Simond Posted September 7, 2016 Share Posted September 7, 2016 I can help with #3. A DCC turntable needs to be supplied continuously, or the sound stops & restarts unrealistically. And (guess when I realised) it cannot be supplied by the traditional "slip-ring" or split support rail, as the continuous supply means that when the table bridges the gap, the DCC shuts down. So, what I did was... Connect one rail of my t/t to the deck - mine is a Metalsmiths GW 65', and the deck is made from double-sided PCB - and from the deck to the central pivot axle. The other rail is connected to an wiper which runs on the support rail, which is continuous all the way round. You'll have to gap the PCB accordingly. Believe me, it would have been easier before I built it... To avoid the pivot bearing being damaged by sparks, there's a wiper, possibly not needed, but little effort for a little security. The wires from the support rail and wiper are connected to a DPDT relay set up as a reversing switch. The relay in my case is triggered by the Arduino that controls the stepper motor which drives the t/t, but it could just as easily be by a cam and microswitch. HTH Simon Link to post Share on other sites More sharing options...
south_tyne Posted September 7, 2016 Share Posted September 7, 2016 I prefer the third design, somehow it looks a little more natural to me eye. I think the idea of an industrial line feeding into the layout (as Middleton) is excellent and will offer more interest. I've always been fascinated by terminus stations that have multiple exits like this, alhough probably rare in reality that do offer great operational interest. It really helps with some stock in the layout in order to give some perspective... nothing heard full-size planning! David Link to post Share on other sites More sharing options...
MarcD Posted September 7, 2016 Share Posted September 7, 2016 The kick back line off the slip on "Scratchy Bottom" goes though a gate that opens and closes and runs off to an off screen industry. In this case a paper mill, the owner of the mill is Mr M R Royds trading as "Scratchy Bottom Paper Mills Ltd." The sidings are used for traffic exchange from the paper mill and the branch. This means I can operate without the use of the fiddle yards if I want. Last year we had 2 3ft boards as the supports fo cassettes this didn't work well and we are building 2 4ft boards to fit traversers to and the 2 spare boards are being used to extend one end. Marc Link to post Share on other sites More sharing options...
two tone green Posted September 7, 2016 Share Posted September 7, 2016 Feed the bridge off a frog juicer. Simple. Link to post Share on other sites More sharing options...
shandy Posted September 7, 2016 Author Share Posted September 7, 2016 Thanks Simon, I'd got it in my head that the four roads on the turntable would make it really complicated but actually the wiring is no worse for 4 roads than it is for one. Especially if I use a frog juicer... I use then on the n-gauge layout but it hadn't crossed my mind for the turntable Link to post Share on other sites More sharing options...
shandy Posted September 7, 2016 Author Share Posted September 7, 2016 I prefer the third design, somehow it looks a little more natural to me eye. I think the idea of an industrial line feeding into the layout (as Middleton) is excellent and will offer more interest. I've always been fascinated by terminus stations that have multiple exits like this, alhough probably rare in reality that do offer great operational interest. It really helps with some stock in the layout in order to give some perspective... nothing heard full-size planning! David Thanks I prefer the third design too, I wonder about the release point for the proposed station - it's a RH point, should it be a LH so that the straight road is alongside the platform? should I shorten the platform or buy a LH point.... Link to post Share on other sites More sharing options...
shandy Posted September 7, 2016 Author Share Posted September 7, 2016 The kick back line off the slip on "Scratchy Bottom" goes though a gate that opens and closes and runs off to an off screen industry. In this case a paper mill, the owner of the mill is Mr M R Royds trading as "Scratchy Bottom Paper Mills Ltd." The sidings are used for traffic exchange from the paper mill and the branch. This means I can operate without the use of the fiddle yards if I want. Last year we had 2 3ft boards as the supports fo cassettes this didn't work well and we are building 2 4ft boards to fit traversers to and the 2 spare boards are being used to extend one end. Marc Like the names! I'm sure that paper mill used to supply our school. Link to post Share on other sites More sharing options...
MarcD Posted September 7, 2016 Share Posted September 7, 2016 I forget to tell you the name of the owners wife who's name is on the industrial loco, its "Emma". On the "Scratchy Bottom" thread there has been a whole load interesting names for the private owner wagons. I.P. Freely, Harry Balls, etc To good an opportunity to miss. Marc Link to post Share on other sites More sharing options...
Simond Posted September 7, 2016 Share Posted September 7, 2016 Feed the bridge off a frog juicer. Simple. and expensive... Link to post Share on other sites More sharing options...
two tone green Posted September 7, 2016 Share Posted September 7, 2016 and expensive... But very simple. Two wires in, two wires out, no moving parts, two minutes to set up and only £26. Why struggle. http://www.digitrains.co.uk/ecommerce/dcc-accessories/auto-reversers/DFJ003U-dual-frog-juicer-universal.aspx It may be even cheaper elsewhere. Link to post Share on other sites More sharing options...
