scanman Posted February 24, 2011 Share Posted February 24, 2011 Hi Steve - What are you using for the gap filler? if not already considered/used - I'd think about 'Superfine Milliput'. it has a good hold on small gaps and can be smoothed whith a damp rag. With regard to maintaining straight runs, I tape down a steel straightedge & butt the sleepers to it, holding the run in place with small amounts of masking tape. Depends of course how you build them - I go for the 'half-ladder' approach building the length on a jig with rail only on one side, glueingdown agaist the straightedge then attaching the second rail to gauge. Mind you I'm working in 'EM' with (at the mo') C&L products. Looking good tho' ! Regs Ian 2 Link to comment Share on other sites More sharing options...
Chrislock Posted February 24, 2011 Share Posted February 24, 2011 I attach a photo of my last turnout using Code 40, PCB and some easitrac. Apologies (as always) for my shocking soldering. Pardon me deviating from your excellent thread Steve - but a question for Pete: If you don't use chairs, how do you make the PCB rail height the same, as the association sleepers I have are not the same thickness - or am I missing summat obvious? I have inserted the odd PCB sleeper to strengthen my easitrac points, and have had to glue a strip of thin plasticard underneath so that the PCB sleepers are the same thickness as the easitrac ones. Chris 1 Link to comment Share on other sites More sharing options...
Chrislock Posted February 24, 2011 Share Posted February 24, 2011 Well, that's the progress for now - nothing spectacular, but steady progress nevertheless. Steve, That's a good deal done really in terms of hard slog, surely? I am finding your trials and tribs over easitrac very interesting. I have used the milled bases and have still ended up slotting in pbc sleepers here and there to strengthen - but thats probably down to my shoddy workmanship! Your work looks pretty neat to me. Would you mind if I mail you off thread about wiring turnouts - I have a couple of dumb questions to ask? I know what you mean about using close ups to show up flaws opportunities for improvement though. Ever thought too thast 2mm/N is not intended to be viewed so close up?!! Chris 2 Link to comment Share on other sites More sharing options...
RMweb Gold Donw Posted February 24, 2011 RMweb Gold Share Posted February 24, 2011 Steve nice work. Regarding the alignment of the straight bits, could you find a suitable length of wood. Also if you use the rail in 50cm lengths and do one half in the jig and then move it along to do the second half file a notch for the rail joint it would cut the problem in half. Alternatively pin down a piece of thin wood along the sleeper edge on the plan then fix each section down against it. When you remove the wood all should be fine. Chris could you use a bit of brass shim to hold the rail off the PCB to match the height of chaired bits. Regards Don 2 Link to comment Share on other sites More sharing options...
Pilgrimsjulie Posted February 25, 2011 Share Posted February 25, 2011 Well I must admit I am really pleased with the progress . It is so nice to see some more of the track being laid.....I never really realised in how much hard work it is in having something as spectacular as this and I know it will be great when it will see some trains running on it . I will be really pleased when I can get started on the scenery . Well not much will be done on it for a few days as the modelling room is having to be made into a dining room again , but not for long!! Link to comment Share on other sites More sharing options...
SteveBedding Posted February 25, 2011 Author Share Posted February 25, 2011 Morning all and thanks for the feedback; I'm glad people still find this of interest. To answer each point in turn... What are you using for the gap filler? if not already considered/used - I'd think about 'Superfine Milliput'. it has a good hold on small gaps and can be smoothed whith a damp rag. With regard to maintaining straight runs, I tape down a steel straightedge & butt the sleepers to it, holding the run in place with small amounts of masking tape. Depends of course how you build them - I go for the 'half-ladder' approach building the length on a jig with rail only on one side, glueingdown agaist the straightedge then attaching the second rail to gauge. Mind you I'm working in 'EM' with (at the mo') C&L products. Ian, I used a proprietary DIY surface filler. Two reasons - 1) thought process was 'hole needs filling - therefore use filler' (mental link probably DIY related rather than modelling ), and 2) it was immediately to hand. In all honesty when I was doing it, my gut feel was that it probably was not the best approach but it I didn't think it through fully... Thanks for the tip on the 'Milliput' though, I'll look some out and have a crack at using this. Another 'absence of thought' moment was in not using a straight edge to align the sleepers. On board 3, the points were on a curve and I laid the sleepers 'by eye' onto the template on the board, and I carried this process over to the straight points here - a case of not seeing the wood for the trees, it wasn't until I stepped back and took the photos did I see that the were several misaligned sleepers. Good news is that I had a quick look and there are only about a dozen sleepers that need fettling to 'straighten' the edge. On the up side, there are only 3 points on board 1, and thankfully 2 of them are curved - I've come to the conclusion that I really don't like