Horsetan Posted February 1, 2016 Share Posted February 1, 2016 Is there something I should know about the coupling rods that come with the chassis kit? Dave Bradwell's 9F rods are fine. Link to post Share on other sites More sharing options...
Killybegs Posted February 1, 2016 Author Share Posted February 1, 2016 No John, not at all. I just thought Bill's coupling rods and the way they were jigged to go together was a really good idea. What you can't see on the photo on Eileens site are the holes in the etches that line everything up. You might find this collection of photos of some use. https://goo.gl/photos/kBZbgnYECRZyaF4EA Let me know if you can't access them. Mike Thanks for the photos Mike. Bill's coupling rods look less complicated than those in the kit. I may get some, make up both sets, then decide which to use. Link to post Share on other sites More sharing options...
Dave Holt Posted February 2, 2016 Share Posted February 2, 2016 I'd stick with Dave's rods. At least you can be certain they're etched for the same wheelbase as the frames. Link to post Share on other sites More sharing options...
Killybegs Posted February 2, 2016 Author Share Posted February 2, 2016 I'd stick with Dave's rods. At least you can be certain they're etched for the same wheelbase as the frames. I'm inclined to agree with you but I might get a set of BB's rods to compare them before I set the chassis up. Link to post Share on other sites More sharing options...
Killybegs Posted February 2, 2016 Author Share Posted February 2, 2016 Leaving aside coupling rods for the time being, I have been getting with the bits of the chassis kit that need modifying as well as fabricating some that aren't included. The lower section of the firebox is part of the Bachmann chassis casting, so I have had to make a new one from styrene. 0.4mm brass wire has been used to add detail. I have used only one of the three components included in the kit Bachmann to make up the ashpan as I don't need a front or back. I also had to shorten the top a little as the body casting clashes at the rear. The n/s ashpan is pinned and superglued to the underside of the firebox and, in due course, will be soldered inside the frames, hence no primer on the bottom section. The preliminary coat of primer is good for showing up those areas that need filling. 13 Link to post Share on other sites More sharing options...
Killybegs Posted February 6, 2016 Author Share Posted February 6, 2016 Having built the lower section of the firebox, the next task was to do the same thing with the boiler. This was drawn up on the computer and cross sections taken at 12mm intervals. Why 12mm? The boiler is approximately 72mm long and that seemed a sensible division. The basic structure comprises four layers of 1.5mm thick styrene. The first layer is cut to fit inside the upper boiler and the other three are cut to a size that reduces the amount of 'carving' to the minimum. This was left to harden for 24 hours, during which time I cut out some profiles from 0.75mm styrene ready for the shaping process. The boiler and smoke box were made as one unit. Initial shaping involved carving with a scalpel, followed by scraping with same and finally finishing off with a sanding stick. The underside of the boiler will be fixed to the body but the firebox will be fixed to the chassis. To overcome the sloping face of the firebox preventing the body from slipping neatly onto the chassis, the rear section of the boiler was sawn off and fixed to the front of the firebox. The cut was made on the line of a boiler band which itself hides the join between the two sections of the boiler. Boiler bands were cut from 0.125mm styrene ans secured with solvent. Once the boiler is secured in place, I will make up extensions to the support brackets moulded onto the underside of the footplate. 4 Link to post Share on other sites More sharing options...
mike morley Posted February 6, 2016 Share Posted February 6, 2016 One useful tip I was given long ago by Castlefinn of this parish was to use alternate black and white layers of plastic when building up laminates. It makes it much, much easier to see how even (or not) things are when doing the shaping and smoothing. Link to post Share on other sites More sharing options...
Killybegs Posted February 6, 2016 Author Share Posted February 6, 2016 One useful tip I was given long ago by Castlefinn of this parish was to use alternate black and white layers of plastic when building up laminates. It makes it much, much easier to see how even (or not) things are when doing the shaping and smoothing. The only problem with that is that, in my experience, black styrene tends to be softer than white, which can make it difficult to get a clean finish. Link to post Share on other sites More sharing options...
Jock67B Posted February 7, 2016 Share Posted February 7, 2016 Evening John, My goodness what painstaking workmanship, this is really going to look special from any angle!! Kind regards, Jock. Link to post Share on other sites More sharing options...
