RMweb Gold martin_wynne Posted July 9, 2016 RMweb Gold Share Posted July 9, 2016 Perhaps Martin could confirm the gap between the switch rails for 4SF Hi John, Mike, You mean at the tip? The prototype opening is 4.1/4", i.e. the amount by which one blade tip is away from the stock rail when the other one is closed against it. That scales to 1.42mm in 4mm/ft scale. However you need rather more than that in 4-SF and EM to ensure that you have the minimum flangeway clearance of 1mm all along behind the open blade. I suggest 1.75mm opening for 4-SF and EM. That is conveniently the thickness of a 20p coin which can be used to set the open gap. The distance across the two tips obviously depends on the track gauge. Subtract 1.75mm from the track gauge you are using to find the distance across the two tips. Subtract from that the thickness of your two blade tips to find the distance between them. regards, Martin. Link to comment Share on other sites More sharing options...
Grovenor Posted July 9, 2016 Share Posted July 9, 2016 Have you found any tiebars that look good that would work with 4-sf? Or is the copperclad strip the best way? Ambis do tie bars, generally similar to Masokits (actually the other way round, the Ambis ones came first). The Ambis ones can be assembled for any desired track gauge. Regards Link to comment Share on other sites More sharing options...
hayfield Posted July 9, 2016 Author Share Posted July 9, 2016 Thanks, I will look into that. Btw are there any check chairs that would work fine with 4-sf? (just thinking the EM guys use a 1mm gap so what they use should work right?) Or is it a case of mashing up 2 normal chairs? Mike Re check chairs, you need a 1 mm gap (though like EM & P4 you should set the check rail from the vee) but there are no 1 mm check chairs The dodge for EM and 00SF is on a 4 sleeper check rail I cut through the .8 mm chairs to take one outer half chair off. 2 middle chairs are threaded on to the check rail and the 2 outer chairs are threaded on to the stock rail. For a five chair check rail the 2 outer and one middle chair are threaded on to the check rail and 2 middle chairs on to the stock rail. On the right is a check rail with the 3 chairs threaded on, the right hand check rail has the half chairs cut off, extreme right are the check chair halves waiting to be stuck in place Just stick the check rail in place (using either a gauge or digital caliper) which is more or less next to the stock rail anyway The half chairs are just glued in place in the resulting gaps For 00 gauge a little filler may be needed to bridge the gap left between the check chair and rail 1 Link to comment Share on other sites More sharing options...
hayfield Posted July 9, 2016 Author Share Posted July 9, 2016 (edited) Hi John, Mike, You mean at the tip? The prototype opening is 4.1/4", i.e. the amount by which one blade tip is away from the stock rail when the other one is closed against it. That scales to 1.42mm in 4mm/ft scale. However you need rather more than that in 4-SF and EM to ensure that you have the minimum flangeway clearance of 1mm all along behind the open blade. I suggest 1.75mm opening for 4-SF and EM. That is conveniently the thickness of a 20p coin which can be used to set the open gap. The distance across the two tips obviously depends on the track gauge. Subtract 1.75mm from the track gauge you are using to find the distance across the two tips. Subtract from that the thickness of your two blade tips to find the distance between them. regards, Martin. Martin It was the gap between the tips of the 2 points of the switch rails, which you have confirmed to be 1.75 mm plus the width of both rails subtracted from the gauge (this will be different to both tiebars as the forward one is on thicker rail width (owing to the rail taper) Thank you Edited July 9, 2016 by hayfield Link to comment Share on other sites More sharing options...
RMweb Gold martin_wynne Posted July 9, 2016 RMweb Gold Share Posted July 9, 2016 It was the gap between the tips of the 2 points of the switch rails, which you have confirmed to be 1.75 mm plus the width of both rails subtracted from the gauge (this will be different to both tiebars as the forward one is on thicker rail width (owing to the rail taper) Hi John, The 1.75mm is the opening at the tip (at the first stretcher bar). If you have a second stretcher bar the opening there will be less than 1.75mm because of the curve of the rail. regards, Martin. Link to comment Share on other sites More sharing options...
