mike knowles Posted January 26, 2011 Share Posted January 26, 2011 Hi Mike My Buddy has used Merg controllers and mini servos on Moor street, Once he uprated the capacitors they have had no problems to report. Cheers Jim Having just fitted the MERG controllers and servos on our club layout Battersby North End I'm curious to know of the problems you had with the capacitors and what the replacements were. (Up to now ours have worked fine). Link to post Share on other sites More sharing options...
the penguin of doom Posted January 26, 2011 Share Posted January 26, 2011 The lower quadrant arms on the Hessle Haven signal bridge have proved quite problematical, though I think the problems have now been solved and the arms and their operating mechanisms seem to work well. Having solved the problems on the full size arms with reasonably tall dolls, now time to tackle those shorter dolls with smaller arms on the Scarborough bridge. So, in at the deep end with the smallest doll on the Scarborough signal bridge. The photo below shows this doll mid way through the detailing phase, with the balance lever and operating rod fitted and working. The finial, atop this doll, is 15 mm high; the operating rod is .3 mm wire, which gives some idea of the size of this doll and its arm. Now another seven of these small dolls and arms to do, though they are all larger than this one. As on the larger dolls with full size arms, the travel of the arm and its horizontal danger position are governed by the stops on the lever casting, visible above and below the balance lever; this as per the NER prototype. This avoids having to fit arm stops to achieve that same governing of the travel. The photo is approximately two and a half times the size of the model. Cheers Mike Hi Mike. Just browsing around the site and double checking these small dolls. They really do look nice and just like the prototype. Given that they're about half the size of the others, double well done to you. :clapping_mini: Cheers. Sean. Link to post Share on other sites More sharing options...
Guest jim s-w Posted January 26, 2011 Share Posted January 26, 2011 Hi Mike I'll ask for you. The problem was a very loud bang followed by lots of blue smoke. It happened on more than one occasion. I am no electronical person so I will ask for a better description. Cheers Jim Link to post Share on other sites More sharing options...
mikemeg Posted January 27, 2011 Author Share Posted January 27, 2011 Hi Mike. Just browsing around the site and double checking these small dolls. They really do look nice and just like the prototype. Given that they're about half the size of the others, double well done to you. :clapping_mini: Cheers. Sean. Thanks Sean. Tell you what, mate, when the old motivation flags a bit and I realise that I have to do everything on this model ten, eleven or twelve times then comments like the one above are a hell of a fillip and really do help me to just carry on until it's all done. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted January 27, 2011 Author Share Posted January 27, 2011 Someone asked, via a PM, to see how the balance levers and operating rods were organised on these ex-NER slotted post lower quadrant signals, so at the risk of some repetition, here goes. The balance levers use the standard MSE etch but with the actual weight augmented in thickness by adding a .010" plasticard disc superglued to each side of the etch and then finished off to the circular profile of the etched weight. This takes only a minute or two for each lever. The actual balance lever casting is fabricated using the standard MSE balance lever plate, with a square 'U' shaped piece of .6mm x .010" brass strip soldered to the back of the plate and then thinned - the photo shows how this is arranged. Each lever has a tiny washer soldered to each side at the pivot point, this to increase the bearing area and to provide the spacing. Where multiple levers are installed on a single spindle, as with this doll, I normally aim to achieve a 1.0 mm spacing between adjacent levers to allow for the loops in the wire. Even then, these loops must be made pretty tight to avoid fouling the adjacent lever. The spindle is 0.5 mm brass wire which has two small washers soldered to the free end to retain the levers. The spindle is then soldered into the base plate, taking care not to solder up the levers themselves. Sounds complex though it isn't but it does require a little care. The operating rods, which are made from 0.3 mm brass wire, are shaped prior to fitting. The lower end is looped through the balance lever after softening the end of the wire in a flame. The other end of the operating rod, which joins the arm, is slotted into a 3.5 mm piece of 1/32 " brass tube, the other end of which has another tiny piece of 0.3 mm wire which is sweated into the tube and then looped through the holes on the lug on the arm, allowing this tiny tube to pivot on the operating lug on the arm. The operating rod is then glued into this tiny tube using slow setting superglue, with the lever at its lowest position and the arm is then adjusted, while the glue is still pliable, to sit horizontally with the lever at this lower position. Just by way of a datum point the doll, in the left hand photo, is 2.5 mm wide at the point where the balance lever assembly is attached, which indicates the size of this assembly. So that's about it and that's how these arms are driven. Cheers Mike Link to post Share on other sites More sharing options...