Simond Posted September 7, 2016 Share Posted September 7, 2016 Yes, they are simple, and I believe them to be reliable and in that respect, a perfectly reasonable solution to the problem. But, I jib at paying twenty-some quid for something I can do for maybe a fiver, with a few minutes' thought. And the difference is much greater for a typical point. Its a cop-out, IMO. It's your money, and I'd never wish to (and have no right to) say "you shouldn't" but I simply have better uses for the twenty quid difference - it's just a waste, to my mind. Once you've learned to wire a frog, and thought a little about a turntable, you can extend this to the difficult stuff like scissors and tandems. At that point (sorry) you can wire any track formation with a couple of micro switches - and they cost much less than a pound each. (And before anyone says "ah, but you can't do a live frog diamond crossing", you obviously can, unless your layout is a figure "8" with no points - and even then, a treadle would provide the necessary input.) Best Simon Link to post Share on other sites More sharing options...
two tone green Posted September 8, 2016 Share Posted September 8, 2016 No need for cams, relays, micro switches and concerns about sparking. No adaptation of the turntable deck needed so using pick ups and continuous slip rings is ok. No alignment issues. More time to spend playing trains. Simple really. Link to post Share on other sites More sharing options...
Simond Posted September 8, 2016 Share Posted September 8, 2016 Not quite - the sparking issue can occur when a bearing is carrying an electrical current whilst rotating. It can cause erosion of the bearing or the journal that runs in it. This can be the case, no matter however you supply the bridge, if it is live whilst turning. I can't substantiate this, but I believe that AC, such as a DCC signal may be worse than analog DC. I guess that unless you have lights, sound and steam on "max" the current will be very small, so the risk of erosion is probably negligible. But the wiper took no more than a couple of minutes to install. The continuous support rail can be used as one slip ring, of course. You need another feed, which can be a hidden slip ring, or the main pivot. I used the latter. Given that the Metalsmiths kit doesn't come with any "wiring", the builder has to make his or her own arrangements for deck pickups. I rather naively arranged it as a conventional DC analog turntable, and then realised my mistake after I'd done a lot more work. If I'd had the advice that I've given the OP (or I'd thought a bit more, sooner...) I could have done it right first time. It's probably easier to wire the for DCC than for DC, and save splitting the support rail. But only if you know... And like I said, it's your money, your time. Best Simon Link to post Share on other sites More sharing options...
south_tyne Posted September 8, 2016 Share Posted September 8, 2016 Thanks I prefer the third design too, I wonder about the release point for the proposed station - it's a RH point, should it be a LH so that the straight road is alongside the platform? should I shorten the platform or buy a LH point.... Funnilly enough that was also a thought I had. I suppose it depends which side you envisage the platfrpm being on? Do the rear of the layout or between the loop and the siding? Really like what you're doing here though David Link to post Share on other sites More sharing options...
shandy Posted September 8, 2016 Author Share Posted September 8, 2016 Funnilly enough that was also a thought I had. I suppose it depends which side you envisage the platfrpm being on? Do the rear of the layout or between the loop and the siding? Really like what you're doing here though David Thanks for all comments and advice everyone. Initial thoughts are that the platform is at the rear of the layout with a low relief station building, which I think suggests I should buy a LH point. On the turntable electrification question I think a dual frog juicer is my favoured solution Link to post Share on other sites More sharing options...
two tone green Posted September 8, 2016 Share Posted September 8, 2016 Simon, out of interest, are your micro switches make before break to avoid any possible interruption to the deck. I have seen cheap micro switches have a lag in them as they change over that causes decoders to lose power and have to go through the start up cycle which is not very good from a continuity point of view. But you get what you pay for. As for using a track power feed that goes through the movement mechanism resulting in the possibility of power getting back into the motor then strange things can happen, You really will then get sparks of a very undesirable nature. Sorry to Shandy for hijacking your thread but I think you have made the right decision. Link to post Share on other sites More sharing options...
shandy Posted September 8, 2016 Author Share Posted September 8, 2016 Simon, out of interest, are your micro switches make before break to avoid any possible interruption to the deck. I have seen cheap micro switches have a lag in them as they change over that causes decoders to lose power and have to go through the start up cycle which is not very good from a continuity point of view. But you get what you pay for. As for using a track power feed that goes through the movement mechanism resulting in the possibility of power getting back into the motor then strange things can happen, You really will then get sparks of a very undesirable nature. Sorry to Shandy for hijacking your thread but I think you have made the right decision. No problem at all - interesting discussion Link to post Share on other sites More sharing options...