MikeH_83 Posted July 9, 2016 Share Posted July 9, 2016 Thanks John, Right time to have a clean up and then onto templot to design the layout. Cheers Link to comment Share on other sites More sharing options...
Stephen Freeman Posted July 11, 2016 Share Posted July 11, 2016 (edited) Ambis do tie bars, generally similar to Masokits (actually the other way round, the Ambis ones came first). The Ambis ones can be assembled for any desired track gauge. Regards Yes but both are intended to represent the more modern type of stretcher bar rather than the earlier round type. The Masokits version is perhaps slightly more robust as it has some etched brass re-inforcement but there again it depends on the thickness of the pcb you use with the Ambis version. With the Masokits you have to stick with the thickness of the pcb supplied, whereas with the Ambis ones you can be more flexible but at the cost of appearance. For the rod type, he does do some rod ends but I am still investigating how they work. From an entirely different source (not me), my spies tell me that there may be some exciting news for GWR track enthusiasts in the pipeline. Edited July 11, 2016 by Stephen Freeman Link to comment Share on other sites More sharing options...
hayfield Posted July 12, 2016 Author Share Posted July 12, 2016 For those who do not bother looking at any posts with P4 in them this is what has been on the workbench Took as long to build the whole thing as fitting one stock rail on the Massokits turnout, not quite finished as I am waiting for some cast slide chairs so I can make the tiebar out of the 3rd timber I keep banging on about the Exactoscale special chairs, a good shot of their detail Next up a copperclad of an old SECR turnout, then for a change a flatbottom (code 82) chaired turnout 3 Link to comment Share on other sites More sharing options...
hayfield Posted July 16, 2016 Author Share Posted July 16, 2016 Quite a few bits on the go at the moment The bonding wires have been added to the P4 turnout which is now finished Built another turnout representing a Fox Henderson design for the 1840's Whilst I wait for a proper modelling room I have decided to build a small Cameo of the engine shed area of Bodmin General station. initially I am building the turnout on the mainline to the engine shed plus to turnout which has two trap points at the entrance of the shed. Once this is built then I will work on the shed building. Initially is was going to be built to 00SF standards on plastic timbers, but after seeing Mikkel's latest model I decided to switch to ply timbers for both the turnouts and plain track. In the end and as I have plenty of EM Gauge society plain ply sleepers I thought I might as well build it to EM standards. Well a start has been made and all the timbers are cut. In the meantime I have a code 82 flatbottom turnout to build with ST base plates on plastic sleepers 3 Link to comment Share on other sites More sharing options...
hayfield Posted July 18, 2016 Author Share Posted July 18, 2016 (edited) Next up on the bench is a Code 82 flatbottom turnout, the build sequence is much the same but with a few tweaks. The turnout has a 16.2 mm gauge (00SF) through the crossing opening up to 16.5 at the entrance and exits My EM gauge society Vee filing jigs only work on one rail due to the width of the flatbottom rail, also for sharp bends you will need to cut nicks into the bottom of the rail for sharp bends, there are two notches cut into the rail (the rear notch on the inside of the bend is not very clear in the photo). The notch on the inside is the most important The common crossing is built much the same The chairs opposite the common crossing are stuck using 00SF gauges, the heal end is set with an 00 gauge and the foot end stuck in place by eye. The rest of the chairs will be set in place with solvent once the initial ones have set hard Edited July 21, 2016 by hayfield 3 Link to comment Share on other sites More sharing options...
