AndyID Posted September 22, 2021 Share Posted September 22, 2021 17 hours ago, Compound2632 said: Thanks. So at 1:7, one would want to remove 35 mm / 37 mm to reduce the centres to 44.7 mm / 45.0 mm - that looks to require the removal of three or possibly four sleepers? Presumably the 00 fine and EM crossovers will be at prototypical centres. Except that a 1:7 isn't exactly prototypical (except in a few cases) and reducing the pitch with a 1:7 crossover will exacerbate the reverse curve problem. Link to post Share on other sites More sharing options...
RMweb Premium Compound2632 Posted September 22, 2021 RMweb Premium Share Posted September 22, 2021 32 minutes ago, AndyID said: Except that a 1:7 isn't exactly prototypical (except in a few cases) and reducing the pitch with a 1:7 crossover will exacerbate the reverse curve problem. Maybe so but there are other advantages to prototypical track centres, such as being able to model overbridges to scale. Besides, if you're not laying EM at prototypical track centres, what's the point? (If you will forgive the pun). Compromise, compromise... Link to post Share on other sites More sharing options...
hayfield Posted September 22, 2021 Share Posted September 22, 2021 3 hours ago, AndyID said: Except that a 1:7 isn't exactly prototypical (except in a few cases) and reducing the pitch with a 1:7 crossover will exacerbate the reverse curve problem. 2 hours ago, Compound2632 said: Maybe so but there are other advantages to prototypical track centres, such as being able to model overbridges to scale. Besides, if you're not laying EM at prototypical track centres, what's the point? (If you will forgive the pun). Compromise, compromise... My understanding is that there were/are minimum requirements but in many instances track centres were larger than the minimum However in railway modelling compromises are usually the norm, turnout sizes tend to be decided on space available. Few have the luxury of following the prototype and in modelling terms a B7 is quite generous Look at the uphill struggle to get the mass market to take notice of track, moving from the unprototypical RTR offerings to a B7 is massive, to EM gauge is even bigger, both these moves do actually complement the quality of the latest RTR stock offerings 4 Link to post Share on other sites More sharing options...
AndyID Posted September 22, 2021 Share Posted September 22, 2021 4 minutes ago, hayfield said: My understanding is that there were/are minimum requirements but in many instances track centres were larger than the minimum However in railway modelling compromises are usually the norm, turnout sizes tend to be decided on space available. Few have the luxury of following the prototype and in modelling terms a B7 is quite generous Look at the uphill struggle to get the mass market to take notice of track, moving from the unprototypical RTR offerings to a B7 is massive, to EM gauge is even bigger, both these moves do actually complement the quality of the latest RTR stock offerings Of course they do. My only point is it's not practical to strictly observe one prototype practice while bending another prototype practice. Modelling is all about making the compromises necessary to make the model work. 3 Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted September 22, 2021 RMweb Gold Share Posted September 22, 2021 9 minutes ago, AndyID said: Of course they do. My only point is it's not practical to strictly observe one prototype practice while bending another prototype practice. Modelling is all about making the compromises necessary to make the model work. Compression is one of the compromises. A real 15mph trailing crossover on a standard six-foot would be about 30 inches long measured to the ends of the stock rails when transferred to 4mm scale. 2 Link to post Share on other sites More sharing options...
RMweb Premium NFWEM57 Posted September 22, 2021 Author RMweb Premium Share Posted September 22, 2021 (edited) 56 minutes ago, TheSignalEngineer said: Compression is one of the compromises. A real 15mph trailing crossover on a standard six-foot would be about 30 inches long measured to the ends of the stock rails when transferred to 4mm scale. Very informative on speed vs. crossover. Is there a table of crossover sizes vs. speed limit anywhere? Update - Found a link Edited September 22, 2021 by NFWEM57 additional info Link to post Share on other sites More sharing options...
RMweb Gold TheSignalEngineer Posted September 22, 2021 RMweb Gold Share Posted September 22, 2021 (edited) 5 minutes ago, NFWEM57 said: Very informative on speed vs. crossover. Is there a table of crossover sizes vs. speed limit anywhere? I think there's one in the Permanent Way Institute book on track but can't get at my copy to look. There's certainly tables of dimensions in there. Edited September 22, 2021 by TheSignalEngineer Typo Link to post Share on other sites More sharing options...