straights! Lastly, I'm going to use the 'half-ladder'/jig approach for one of the sidings. The siding on the north side of the loading dock (nearest the platform) retained the original flat-bottom rail inset in brick and concrete. I can't use Easitrac for this one so will revert to the traditional approach. Steve, That's a good deal done really in terms of hard slog, surely? I am finding your trials and tribs over easitrac very interesting. I have used the milled bases and have still ended up slotting in pbc sleepers here and there to strengthen - but thats probably down to my shoddy workmanship! Your work looks pretty neat to me. Would you mind if I mail you off thread about wiring turnouts - I have a couple of dumb questions to ask? I know what you mean about using close ups to show up flaws opportunities for improvement though. Ever thought too thast 2mm/N is not intended to be viewed so close up?!! Chris Chris. Thanks, fire away with your question. I've come to the conclusion that when this gets out & about, I'll set viewing barriers about 8'-10' away from the layout - that should hide the details . Of more concern is the difference between what I see with the Mk1 eyeball, and what the camera tells me is really there Steve nice work. Regarding the alignment of the straight bits, could you find a suitable length of wood. Also if you use the rail in 50cm lengths and do one half in the jig and then move it along to do the second half file a notch for the rail joint it would cut the problem in half. Alternatively pin down a piece of thin wood along the sleeper edge on the plan then fix each section down against it. When you remove the wood all should be fine. Don, thanks for the ideas on the wood strip. Like my earlier response to Ian, I completely overlooked that approach I don't have an Easitrac track jig, and my understanding is that even that wont help in laying straight section; I know that Easitrac can be laid in 50cm lengths, but I've tried to keep section lengths to a maximum of 250mm to ensure that there were sufficient expansion joints. My thoughts are that Easitrac may be more susceptible to heat expansion/movement than 'rail on PCB' because of the nature of the rail floating in the chairs - the PCB approach may provide more 'resistance' to such movement (this is my thinking and may not be representative of others experience/knowledge). Looking back at what I'd done, I think the problem was where I finished one section of track (the breaks in the rail being placed in the middle of a sprue of 6 sleepers) I had glued down all of that last sprue before I'd got the next track section ready. I'm using the Easitrac PVA and this does dry very quickly! I'd assumed that laying a straight length of track would be simple . The learning point from this is to prepare all the sections for a length, or a run of track, before commencing the glueing! Well not much will be done on it for a few days as the modelling room is having to be made into a dining room again , but not for long!! Damn! Now you see the hardships that I have to put up with... Be back soon 1 Link to comment Share on other sites More sharing options...
RMweb Gold bcnPete Posted February 25, 2011 RMweb Gold Share Posted February 25, 2011 Steve, Very nice progress. It's really starting to come together now and I can't wait to see that Blue 24 test engine giving this board the once over. I do think the additional PCB sleepers in the mix will be a good long term decision in terms of durability/further tweaking. To side track slightly onto Chris's question from above - I can't remember what I did with the differing heights The most recent trackwork I built, I just threaded the code 40 through the plain easitrac, ran it across the PCB's, and back into the plain easitrac again. I then used my ham fisted soldering to hold it all together...all seems to work ok at present. Well not much will be done on it for a few days as the modelling room is having to be made into a dining room again In that case, see you back here straight after dinner then...not to many glasses of cognac and cigars mind...there's still plenty of work to be done 2 Link to comment Share on other sites More sharing options...
RMweb Premium Kris Posted February 26, 2011 RMweb Premium Share Posted February 26, 2011 Good to see the progress that you are making here Steve. Regarding the tracksetta, why not just add a shim on brass that is .4mm wide to the edge of one? 1 Link to comment Share on other sites More sharing options...
SteveBedding Posted February 26, 2011 Author Share Posted February 26, 2011 ...Regarding the tracksetta, why not just add a shim on brass that is .4mm wide to the edge of one? Thanks Kris - such a blindingly obvious & simple solution! There's me looking for ways to mill out strips 9.42mm when I've got a large piece of 0.4mm PCB - I'll just cut off a strip and use it as a shim! Cheers 1 Link to comment Share on other sites More sharing options...
RMweb Gold queensquare Posted February 26, 2011 RMweb Gold Share Posted February 26, 2011 Thanks Kris - such a blindingly obvious & simple solution! There's me looking for ways to mill out strips 9.42mm when I've got a large piece of 0.4mm PCB - I'll just cut off a strip and use it as a shim! Cheers Ever the bodger, I used an idea which came from, I think, Kieth Armes (definately not a bodger) whereby I went along the centreline of a tracksetta with a large centre punch and a hefty hammer. That was enogh to spread it by about .4mm. Jerry 2 Link to comment Share on other sites More sharing options...