Guest jim s-w Posted January 27, 2011 Share Posted January 27, 2011 Having just fitted the MERG controllers and servos on our club layout Battersby North End I'm curious to know of the problems you had with the capacitors and what the replacements were. (Up to now ours have worked fine). Hi Mike "The problem component is capacitor C1 which I change from a 16V to a 25V rated part to allow me to use a standard 16V AC power supply - there don't seem to be any consequences of doing this." I assume that means more to you than it does to me. HTH Jim Link to post Share on other sites More sharing options...
mike knowles Posted January 27, 2011 Share Posted January 27, 2011 Hi Mike "The problem component is capacitor C1 which I change from a 16V to a 25V rated part to allow me to use a standard 16V AC power supply - there don't seem to be any consequences of doing this." I assume that means more to you than it does to me. HTH Jim Cheers Jim. Electronics totally baffle me too (though I must say the MERG kits are dead easy to build and they are very helpful if you have a problem) I'm actually using a 9v DC supply and as I said earlier all seems to be OK so far. Link to post Share on other sites More sharing options...
RMweb Gold Steve Hewitt Posted January 27, 2011 RMweb Gold Share Posted January 27, 2011 How am I going to make it work? Don't know, yet; I would love to use memory wire but I'm not sure about the reliability of this stuff across a temperature spectrum of, say, 10 C to 30 C. I think a chat with your Moor Street buddy might be helpful - PM me with details if you would. Hi Mike, Such a great signal deserves the best in motive power. I'd strongly recommend using servos. With an appropriate controller, you can get a really good movement to each arm. The problem with memory wire if used conventionally, i.e. heated to contract to pull the signal to Clear, cool to return to Danger, is the speed of movement is opposite to what you expect. The signal will move quite quickly to Clear, but return to Danger much more slowly. The implementations of memory wire which I have seen are also quite space hungry. You can get a lot of servos in a small space. Here are twelve driving the arms of a gantry from Liverpool Lime street: This picture shows the signal on its testing/transport frame. Steve. Link to post Share on other sites More sharing options...
mikemeg Posted January 27, 2011 Author Share Posted January 27, 2011 Steve, Many thanks for the kind comments and for the info. I think I am coming to the view that servos are the best - probably the only - way of driving this model. I do have some detail questions about which servos, their cost and the way in which they are used; I'll PM you for some more info or perhaps this info might be generally useful to the thread and to other readers/contributors, so which servos, what servo control mechanism, their cost, etc. if you would be prepared to post a more detailed description Once again, many thanks. Cheers Mike Link to post Share on other sites More sharing options...
wychcan Posted January 28, 2011 Share Posted January 28, 2011 Mike, I, like you, would be grateful to Steve if he would share his ideas on the use of servo's with signals. As always, Mike, a great thread that you share with us all on your signals. thanks, Nigel Link to post Share on other sites More sharing options...
RMweb Premium PaulCheffus Posted January 28, 2011 RMweb Premium Share Posted January 28, 2011 Cheers Jim. Electronics totally baffle me too (though I must say the MERG kits are dead easy to build and they are very helpful if you have a problem) I'm actually using a 9v DC supply and as I said earlier all seems to be OK so far. Hi In simple terms you should use Capacitors with a higher voltage rating than the input. So with the original you were feeding 16v into a capacitor rated at 16v, however, the supply would have been higher than 16v even though it is marked as 16v hence the capacitor smoking. The original design suggests a supply of 12v. Cheers Paul Link to post Share on other sites More sharing options...
mikemeg Posted January 28, 2011 Author Share Posted January 28, 2011 There are numerous repetitive and tedious jobs in making these things but it doesn't get very much more repetitive and tedious than adding the diagonal bracing across the underside of the lattice girder. The small squares of plasticard (3.5 mm x 3.5 mm x .015"), glued between the two lattice girders on the left of the photo are to support and fix the bottoms of the dolls when they are fitted into the lattice. So I think it's time for a little r&r; a couple of days by the seaside, out of season. Scarborough sounds good at this time of year!! Shame there are no signal bridges to photograph - ah, if only. Cheers Mike Link to post Share on other sites More sharing options...