RMweb Premium NFWEM57 Posted September 22, 2021 Author RMweb Premium Share Posted September 22, 2021 12 minutes ago, TheSignalEngineer said: I think there's one in the Permanent Way Institute book on track but can't get at my copy to look. There's certainly tables of dimensions in there. Thank you for the response. Skimming my 1964 version, only tables of dimensions, not speed restriction tables. 1 Link to post Share on other sites More sharing options...
SydTrax Posted September 23, 2021 Share Posted September 23, 2021 Although others have said the same, I'd just like to say how happy I was with the kit I ordered. I bought one a few weeks back, just to give it a go and see how it went. I've never constructed any track before and it was really easy to complete. To my eye it looks great and I'll be keeping tabs on future releases (the crossover shown on here has already caught my attention). A double slip would definitely be snapped up! 2 3 1 1 1 Link to post Share on other sites More sharing options...
Tankstage Posted September 23, 2021 Share Posted September 23, 2021 (edited) Snap for the double slip... My layout is waiting for 2 for me to start laying the main tracks ! Already bought 22 points... Edited September 23, 2021 by Tankstage Typo Link to post Share on other sites More sharing options...
RMweb Gold martin_wynne Posted October 5, 2021 RMweb Gold Share Posted October 5, 2021 @Wayne Kinney Hi Wayne, I believe you are working on pointwork for 3mm scale. You may find my post of interest: https://www.rmweb.co.uk/community/index.php?/topic/167289-choosing-which-switch-and-crossing-to-use/&do=findComment&comment=4596540 cheers, Martin. 1 Link to post Share on other sites More sharing options...
Wayne Kinney Posted October 5, 2021 Share Posted October 5, 2021 Thanks Martin, Wim requested that I design to 14.2mm exactly, using your FM-OLD settings. 1 Link to post Share on other sites More sharing options...
RMweb Gold martin_wynne Posted October 5, 2021 RMweb Gold Share Posted October 5, 2021 27 minutes ago, Wayne Kinney said: Wim requested that I design to 14.2mm exactly, using your FM-OLD settings. Hi Wayne, That seems sensible. I suspect that many 3mm modellers do the same. It's a bit strange of course for the 3mm Society to have 6 track standards, and specify none of them for its products. Martin. 1 1 1 Link to post Share on other sites More sharing options...
Popular Post Wayne Kinney Posted October 6, 2021 Popular Post Share Posted October 6, 2021 (edited) Hi Guys, Firstly I apologise for this long post, but I have been having a bit of an issue. It’s to do with the castings I use for the common & 'K' crossings. I received a large batch of 1in7 common castings and also new castings for the K crossings, both for diamonds and for slips. However, I am unfortunately pushing the lost wax casting technique to its limits here as the K crossings are much longer than the usual common crossing, so shrinkage and warpage is becoming an issue to the point where they are not really useable! It’s also apparent on the common crossing castings, they are slightly warped I’m just not happy with them. Also, the caster is getting close to retirement meaning future supply is going to be an issue. This has lead me to have a bit of a rethink. The use and reliance on castings for the kits has been bothering me for a good while, to be honest, for a few reasons: A) Having to rely on the casters timescales and as he is close to retirement, future availability is questionable. There are not many casters around that cast in Nickel Silver for the right price. B) The look/finish of the castings don’t fully match the code 75 rail and also changes from batch to batch. If I have to change to another caster/supplier then the material will change and maybe be a worse match. C) Getting the castings to match the tops of the rail height is a challenge, and can cause a bump on wheel sets D) Time consuming designing the CAD models for the wax masters. And then also having to make all the rubber moulds, time that could be better spend on developing new kit formations. E) It’s very time consuming for me to inject all the waxes, basically one at a time. Again, time better spend on other things. F) Time consuming having to cut each casting off the sprue and cleanup. Most castings have 3 sprues attached, the longer K crossing has 7! Time again. G) Cost, especially if I have to change supplier, making it unusable. All of the above reasons have lead me to wanting an “all rail” design, without using castings. After these EM gauge K crossing castings arrived and I can see they are going to cause me headaches, it’s really pushed me to look into changing to an “all rail” design. From the modellers point of view, these are the pros and cons of an all rail design: Pros: Better Looking all rail No need for blackening and polishing a casting Smoother Running (really nice!) More prototypical rail joint locations Better for curving the kit Cheaper Price Shorter development time for producing new kits Cons: Little extra Soldering Little extra cutting of rail Over the last few days, I’ve designed an “all rail” version of the K crossings and common crossings in EM Gauge (see pictures below) and they look great and run like butter – SO SMOOTH! The ‘V’s for the common crossing where milled on my CNC machine, and would be supplied pre machined like the switch blades are. I’ve designed special chairs that hold the point of the V’s down very firmly. The