SteveBedding Posted February 26, 2011 Author Share Posted February 26, 2011 Ever the bodger, I used an idea which came from, I think, Kieth Armes (definately not a bodger) whereby I went along the centreline of a tracksetta with a large centre punch and a hefty hammer. That was enogh to spread it by about .4mm. Jerry What a picture that conjures! I can just imagine some finescale purists having kittens over that idea, but I can see just how it would work.. However, the thought of close association of my fingers and thumbs to a 'hefty hammer' may just change the vernacular use of the "F" in 2FS On the up side, the swear box may suddenly cover one of the promised Dapol Halls (SWMBO note hint... ...you wanted birthday suggestions ) 1 Link to comment Share on other sites More sharing options...
2mm Andy Posted February 26, 2011 Share Posted February 26, 2011 To side track slightly onto Chris's question from above - I can't remember what I did with the differing heights The most recent trackwork I built, I just threaded the code 40 through the plain easitrac, ran it across the PCB's, and back into the plain easitrac again. I then used my ham fisted soldering to hold it all together...all seems to work ok at present. You could use chairplates inserted between rail and pcb sleeper. The 'Versaline' ones should be suitable (I think that's what I used on the milled pcb baseboard joint pieces on my layout). You'll need to be quick with the soldering iron to avoid the chance of melting the Easitrac sleeper bases though (or clamp some sort of heat sink in place - a roller gauge might do) Andy 1 Link to comment Share on other sites More sharing options...
SteveBedding Posted February 26, 2011 Author Share Posted February 26, 2011 You could use chairplates inserted between rail and pcb sleeper. The 'Versaline' ones should be suitable (I think that's what I used on the milled pcb baseboard joint pieces on my layout). You'll need to be quick with the soldering iron to avoid the chance of melting the Easitrac sleeper bases though (or clamp some sort of heat sink in place - a roller gauge might do) Andy I fully agree with Andy on this, I've used the Versaline chair plates (or 10thou brass strip for the 'longer' chairs) and although I wasn't always 'quick' with the iron, I always kept the roller gauges on either side of the bit being soldered. Additional benefit here was that it made very sure that the rails being soldered were kept in gauge. 1 Link to comment Share on other sites More sharing options...
scanman Posted February 27, 2011 Share Posted February 27, 2011 I will be really pleased when I can get started on the scenery . Well not much will be done on it for a few days as the modelling room is having to be made into a dining room again , but not for long!! Scenery. My favourite ocupation - its when the layout (blue diseasels not withstanding) really *does* come to life. As to having to reclaim the dining room, wots wrong with trays on laps??? Regs Ian 1 Link to comment Share on other sites More sharing options...
RMweb Premium nick_bastable Posted February 27, 2011 RMweb Premium Share Posted February 27, 2011 Steve I have used plastic putty to fille the gap in the sleepers, worked well for me and can be eaily sanded down although i normally thin the putty with liquid-polly. 1 Link to comment Share on other sites More sharing options...
RMweb Gold bcnPete Posted February 27, 2011 RMweb Gold Share Posted February 27, 2011 (blue diseasels not withstanding) Steady...you can go off people you know 2 Link to comment Share on other sites More sharing options...
Pilgrimsjulie Posted March 2, 2011 Share Posted March 2, 2011 Well SWMBO has seen the hint for the birthday present and yes I will get you a Dapol Hall when one is about. Not only that but I will get you the Western as well but I think there will have to be 2 one in green and one in blue - I wouldn't want to disappoint the other RMWeb readers as well would I !! Well with your going to the Abingdon show on Saturday I will let you get one if you do manage to see any!!!! Remember its my money though!!! Well no doubt now that we are back to it being just the two of us the dining room will soon be disappearing to the model room again so the meals will be back to having trays again!! Link to comment Share on other sites More sharing options...
scanman Posted March 4, 2011 Share Posted March 4, 2011 Well SWMBO has seen the hint for the birthday present and yes I will get you a Dapol Hall when one is about. Not only that but I will get you the Western as well but I think there will have to be 2 one in green and one in blue - I wouldn't want to disappoint the other RMWeb readers as well would I !! Well with your going to the Abingdon show on Saturday I will let you get one if you do manage to see any!!!! Remember its my money though!!! Well no doubt now that we are back to it being just the two of us the dining room will soon be disappearing to the model room again so the meals will be back to having trays again!! Nothing wrong with trays (or blue diesels come to that) ian 1 Link to comment Share on other sites More sharing options...