Killybegs Posted February 9, 2016 Author Share Posted February 9, 2016 (edited) I have been ploughing on working my way through the list of changes to the body (now approaching 30!). Today I have been thinning down the boiler bands. The photos below (particularly the one of the junction between boiler and smokebox) show how much has had to come off. It's a long slow job with a No 10 scalpel blade and some very fine abrasive sticks. The handrails came off to make it easier, as did the regulator rod. These were coming off anyway, the former to have their knobs replaced with finer ones and the latter to be replaced by a scratch built brass alternative. The Bachmann regulator rod is plastic and seems to be bent on most examples. I also removed the raised surrounds to the handrail knobs as these don't seem to appear on the prototype. One smoke deflector handrail knob broke off and had to be drilled out, fortunately it was some sort of soft metal. I also drilled out the chimney and tidied up the capping while I was at it (after the first photo was taken!). Edited February 9, 2016 by Killybegs 8 Link to post Share on other sites More sharing options...
Jock67B Posted February 9, 2016 Share Posted February 9, 2016 Usual close attention to detail John, most impressive! Kind regards, Jock. Link to post Share on other sites More sharing options...
Kempenfelt Posted February 12, 2016 Share Posted February 12, 2016 Excellent work as always John! Out of all the mod's you've been making though, what a difference thinning those boiler bands make! I didn't expect that mod alone to make such a big difference! This has got all the makings of a very fine model, will be very interested to see how Morgan gets on with the wheels. Best Wishes Paul Link to post Share on other sites More sharing options...
Killybegs Posted February 12, 2016 Author Share Posted February 12, 2016 Yes, well worth the effort. Yesterday I was working on improved sand fillers as I was not happy with the ones on the model. Fortunately, back in the mists of time when I had no reason to suppose I would need a 9F (I hadn't long started work on Clinkerford), I took a few photographs of a couple of 9F's at the Midland Railway Centre, one in the process of being rebuilt but sans boiler, the other still being stripped down. One showed the new sandboxes, the other showed the original filler pipes. What is very clear from those photographs (and I now see from those in books), is that the footplate butts up against the boiler, no gaping gap as on the model. Once I have fitted the bottom to the boiler (and that means sorting out the amount and positioning of added ballast), I will fill the gap with styrene and filler. I have already filed out the necessary openings in the metal footplate for the sand pipes and they will act as a guide when drilling through the filled gap. Next job, however, is sorting out the handrails and reverser rod in case I need to access the inside of the boiler to secure the fixings. 3 Link to post Share on other sites More sharing options...
Dave Holt Posted February 12, 2016 Share Posted February 12, 2016 John, Very nice work so far - I especially like the look of the lower boiler extension. I presume Bachmann made this part of their chassis block? Regarding the foot plate/boiler gap, I doubt they actually touched as this would lead to chafing of the boiler cladding. Locos with thin foot-plating, like BR standards and our modified MN, have the inner edge of the footplate turned up by about 1" to 1 1/2", to give some stiffness (you can still feel it flex as you walk along!). This brings the top edge closer to the curve of the boiler cladding and makes the gap look less. I agree there shouldn't be a gaping space between. Looking forward to following further progress. Dave. Link to post Share on other sites More sharing options...
Porcy Mane Posted February 12, 2016 Share Posted February 12, 2016 Fantastic work so far. I'm interested to see how how you're going to sort the top firebox/boiler interface that I harped on about here: http://www.rmweb.co.uk/community/index.php?/topic/37407-9f-info-please/&do=findComment&comment=1905609 I've never sussed out how Bachmann missed that error as they look to have got the other BR standard and Ivatt smokeboxes correct. P Link to post Share on other sites More sharing options...
45609 Posted February 12, 2016 Share Posted February 12, 2016 John, Very nice work so far - I especially like the look of the lower boiler extension. I presume Bachmann made this part of their chassis block? Regarding the foot plate/boiler gap, I doubt they actually touched as this would lead to chafing of the boiler cladding. Locos with thin foot-plating, like BR standards and our modified MN, have the inner edge of the footplate turned up by about 1" to 1 1/2", to give some stiffness (you can still feel it flex as you walk along!). This brings the top edge closer to the curve of the boiler cladding and makes the gap look less. I agree there shouldn't be a gaping space between. Looking forward to following further progress. Dave. Like this.... Link to post Share on other sites More sharing options...