Stephen Freeman Posted July 21, 2016 Share Posted July 21, 2016 Hi, I know you need a nick in the foot of the rail for sharpish bends, but I think you might be better doing it on the inside of where you want the bend. Then when you bend it the gap created by the nick closes up. You can then solder it up for strength and appearance if you wish, though of course it might still just be visible. I've always found it works better that way anyhow. Link to comment Share on other sites More sharing options...
hayfield Posted July 21, 2016 Author Share Posted July 21, 2016 (edited) Stephen for the tip, I notched both sides, the thought process was to reduce any excessive curving at the bend, I know it is not an acute angle and has a little curving at the bend. On this turnout the chair hides the bend on the outside, the inside of the throat is not noticeable. Again thanks for the tip as some plans do have the bend away from the timber and it would be more noticeable Edit I have just re-looked at the photo's, the notch on the further side is not visable Edited July 21, 2016 by hayfield Link to comment Share on other sites More sharing options...
Mrkirtley800 Posted July 21, 2016 Share Posted July 21, 2016 I agree with Stephen, I notch bullhead rail in the same way, helps to produce a cleaner bend. Derek Link to comment Share on other sites More sharing options...
hayfield Posted July 21, 2016 Author Share Posted July 21, 2016 The turnout is coming along, The ST base plates seem a bit easier to fit than normal chairs. Slide chairs will be added next and off to make the first switch rail Link to comment Share on other sites More sharing options...
hayfield Posted July 22, 2016 Author Share Posted July 22, 2016 The flatbottom turnout is now finished Pity the slide chairs to match were never made, but once painted should blend in well Been having fun with Templot, had a plan to scan in but as I only have an A4 printer/scanner I had to knit together 3 scans. I worked out what to do without really knowing what exactly I was doing, in the end I got there and after printing off the plan on tracing paper. Thankfully the overall plan is was nearly a perfect match allowing the complex within the drawing to be designed. The drawing was a guide and the plan is well within the tolerances given 2 Link to comment Share on other sites More sharing options...
hayfield Posted July 25, 2016 Author Share Posted July 25, 2016 (edited) The latest project, a junction with plenty of diamonds and a 3 way, the timbering is slightly out, but I find it much easier doing the final adjustments on the board rather than on the screen Simply start at one end for the turnout then with the long timbers fit the ones that must not move (tip of the Vees and the obtuse (K) crossing) first. At this stage the longest timbers on the Exactoscale sprue are not long enough, so will need extending, but I carry on laying them out first and extend them later As for the long timbers, I know the longest ones were often spliced together away from chairs etc in plain sight, my view is that in model form the joints do not scale down visually so I hide the join under a chair I find it helps to start adding adjoining turnouts and crossings to ensure I am happy with the flow, then I start making the timbers the correct length. I like to make the join under a chair. This gives the join added strength and hides it, also I cut the adjoining timber at the other end again for strength (the joints do not run in a line next to each other) I am also looking at the spacing of the timbers and adjust accordingly Here you can clearly see I cut the timbers at opposite ends and where a chair will hide it Once the timbers are cut to size I fit the sleepers which fill any gaps between turnouts and crossings. The timbers are the Exactoscale ones and the sleepers the thick (to match the timbers) C&L ones. I will give the timbering the once over in the morning in day light Edited July 26, 2016 by hayfield 5 Link to comment Share on other sites More sharing options...
mightbe Posted July 26, 2016 Share Posted July 26, 2016 Out of curiosity, why not lay full-length timbers and create fake splices after laying? You'd have the strength from the outset and wouldn't be relying on the chairs. You also have the option of doing visible joins. Quentin Link to comment Share on other sites More sharing options...
hayfield Posted July 26, 2016 Author Share Posted July 26, 2016 Quintin My explanation was not clear enough and perhaps confused the process by stating what happens in the real world. The longest plastic timbers on the Exactoscale sprue were not long enough, so I had to add an extra length to each of them. Unlike on the prototype I will not splice the join between two rails so its visible as the join will be too prominent. The idea is to hide the join If you look at the second photo the right hand half of the long timbers have been extended, the right hand ones have not and are too short Looking at the third photo you can see the timbers have been cut to where a chair will be and have alternated the side of each timber where the cut has been made The last photo shows all timbers have been extended. Far easier to do than describe Link to comment Share on other sites More sharing options...