SteveBedding Posted March 4, 2011 Author Share Posted March 4, 2011 The track laying is progressing, albeit at a snails pace, and now I’ve reached a position where I have got to get the mill out and make some more sleeper strips for the board joints. The thought of the ‘production line’ to make the next batch of points is daunting; two was challenging enough but 9 in quick succession…! A diversion is required! I have always been very impressed with Missy’s 57xx; not only does it look superb with the way in which the basic Farish body has been detailed, but it runs particularly well. As I’ve always said, I’m not above plagiarising/steeling any good ideas, and was very grateful when she lent me the loco, and a spare set of frames to reverse engineer. There are some very good articles and resources available through the Association which explain the construction of split-frame chassis and the way in which gear ratios and drive trains can be calculated; but designing from first principles is made a lot easier if a tangible ‘end-state’ can be seen. It's the little details such as replacing the moulded handrails on the Farish casting with proper wire ones, the use of proper 'toolboxes', and the detailed pipework forward of the cab, that make this a model worthy of copying; additionally, the design replaces the clunky footplate cast with the body to a much finer one that is a part of the chassis. The photo below shows how neatly the motor, gear train, and decoder all fit together into a very compact space. The frames themselves are simply cut from 0.6mm double-sided PCB, but are nicely detailed to reflect/simulate the profile of the actual prototype and its 'springing' of the wheels. The first consideration is what top-speed/how fast does the loco want to go? This sets the parameters for the choice of motor and the gear reduction ratio; additionally, I want to see ‘daylight’ under the boiler, so this impacts the size and shape of the chosen motor. In real terms, the choice of motor is actually quite straightforward as this has been done may times in the past; the motor of usual choice is the Faulhaber 0816 coreless 6v motor. This small motor physically fits easily within the confines of the Farish body and is sufficiently powerful for a small shunting engine. Whilst this is an excellent piece of engineering, its downside is the price; at around £50 (Including shipping etc) it is somewhat pricey for a first experiment, so an alternative needs to be found. The Nigel Lawton range of small coreless motors immediately spring to mind and the 10 Volt 8mm x 16mm Midi Motor (DCC compatible) appeared to fit the bill exactly. It has the same physical dimensions and the no-load speed is 97% (16,000rpm vs 16,500rpm) of that of the Faulhaber. Further it has a higher input voltage (10v against 6v) so should be resilient to ‘ham-fisted’ over-driving… With the motor chosen and its no-load speed known, the gear reduction needs to be calculated to achieve the desired top speed of the loco. The locos will be required to pull a small branch line passenger service, a mixed goods service of up to a dozen wagons, and to act as a station pilot – therefore not a lot of ‘high speed’ use, but precise control for shunting is required. This caused some concern as I was unable to find a definitive top speed for the 57xx/8750, so some pragmatic subjective assessment was required (OK, I guessed! ) and a reasonable figure in the range of 45mph-50mph was decided on. There is a set of formulae that can be applied to calculate the necessary gear reduction which use the motor speed, scale, wheel diameter and rpm. These are not particularly complex, but since someone has already done the hard work, why reinvent the wheel (so to speak…); there is a very simple to use Scale Speed Calculator developed by the Wealden Area Group of the Association that does all the hard work for you NOTE: One key point here is that whilst the speed of the motors is usually given as a ‘No-load’ speed, these calculations should use an ‘under-load’ speed to compensate for losses/friction in the drive-chain; this is normally taken as: Under-load Speed = 75% of No-load Speed. Using the Speed Calculator utility, with a motor speed of 12,000 rpm (75% of 16,000), a wheel diameter of 9mm (drive wheels of a 57xx are 4’7.5â€), and target speed of 45mph to 50mph… …the necessary gear reduction will fall in the range of 39:1 and 43:1. This is now where some thinking is required. Missy’s design calls for a 2-stage reduction, which I think is quite a common approach and an example is given in the “Suggested dimensions for loco chassis construction†on the Association web site. In fact the example shows a 30:1 worm drive from the motor, followed by a 28:20 reduction to the wheels; 30:1 x 28:20 gives 30 x 1.4, which equals a 42:1 reduction – Oh what a surprise, that’s almost exactly what is wanted… Just as a thought, there is a 21T gear in the Association 100DP range, and if this is substituted for the 20T, this gives a reduction of 30:1 x 28:21 = 30 x 1.3333 = 40:1 reduction which is again within the target range. The decision is to use the 42:1 reduction (30:1 worm and 28:20) for the 57xx/8750 chassis as this is closest to the 45mph top speed. Something that wasn’t obvious from this approach (and fortunately not an issue this time) is to make sure that the choice of the final gear actually fits the drive wheel. In this case the outside diameter of the 28T 100dp gear is 7.62mm which is less than that of the drive wheel (9mm) – if a smaller wheel was used, or a larger gear needed, this could be a problem and should be considered. This is one of those things that in hindsight is glaringly obvious but easily overlooked – thanks to the Association VAG for pointing this pitfall out. With the motor and gear train decided, it becomes a simple (?) task to apply the correctly sized components onto a scale drawing of the 57xx/8750… … the critical dimensions here are the meshing distances between the 28T and 20T gears (6.1mm) and the 30:1 worm (5.46mm). The position of the wheels is obviously fixed, but the actual location of the motor, and intermediate gear is adjustable (within the confines of the body) so long as the critical meshing dimensions are maintained. Well, that’s the concept and a run through from first principles. At this point I’ll go back to precisely measuring Missy’s frames and see if I’m on the right track! 4 Link to comment Share on other sites More sharing options...