RMweb Gold Steve Hewitt Posted January 30, 2011 RMweb Gold Share Posted January 30, 2011 Steve, ..... I do have some detail questions about which servos, their cost and the way in which they are used; I'll PM you for some more info or perhaps this info might be generally useful to the thread and to other readers/contributors, so which servos, what servo control mechanism, their cost, etc. if you would be prepared to post a more detailed description ..... Cheers Mike Mike, Rather than clutter up this delightful thread with stuff about servos which might also be of interest to others who aren't follwing your work, I'll start another topic from scratch. I'll put a link on this thread when I've done it. (If I can) Steve. Link to post Share on other sites More sharing options...
Gallows Close Posted January 30, 2011 Share Posted January 30, 2011 Mike, Rather than clutter up this delightful thread with stuff about servos which might also be of interest to others who aren't follwing your work, I'll start another topic from scratch. I'll put a link on this thread when I've done it. (If I can) Steve. Hi Steve, I for one would be very interested to see how you have made models on the scale of Mike's work. Please tell us the thread name if you cant't post a link directly. Mike, I do hope you enjoyed a January stroll along South Bay Beach. Cheers, Chris. Link to post Share on other sites More sharing options...
RMweb Gold Steve Hewitt Posted January 30, 2011 RMweb Gold Share Posted January 30, 2011 Mike, Rather than clutter up this delightful thread with stuff about servos which might also be of interest to others who aren't follwing your work, I'll start another topic from scratch. I'll put a link on this thread when I've done it. (If I can) Steve. I hope this is the link! http://www.rmweb.co.uk/community/index.php/topic/30110-servo-motors-servo-controllers/ Steve. Link to post Share on other sites More sharing options...
mikemeg Posted January 31, 2011 Author Share Posted January 31, 2011 Mike, I do hope you enjoyed a January stroll along South Bay Beach. Cheers, Chris. A crisp yet still day, cold but not raw with a sea so flat calm you could see the reflection of the sky in it, perfectly. A couple of fishing boats coming into the harbour around 4.30 just before darkness fell completely and a myriad lights from the shore all reflected in the steel grey sea. These seaside resorts, out of season, are just magical places, especially if, as with Scarborough, they no longer close down during the winter. So everything is there except the throngs of day trippers. So yes indeed, I did enjoy a stroll along the South Bay Beach; who wouldn't? Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted February 1, 2011 Author Share Posted February 1, 2011 All of the diagonal bracing on the underside of the lattice is now added. I didn't count how many individual pieces were involved but just from the simple maths, well over a hundred. I always feel a pang of regret when I prime the lattice with the disappearance of all of that shiny brass and nickel silver; replaced by a dull uniform grey. But this makes an enormous difference to the job of painting the lattice. The decking has had a first coat of a mixture of stone and natural wood and I may leave it as it is. The first coat isn't entirely uniform but does give that appearance of well worn and weathered wood. The last of the eleven dolls has been fabricated and just needs glueing together with its lower quadrant arm 'trapped' in the slot. Dolls 9 and 10 are made and now need the arm bearings and arms adding. So now it's just the adding of all of the balance levers, operating rods and wires, lamps and back blinders before I then start on the linkages across the decking from the track formation. After that then ladders, steps on the shortest dolls and finally the handrail with its seventy odd stanchions glued into the tiny stanchion castings. So, gradually, this model is moving towards completion. One thing I have striven very hard, to achieve, is absolute straightness and squareness on the lattice structure. I've said it before but these things were extraordinarily elegant structures and never more so than with their arrays of lower quadrant arms and slotted posts. Hopefully the model begins to convey something of that design elegance. Many thanks to Steve for his thread on use of servos which will certainly be of great value to me and, hopefully, to others. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted February 2, 2011 Author Share Posted February 2, 2011 I'm now only one doll and one arm away from having all eleven dolls and twelve arms done. That's a good excuse for a celebratory glass (more likely a bottle) of red wine. I'm on the home stretch of this one, though it could be a fairly long home stretch, there's still quite a bit to do. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted February 3, 2011 Author Share Posted February 3, 2011 Hi Mike Is that it? What I mean is, is that all of the arms you need or are there more? Cheers Jim This is the full configuration of dolls and arms, with all now made. The smallest doll; the one rightmost on the photo, still has to have its finial added. Then all of the dolls will have any missing details completed - post caps, lamp brackets, etc, before I work sequentially through them adding balance levers and operating wires or rods. On the larger of the two bridges, shown below, the arms on dolls 1 & 2, dolls 4 & 5 and dolls 9,10 & 11 should all sit at the same levels, though different levels across each grouping. Any slight errors are corrected by adding slivers of .010" or .020" plasticard to the bottoms of the dolls. The digital camera is invaluable in achieving these levels. I've only just realised that I will need to assemble twenty four of those tiny pulley wheels. Checking on how many I have left there are three, so an order's been placed on the supplier for more. So much for the planning on this one; stock control dept. have failed once again. I've deliberately left the Hessle Haven bridge, for a couple of weeks, to check that the dolls on this bridge stay absolutely straight, having had a problem with one of the dolls on an earlier model going badly askew. I think this was probably a function of assembling that doll before the poly adhesive on the two halves had completely dried and 'cured'. So while I wait for more supplies, time to complete the Hessle Haven bridge and, perhaps, start on the jigs for the next one - the now famous and lately departed (last of the line) Falsgrave signal bridge. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted February 4, 2011 Author Share Posted February 4, 2011 Just out of interest and by way of comparison, here are the first two 4mm model signals I ever built, done a couple of years ago. These, like most of the models featured on the last two threads, are for Hessle Haven. These use the same techniques, though some have been modified and developed, as the models covered in this thread. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted February 4, 2011 Author Share Posted February 4, 2011 And this is still one of my favourite photographs and encapsulates all that I strive to achieve. The sunlight on this is real, no-one could produce light like that artificially. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted February 9, 2011 Author Share Posted February 9, 2011 While I finish the Hessle Haven bridge, work is still progressing on the Scarborough bridge. Having eleven dolls and twelve arms - 6 lower quadrant, 6 upper quadrant - means that balance levers, spectacle plates, lamps, etc. all have to be done in batches of six. Normally I do a couple extra on every batch which will lighten the load on the next model. So I already have half of the arms which I shall need for the Falsgrave bridge and have some of the balance lever assemblies also. So now just going through doll by doll adding the detailing prior to linking them all up to the operating wires. Cheers Mike Link to post Share on other sites More sharing options...
davidw Posted February 9, 2011 Share Posted February 9, 2011 Excellent bit of maodelling! Link to post Share on other sites More sharing options...
the penguin of doom Posted February 9, 2011 Share Posted February 9, 2011 Awesome Mike. Just awesome. Hey, I've finished with my coffee stained Modellers Back Track with the picture of Falsgrave in the 1930's. If you want it, PM me with your address. Cheers, Sean. Link to post Share on other sites More sharing options...
mikemeg Posted February 10, 2011 Author Share Posted February 10, 2011 Awesome Mike. Just awesome. Hey, I've finished with my coffee stained Modellers Back Track with the picture of Falsgrave in the 1930's. If you want it, PM me with your address. Cheers, Sean. Thanks to Sean and to David above. Despite the fact that I am pretty determined in doing this stuff, comments like yours above really do help to sustain the motivation. So many thanks to you and to others who have been very constructive throughout the thread. Certainly helps to make all of this worthwhile. Cheers Mike Link to post Share on other sites More sharing options...
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