gold Share Posted October 16, 2012 Colin, Be very very careful about using any form of superglue anywhere near your transparencies. Even when there is no direct contact. Looking excellent though. The precision of your cutting never ceases to amaze me! (and I'm aware this is a test piece!!) Alastair M Link to post Share on other sites More sharing options...
Ceptic Posted October 16, 2012 Share Posted October 16, 2012 Many thanks 4360 (a 4 SUB number, I believe!) for taking the time and trouble to compile that list........Snip....... Any views of the windows in close-up are useful as the drawings have them a little squarer than general views of the HALs suggest. Thanks again, Colin Hi Colin. A somewhat grainy pic showing Bulleid (Not Bill Gates') windows. Referring back to my drawings of yesteryear, the corner radii of the side-lights and the base of the doors' drop-lights were approx. 4 1/2" rad. The top of the doors' drop-lights were slightly larger, at 5" rad. A dimensioned pic. to follow. Regards. Link to post Share on other sites More sharing options...
Colin parks Posted October 16, 2012 Author Share Posted October 16, 2012 Colin, Be very very careful about using any form of superglue anywhere near your transparencies. Even when there is no direct contact. Looking excellent though. The precision of your cutting never ceases to amaze me! (and I'm aware this is a test piece!!) Alastair M Hi Alastair, Thanks for the warning. I take it by 'transparencies' you mean glazing. Well, on the recent 4 CIG project, over 100 pieces of glazing were fixed with superglue! "What about the white bloom?" I hear you ask. Well I get away (and it is getting away with murder really) with superglueing glazing by applying the tiny drops just in the corners of the glazed area using the point of a pin. With each drop, I breathe hard onto it for about 5 seconds. The moisture in the breath is enough to rapidly accelerate the curing process *(and might even be blowing away the fumes). It does work well and a week ago, when one glazed piece needed to be replaced on the 4 CIG due to a paint stain caused by weathering, it was a devil of a job to release the part. That was quite reassuring. Re. cutting. Even with a blunt knife (too mean to change it for an experiment!) I found cutting windows in 10 thou. plastic sheet much easier than the thicker stuff I have used in the past. Another use of good old superglue is for repairing window corners if the knife has damaged them. It's great stuff and the repairs can be made good the same day. All the best, Colin Link to post Share on other sites More sharing options...
Colin parks Posted October 16, 2012 Author Share Posted October 16, 2012 Hi Colin. A somewhat grainy pic showing Bulleid (Not Bill Gates') windows. Referring back to my drawings of yesteryear, the corner radii of the side-lights and the base of the doors' drop-lights were 4 1/2" rad. The top of the doors' drop-lights were slightly larger, at 5" rad. A dimensioned pic. to follow. Regards. Hi Frank, Is there anything you haven't a picture of?! A great help to see the picture, which confirms what I thought; the drawings show the windows much too 'square' at the corners. Mike King's drawing does show the door drop lights correctly with a lower bottom edge than the fixed panes either side. This is a detail I got wrong on my Bulleid 2 HAPs - grrr. All the best, Colin Link to post Share on other sites More sharing options...
Miss Prism Posted October 16, 2012 Share Posted October 16, 2012 I had thought of drilling holes in the laminations to vent off any trapped solvents. When I've done this (I think I was using a 20 thou top covering 1.5mm-ish holes), all looked well at first, but after a while, telltale dimples appeared on the top surface where the holes were located, so I think the drilling holes method is definitely tempting fate with a 10 thou top surface. The amount of solvent used seems to be a critical factor. When laminating sheets, I now generally favour scrawking them with fine grooves in an attempt to provide some solvent-venting routes. Link to post Share on other sites More sharing options...
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