RMweb Premium Kris Posted March 4, 2011 RMweb Premium Share Posted March 4, 2011 Looks like you'll have a new loco running soon ish. 1 Link to comment Share on other sites More sharing options...
RMweb Gold Donw Posted March 4, 2011 RMweb Gold Share Posted March 4, 2011 Very nice explanation there Steve. 45-50mph sounds reasonable certainly on the Calne branch and most definately within the station area. The 57xx could turn a reasonable speed there was a case of one which had to pilot a deisel in trouble. Part way through the deisel cames back to life and started pushing the 57xx. I have a similar excercise to go through if I build a new chassis for the terrier. Seeing as they are practically the only wheels left in stock I have ordered a set plus a number of gears. 4ft wheels are a bit limiting on gear size though. Chassis are not my forte though I would rather build nine points than one chassis so I will probably leave it for a bit. I do have an old 94xx which has a scale chassis (well the wheels are scale not sure about the wheelbase) its been in store for 25 years I hope nothing's rusted up. Don 1 Link to comment Share on other sites More sharing options...
Gingerbread Posted March 4, 2011 Share Posted March 4, 2011 Good to see the pannier project progressing I'd suggest looking at the possibility of raising the motor by about a millimetre (which should put it fairly close to the centreline of the boiler), and moving it about a millimetre to the right. Adjust the intermediate gear by a similar amount to match. This would give you the chance of some daylight below the boiler, which looks difficult with your current placement. David 1 Link to comment Share on other sites More sharing options...
SteveBedding Posted March 4, 2011 Author Share Posted March 4, 2011 I'd suggest looking at the possibility of raising the motor by about a millimetre (which should put it fairly close to the centreline of the boiler), and moving it about a millimetre to the right. Adjust the intermediate gear by a similar amount to match. This would give you the chance of some daylight below the boiler, which looks difficult with your current placement. David Thanks for the observation; you are quite correct in that there is some more fine tuning needed of the positioning of the motor and intermediate gear - this was only a first pass to see the 'art of the possible'. Having got to this point, I wanted to draw up Missy's frames and match them up against my initial positioning to see where the discrepancies were (this is a work in progress but I hope to get it complete on Sunday...) Looking at the earlier picture of the completed chassis, it appears that the 'front' of the motor starts almost at the end of the leading splasher which would imply that the motor needs to move about 3-4mm towards the rear, also, as you suggested, the motor could be raised about 1mm higher, but I need to measure the available height in the Farish casting (and see if there is any scope for 'thinning' the top) before this can be confirmed. As to the 'daylight under the boiler', this was rather a misleading aspiration, as this picture of an 8750 shows... ... the only 'daylight' is just visible between the leading and driving wheels, but the insides of the frames are more easily visible and I think this is a more achievable aspiration 2 Link to comment Share on other sites More sharing options...
Andrew Peters Posted March 6, 2011 Share Posted March 6, 2011 Looks good Steve, will have to watch this closely as I'll have to have the odd 1 or 2 for mine then 1 Link to comment Share on other sites More sharing options...
RMweb Gold bcnPete Posted March 6, 2011 RMweb Gold Share Posted March 6, 2011 Nothing wrong with trays (or blue diesels come to that) even better then that...a blue diesel on a tray...who needs TV dinners when you can have this? Steve, A fascinating read on the pannier project... Watching with great interest as I have a friend with a BR(WR) 2mmFS layout who was talking of creating a steam special last year...using a converted pannier tank...I will report to him immediately... 1 Link to comment Share on other sites More sharing options...
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