JeffP Posted February 12, 2016 Share Posted February 12, 2016 Nice pic! Link to post Share on other sites More sharing options...
Killybegs Posted February 12, 2016 Author Share Posted February 12, 2016 John, Very nice work so far - I especially like the look of the lower boiler extension. I presume Bachmann made this part of their chassis block? Regarding the foot plate/boiler gap, I doubt they actually touched as this would lead to chafing of the boiler cladding. Locos with thin foot-plating, like BR standards and our modified MN, have the inner edge of the footplate turned up by about 1" to 1 1/2", to give some stiffness (you can still feel it flex as you walk along!). This brings the top edge closer to the curve of the boiler cladding and makes the gap look less. I agree there shouldn't be a gaping space between. Looking forward to following further progress. Dave. The camera never lies. The bottom of the footplate is tight against the boiler bands which means the upstand must lean over to follow the profile of the boiler. Morgan's photo is of a preserved example. Even as built, the upstand seems to have varied in height between locos. There were also differences in the design and size of the support plates for the sand pipes. Early locos appear to have had plain sheet while later ones had the ribbed style shown in Morgan's photo. So it's a case of pick your prototype and stick with it. You are quite right, Bachmann did make the bottom of the firebox part of the chassis block. Porcy, the top of the firebox/boiler will probably stay as it is but now that you have mentioned it, who knows! Link to post Share on other sites More sharing options...
Killybegs Posted February 12, 2016 Author Share Posted February 12, 2016 Just to complete the picture, so to speak, here are a couple of shots of 92214, showing the sandboxes themselves and a lot of other stuff. The rest of my pics are mostly of the valve gear and pony truck on 92214. And talking of wheel hubs, what about this one ..... 3 Link to post Share on other sites More sharing options...
Dave Holt Posted February 12, 2016 Share Posted February 12, 2016 (edited) The camera never lies. The bottom of the footplate is tight against the boiler bands which means the upstand must lean over to follow the profile of the boiler. Morgan's photo is of a preserved example. Even as built, the upstand seems to have varied in height between locos. There were also differences in the design and size of the support plates for the sand pipes. Early locos appear to have had plain sheet while later ones had the ribbed style shown in Morgan's photo. So it's a case of pick your prototype and stick with it. You are quite right, Bachmann did make the bottom of the firebox part of the chassis block. Mmmm. Your photo is definitely an original, ex-Barry condition example, is it? If so, it looks to me as if this particular example had flat running boards with the upstand welded on the top, set in from the edge to clear the boiler cladding. It wouldn't lean over, I'm sure. We made a bit of ours on P&O like that, where it follows the front of the firebox throat plate. Two different methods of manufacture (folded or welded) may also explain the different height in upstand you mention? Different works methods? Anyway, it would be much easier to model it that way, anyhow. I think the "boiler bands" you refer to are actually the crinolines which support the cladding sheets and hold them away from the boiler to leave space for lagging. Dave. Edited February 12, 2016 by Dave Holt Link to post Share on other sites More sharing options...