biggest challenge in designing it is that, once you bend pieces of rail (for example, to form the knuckle of the wing rails) you can’t then slide that bent piece of rail through the chairs on the base! Or worse, imagine forming the outside rail of a diamond crossing, a long piece of rail with a bend in the middle. Then imagine trying to insert that bent piece of rail though the chairs on the diamond base! It doesn’t work as it breaks the chairs. So instead, I have gone with the approach/solution of splitting it into 2 pieces of rail, that meet where the bend/knuckle is. This is what I’ve done in my tests and it seems to work out great. It will require a little more soldering of electrical feeds on the modellers part, though. I understand that the knuckle should theoretically have a slight radius, but this really does run incredibly smooth and I think it looks better than the cast version with gaps either side of it! So this is where I am as of last night. I would really need to move to using all rail and not have to rely on castings and all the work involved. A little more effort to build the kit, but they do look and function much better! I would need to change the instructions, I think this time having them online instead of printed, in a step by step form with each step accompanied a really small YouTube video. I am also going to be changing the design of the tie bar and how the switch blades are attached. Unfortunately, it’s taking up far too much time for me soldering the plates/pins onto each switch blade. Instead, I am going to change to a simpler design inspired by Normal Solomon, where 2x 0.4mm thick headed ‘pins’ are supplied with the tie bar, the builder inserts them so that the head of the pins are on the bottom, and the pins then bent over 90 degrees on the top of the tie bar. They are then cut off leaving about 2 – 3mm of the pin on top of the tie bar. The builder then solders the switch blades to the pin ‘in situ’. This is actually how the first kit was provided to Patrick on the first page of this thread! I realise the above changes will add a few extra steps in the build, but I truly believe the better cosmetic look and running outweigh this. I've not made the change yet so kits are still being provided with the castings, but I will announce when the change is made. Edited May 3, 2022 by Wayne Kinney 13 2 1 3 1 11 Link to post Share on other sites More sharing options...
RMweb Gold Harlequin Posted October 6, 2021 RMweb Gold Share Posted October 6, 2021 I thought the cast crossings were one of the cleverest parts of your designs, providing all the most complex interactions between rails, where tolerances are most important, in a ready made piece. 1 1 Link to post Share on other sites More sharing options...
Wayne Kinney Posted October 6, 2021 Share Posted October 6, 2021 (edited) 17 minutes ago, Harlequin said: I thought the cast crossings were one of the cleverest parts of your designs, providing all the most complex interactions between rails, where tolerances are most important, in a ready made piece. True, however it's running better and smoother without the casting Edited October 6, 2021 by Wayne Kinney 2 Link to post Share on other sites More sharing options...
KeithHC Posted October 6, 2021 Share Posted October 6, 2021 Bring them on Wayne they will look fantastic. I have just got to learn to solder properly…….. Keith 1 Link to post Share on other sites More sharing options...
Stanley Melrose Posted October 6, 2021 Share Posted October 6, 2021 Will this change make P4 versions more likely - even probable? I hope so! 1 Link to post Share on other sites More sharing options...
Wayne Kinney Posted October 6, 2021 Share Posted October 6, 2021 9 minutes ago, Stanley Melrose said: Will this change make P4 versions more likely - even probable? I hope so! It does make it more possible, I can hold tighter tolerances, this way. 1 1 Link to post Share on other sites More sharing options...
Chuffer Davies Posted October 6, 2021 Share Posted October 6, 2021 Hi Wayne, What a shame.... I would have to agree that the castings are both a strength and a weakness in your product. The vertical alignment between the code 75 rail and the top of the frog's casting were slightly out on my three test EM points but it would have been a simple matter to run a file over the top to remove any step had it bothered me sufficiently. If, however, shrinkage and reliability of supply are going to become an issue then you are going to have to change your approach. Who knows, in years to come metal 3D printing of frogs and K crossings might become practical but that time is not yet I understand. Would it be possible to print the sleeper base of the diamond as two separate ends with some kind of clip in the middle to lock them together when pushed home? By starting at the middle of the diamond and sliding continuous side and check rails into both bases at the same time I would have thought it would still all come together neatly? Just an idea! Pre-machined rails definitely remove much of the complexity of building trackwork so these kits will still be enormously beneficial. Shame about the tie bars though, I particularly liked your current solution. The new approach is one I've seen used with varying degrees of success in the past so may become the most challenging element of the revised design for the novice builder. Keep up the great work..... Frank 1 1 Link to post Share on other sites More sharing options...