mightbe Posted July 26, 2016 Share Posted July 26, 2016 Ah, I missed the part where you'd said "Exactoscale sprues". I'd assumed you were using stained ply or similar. Mea culpa. Makes perfect sense now. Link to comment Share on other sites More sharing options...
hayfield Posted July 26, 2016 Author Share Posted July 26, 2016 Ah, I missed the part where you'd said "Exactoscale sprues". I'd assumed you were using stained ply or similar. Mea culpa. Makes perfect sense now. Quentin You missed nothing, I edited it in this morning after your post. There has been discussion after discussion about the longest lengths of timber and I guess that I have made many mistakes in my placements, and there might have been a series of shorter interlaced timbers. I also might have a slight issue with the 3 diamond crossing timbering at the centre as usually above 1-5 crossings there is a central timber so I will just have to check the angles, then slightly alter my build method if I cannot add the central timber Link to comment Share on other sites More sharing options...
hayfield Posted July 26, 2016 Author Share Posted July 26, 2016 (edited) I have decided to work from the centre of the complex outwards, 6 common crossings have been built today, that's half of what is required for the whole of the complex, glad I built a variable angle soldering jig as angles varied and all but one non standard angles Next I will have to prefabricate a few more parts before the centre part can be assembled. Once the centre two diamonds have been fitted the build should be a bit less demanding Edited July 26, 2016 by hayfield 2 Link to comment Share on other sites More sharing options...
hayfield Posted July 29, 2016 Author Share Posted July 29, 2016 A quick update on the progress of the formation build First I have replaced a few of the plastic timbers for wooden ones whilst I am building the obtuse (K) crossings (whilst soldering is going on), these will be replaced with the plastic ones once I have finished building the complex. The centre two common crossings have been fitted which will allow me to set the obtuse (K) crossings in the centre of the formation, this will be the datum point from which everything else will flow Looks a total mess but after fitting the next common crossing I wanted to test it. I built 2 short lengths of track 6" long with 5 sleepers, as you see these can fit in between the sleepers and used for testing A closer view, I always find it better to test with a loco rather than a wagon, as it will show up faults better The common crossing is starting to take shape, again a short length of rail used to test this stage, I may have a slight issue with the first right hand common crossing which may meed replacing as I may have made a slight error with the design or its just the fact of the slight differing curves these are on. Not an issue its just these had to be fitted prior to the obtuse crossings and will have to be adjusted after if necessary 3 Link to comment Share on other sites More sharing options...
hayfield Posted July 29, 2016 Author Share Posted July 29, 2016 (edited) A quick update Whilst not finished the first diamond crossing is coming on well and waiting for chairs to set before I can do some final tweaking. For something different I will build the small turnout on the bottom left of this photo next, before tackling the diamond crossing opposite it Note the lengths of test rail being used, simple but effective Work beacons Edited July 29, 2016 by hayfield 2 Link to comment Share on other sites More sharing options...
hayfield Posted July 30, 2016 Author Share Posted July 30, 2016 A quick update on the complex The central diamond has been adjusted tested and fully chaired except for where the wooden timbers are. I was only going to build the lower left hand turnout before I start the next diamond (above the one I have built) after making the smaller turnout, but as I need to make another common crossing I decided to start fitting the first stock rail of the larger turnout Tomorrows job is to finish the smaller turnout and do the diamond Sorry for the quality of the photos, I must upgrade my iPhone and learn to take photos 2 Link to comment Share on other sites More sharing options...
mightbe Posted August 1, 2016 Share Posted August 1, 2016 Hi John, I see you're using PCB in the middle of the formation, presumably .5 mm thick. Where can one buy that thickness? I checked Eileen's but they only had .25 mm Quentin Link to comment Share on other sites More sharing options...
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