45609 Posted February 12, 2016 Share Posted February 12, 2016 (edited) John has very kindly given me permission to drop in and show what I'm getting up to in support of this 9F project. I mentioned earlier that I had a cunning plan to obtain some wheels that actually look like 9F wheels and not like modified Ivatt 2MT wheels. Having followed the link that Porcy posted earlier and an onward link from there I came across this pipe dream. We all know Horse is a bit mad but frankly I'm madder so I'm actually going to give this a go. I will be reusing the Bachmann wheel centres. Preparing and fitting Alan Gibson tyres. Modifying the wheel centres to suit a suitable crankpin. Making and drilling new 1/8" axles with a prototypical hole. Finally boring the wheel centre holes to be a press fit on the axles. Now there is quite a bit to do. It is almost a series of projects within a project so I will take it a step at a time and write a bit now and again as I make progress. So, tonight is Friday night and that means it is experiment night.....but first a bit more explanation. I figured there were two broad approaches to doing these wheels. The Alan Harris method, using a Tufnol bush between the wheel centre and axle then press fitting the tyre to the wheel centre or, what I'm calling, the Tony Reynalds method because he explained it to me a couple of weeks ago. The major problem with the AH method, in the context of the 9F, is it will leave you with a live crankpin and as a consequence a non running loco as both sides will be electrically connected via the coupling rods > con-rod > cross head > cylinder block path (and multiple other paths if you think about it). The crankpins would need to be isolated from the wheel centre which might be ok on 7mm but on 4mm.....!?! The TR approach is to lay up some slow setting Araldite into the I/D lip/bore of the tyres and cure it in the oven for 30 mins at 100degC. He did say that the glue will slump a little but should leave enough of a coating that can be machined out to square it up. The wheel centres are then machined to be a sliding fit in the bore of the Araldite coated tyres and glued in place. Today I wondered if I could improve this aspect slightly and I trialed a slight refinement of this process using my favourite pastime. Misuse of industrial equipment for personal projects. Using the 3D printer at work I made a simple jig/mould to hold the ID lip of the tyres so that I could dribble a bead of Araldite into place and avoid, as much as possible, the slump of the glue as it sets. I coated the jig well with vaseline in hope that the glue should bond to the tyres but not glue everything to the jig. I have bought a good number of tyres from Colin Seymour to allow for the various trials that will no doubt go hand in hand with this project. The tyre I/D was very well degreased with Acetone by the way. This first photo shows the starting point for the evening. The black rectangle with 10 round spigots is my 3D printed jig. If things were successful the 10 station jig would do a loco set in one go. The next two images show the tyre located on the greased up spigot and the Araldite applied to the annular gap between the tyre and spigot At this point it was into the oven for half an hour. The results looked promising as the glue was cured but the tyre was also well stuck to the jig. Far more so than I had hoped. I eventually freed it from the jig without apparently damaging the bond between the steel and the Araldite. But in removing the tyre I marked the tread in a couple of places with the tool I used to lever it free. The result has proved one thing. Araldite cured in the oven is seriously strong stuff. It looks like a 3D printed plastic jig is not going to work as intended but I have an alternative thought of which I will post more soon. If all else fails I'll have to live with the glue slump and hope I have enough thickness to true up in the lathe. That's all for now......Morgan Edited February 13, 2016 by 45609 1 Link to post Share on other sites More sharing options...
Horsetan Posted February 12, 2016 Share Posted February 12, 2016 (edited) ....We all know Horse is a bit mad but frankly I'm madder....In this world, you need to be mad in order to retain your perspective. .... so I'm actually going to give this a go. I will be reusing the Bachmann wheel centres. Preparing and fitting Alan Gibson tyres. Modifying the wheel centres to suit a suitable crankpin. Making and drilling new 1/8" axles with a prototypical hole. Finally boring the wheel centre holes to be a press fit on the axles. ....I take it this is just a one-off job for John, because I can't see you being too happy about the rest of us who have Bachmann 9F wheels (and I've got two full sets here) beating a path to your door asking for the same!! Edited February 13, 2016 by Horsetan 1 Link to post Share on other sites More sharing options...
Killybegs Posted February 13, 2016 Author Share Posted February 13, 2016 Wow Morgan, you didn't waste much time making a start on those tyres. I really appreciate the lengths you are going to in your effort to produce a really good set of 9F wheels. Keep up the good work, I wait with baited breath! Have my wheels arrived with you yet? Link to post Share on other sites More sharing options...
barrowroad Posted February 13, 2016 Share Posted February 13, 2016 Wow Morgan, you didn't waste much time making a start on those tyres. I really appreciate the lengths you are going to in your effort to produce a really good set of 9F wheels. Keep up the good work, I wait with baited breath! Have my wheels arrived with you yet? Hi Morgan, I can only repeat John's comments - Wow! Link to post Share on other sites More sharing options...
Mike G Posted February 13, 2016 Share Posted February 13, 2016 Sorry, but I can't reciprocate Robin's and John's comments, I have comments all of my own...seriously jealous ones! Mike 1 Link to post Share on other sites More sharing options...
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