hayfield Posted October 6, 2021 Share Posted October 6, 2021 One of the main resistances may be peoples reluctance/fear of soldering. Clear instructions of what materials and tools to use plus an idiots guild (video) is a must For me a decent quality solder and flux is a must, also advice on which Iron to use The up side is that they will be able to solder dropper wires, and perhaps might then venture into kit building of the odd wagon or coach I think getting over the fear aspect is the biggest hurdle, pre-machined parts will take away the difficult processes 1 2 1 3 Link to post Share on other sites More sharing options...
Zunnan Posted October 6, 2021 Share Posted October 6, 2021 I must admit, the all rail does look pretty snazzy. But like the N gauge range, the big draw for me is the simplicity of construction thanks in part to the use of castings. Having said that, I'm only trying to avoid copperclad construction and the time sink making track from C&L components can be. A bit of soldering isn't the end of the world by any means given the accuracy of the alignment is governed by the sleeper base, and to be honest, transitioning from rail to casting and back to rail over longer distance inherently brings in its own alignment issues so for the K an all rail approach is probably favourable. Keeping the cast frog I think would be a good call however. In the spirit of the range though, would 3D printing using nickel alloys be a feasible approach for future supplies? A bit early in the metal printing process still, but who knows what the future may bring. 1 1 Link to post Share on other sites More sharing options...
dpgibbons Posted October 6, 2021 Share Posted October 6, 2021 10 hours ago, Wayne Kinney said: Instead, I am going to change to a simpler design inspired by Normal Solomon, where 2x 0.4mm thick headed ‘pins’ are supplied with the tie bar, the builder inserts them so that the head of the pins are on the bottom, and the pins then bent over 90 degrees on the top of the tie bar. They are then cut off leaving about 2 – 3mm of the pin on top of the tie bar. The builder then solders the switch blades to the pin ‘in situ’. I have built 7mm turnouts that use this method. I found it difficult to bend the pins flush with the tiebar, awkward to solder and tricky to ensure clearances. The pin into PCB method used in Finetrax N is more involved but gives consistent results and allows the tiebar to be mounted and tested before soldering the pins. 1 Link to post Share on other sites More sharing options...
BWsTrains Posted October 7, 2021 Share Posted October 7, 2021 Hi Wayne, Where does this leave existing products like the B7 OO and soon to be availables like the B6 etc.? Will they be facing a change in Frog as well given the common denominator here is the Caster and casting. For my needs I'll be all for the current product form for simple turnouts. Colin Link to post Share on other sites More sharing options...
RMweb Gold martin_wynne Posted October 7, 2021 RMweb Gold Share Posted October 7, 2021 (edited) On 06/10/2021 at 14:27, Wayne Kinney said: am also going to be changing the design of the tie bar and how the switch blades are attached. Unfortunately, it’s taking up far too much time for me soldering the plates/pins onto each switch blade. Instead, I am going to change to a simpler design inspired by Normal Solomon, where 2x 0.4mm thick headed ‘pins’ are supplied with the tie bar, the builder inserts them so that the head of the pins are on the bottom, and the pins then bent over 90 degrees on the top of the tie bar. They are then cut off leaving about 2 – 3mm of the pin on top of the tie bar. The builder then solders the switch blades to the pin ‘in situ’ @Wayne Kinney Hi Wayne, May I offer the design of tie-bar which I supplied with my turnout kits back in the 1970s ? The great advantage of the little groove is that it locates directly onto the rail foot, so can be assembled dry before soldering, with some packing between the blade and stock rail. Easy to solder* because the solder flashes into the groove. Easy to assemble and ensures the correct designed switch opening. The pin is turned from 3mm bar. You should be able to find a local engineering firm with a small traditional auto or CNC lathe who can turn a few thousand for you in an odd moment. The exact profile of the groove isn't too critical, from a form tool -- give them a sample of the rail. Google "repetition turned parts". * make sure they are well degreased from the machining so that folks don't have any trouble soldering to them. cheers, Martin. Edited February 29 by martin_wynne lost image replaced 7 3 1 3 Link to post Share on other sites More sharing options...
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