Simond Posted September 8, 2016 Share Posted September 8, 2016 I used a relay, as I said. I'm not aware of any micro switches that physically can connect to both outputs, even momentarily during change-over. The design of them means that the moving contact C simply cannot reach both NO & NC simultaneously, and it is typically sprung so it acts as a mechanical bistable - so it can't "sit in the middle" either. I'm not sure how you can power the deck rails without some kind of slip ring - the power is not transmitted through the gearbox, that would be absurd. Here's a link to some photos & description of my t/t. http://www.rmweb.co.uk/community/index.php?/topic/76732-stepper-motor-turntable-drive/page-5&do=findComment&comment=1328379 Perhaps this will clarify my approach. More lower down and in the DCC turntable thread. I'm sure the juicer will be fine. If you have one, it makes sense to use it. I'm not sure how it will manage a prolonged short if it's used with a split support rail, per typical DC practice. The loco sound will surely go off during the change over. Best Simon Link to post Share on other sites More sharing options...
two tone green Posted September 8, 2016 Share Posted September 8, 2016 Hello Simon, The description of sparking across bearings made me believe you are using a portion the gear box, drive mechanism, drive spindle to transmit power to the deck. Hence my comment about power working its way back to the motor through metal gears etc. But the simplest way is a set of plungers running on two continuous slip rings, no need for breaks in them. Plunger pickups from Slaters are ok or if you want to make some a screw and nut with a spring in between and a plate for the screw to go through. A plastic plate is good enough. Let the frog juice do the work. I have used this set up on my 7mm turntable for a few years now. No issues at all. . Link to post Share on other sites More sharing options...
Simond Posted September 9, 2016 Share Posted September 9, 2016 Hi, thought so! The Slaters plungers on slip rings are a good solution. Probably better than the support rail. Certainly won't get an issue with the sound that way. I doubt the sparking would be an issue, but belt & braces...! Best Simon Link to post Share on other sites More sharing options...
shandy Posted October 30, 2016 Author Share Posted October 30, 2016 Well I've bought the bits I needed to lay the track for my proposed terminus but have now been given permission by the domestic authorities to convert the roof void above the garage into an O gauge railway room. This would give a central area with head clearance of about 3.5m by 4.0m but I could also use the lower areas where the roof pitches down on two opposite sides for non-scenic storage roads and also to extend the run to provide enough space for a continuous run without awfully tight curves. I'm still thinking industrial scene but with branch-line for passenger & local goods traffic. Regarding the minimum radius turns I could get away with on the branch - I've acquired a Gladiator kit for a J25 will I need 6' radius or could I get away with say 4'6" - thoughts would be appreciated. My main dilemma now though is that the garage conversion is probably going to run into the new year, so should I still build something on my baseboards just to run my stock? Might try to build something that I could incorporate into the larger project but not sure how feasible that is. Just when you thought you'd settled on a plan someone makes a bright suggestion that scuppers it.... Link to post Share on other sites More sharing options...
Simond Posted October 30, 2016 Share Posted October 30, 2016 Given the space which you have at your disposal, I think I would tend to sort out insulation, access and flooring to your satisfaction, then baseboards, then lay track. Whilst certainly possible, I doubt it will be easy to incorporate a "pre-built module" into a loft layout, so I think I'd tend to avoid that, but of course if your access is easy, it might be a good solution to allow running something, sooner rather than later. There are lots of layouts around with 4'6" curves. Locos, particularly with outside motion & bogies, can be an issue but you can avoid these. A more general problem with tight curves is couplings. They have to be long to accommodate the corners, and then look odd on the straights. This is particularly noticable on tender locos of course, but also affects coaches and long vans, which are also susceptible to buffer locking. My tendency would be to set a ruling minimum radius and stick to it. If you're going to use Peco points, they're about 5'6" minimum, by way of reference. Edit - sorry meant to also say that Gladiator's new proprietor, David Hill inhabits these pages and can surely advise re the loco in question. Hth Simon Link to post Share on other sites More sharing options...
shandy Posted October 30, 2016 Author Share Posted October 30, 2016 Given the space which you have at your disposal, I think I would tend to sort out insulation, access and flooring to your satisfaction, then baseboards, then lay track. Whilst certainly possible, I doubt it will be easy to incorporate a "pre-built module" into a loft layout, so I think I'd tend to avoid that, but of course if your access is easy, it might be a good solution to allow running something, sooner rather than later. There are lots of layouts around with 4'6" curves. Locos, particularly with outside motion & bogies, can be an issue but you can avoid these. A more general problem with tight curves is couplings. They have to be long to accommodate the corners, and then look odd on the straights. This is particularly noticable on tender locos of course, but also affects coaches and long vans, which are also susceptible to buffer locking. My tendency would be to set a ruling minimum radius and stick to it. If you're going to use Peco points, they're about 5'6" minimum, by way of reference. Edit - sorry meant to also say that Gladiator's new proprietor, David Hill inhabits these pages and can surely advise re the loco in question. Hth Simon Thanks Simon I think you are right about pre-building something - it's bound to end up as a compromise, might knock something basic up just as a test bench for my loco's in the meantime - the rolling road is just not doing it for me! Longer term I envisage running mainly small to mid size locos the J25 and possibly J27/G5 would be as large as I would go, as far as coaches go I've a mind to restrict myself to nothing bigger than Connoisseur 6 wheel coaches, will definitely use Peco track and points for storage roads possibly even for the scenic lines, although one of my friends has gone with Marcway track which looks very nice. Thanks again Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.