Dan6470

some shots i took in 2006, not the best quality they were taken on a mobile phone, Chris Hewitt and John Holden working on the track..

 

 

Mike

Wow, I have just spent the last days reading through this thread, like everybody else I'm very impressed and take my hat of to you and the team.

I have tried to access the old RMweb pages to see the early stages of Lime Street Station but unfortunately it doesn't seem to be available at the moment but I do appreciate the above photographs. May I ask what the baseboards are constructed from and also the platform edges, they look like pine but with the shape you have, perhaps not.

Thanks

Dan

Hi Gordon

That was fast, thanks very much.

The slip so far. This is a 1:8 double slip with a switched crossing.

I perhaps don't understand what you mean by a double slip with a switched crossing, is that a switched crossing within the double slip. If that's the case then I'm probably going to be confused. Before asking any more questions I'll wait until you complete slip and hopefully you'll post a photograph that will explain all.

Once again thanks.

Dan

Hi Gordon,

Smashing photograph of the N2, you look to be making quick progress and I see that you've committed yourself to the building of a double slip - wonderful stuff. I know that you've been a little apprehensive about the double slip and perhaps doubting yourself a little bit but I've got faith in your abilities, I've seen the beautiful trackwork what you've produced before.

If you have a opportunity to document the construction of the cross over and double slip it will be invaluable, well certainly to me!

Best regards

Dan

Well that's a great idea SG, but still quite difficult to achieve. If travelling in a clockwise direction, a 45mm height difference will need a run of 4.5m and then once on the same level, you'd have to cross all the running lines before you start to run into the storage loops. Even if this were possible, it would then mean another trip round the layout or some back and forth light engine work to access the shed.

Gordon,

Nice to see you progressing with ET. With reference to SG's point about freight locos accessing the shed, do you think it is really necessary for such a shallow gradient 1:100. I know in the past you have made a number of experiments/tests, same as myself, in which the conclusion was a minimum gradient of 1:100 for the movement of stock but if the only movements over the gradient would be light engines perhaps the gradient could be increase to, say 1:75? As far as I can see the only negative would perhaps be a future desire to move coal wagons down the incline to feed the engine shed. Just a thought.

Dan

Hi Gordon

Thanks for getting back to me. I had a feeling that the lower loop was to feed storage tracks.

I'd like to add back some of the retaining wall element that figured so strongly in Eastwood 1 and include at least one overbridge as per Holloway Bank and Kings Cross.

 

Hope this all makes sense...

 

I've got to say that those retaining walls looked superb and with your step by step instructions appeared very easy to build. Keep up the good work.

Best regards

Dan

Hi Gordon,

Good to see work progressing. Hopefully you won't mind me asking a question.

With reference to the revised plan in a previous post, it seems that the inner two tracks of the quadruple track from the new junction goes up to Eastwood Town and the outer two tracks return to the turning circle. Are these to be used for storage or am I misunderstanding the diagram.

Dan

Hi Gordon

Good to see work progressing;

but with 50,000 views someone must be looking at it. I actually find it quite therapeutic scribbling down a few notes and adding a couple of pics.

that's because a number of us have probably set Eastwood Town as our home page in Firefox/Internet Explorer/et al and where you find it therapeutic, I'm sure, others find it kind of addictive. But to be serious for a moment, there is a wealth of information that you are sharing here and your methodology and relaxed attitude as Grimleygrid put it are indeed admirable. Although I cant get over the octagonal on the dinning room table ... wow

Also, like Pete, I was very interested in seeing a close up of the switched crossing. Have you designed all the double junctions with switched crossings? I had never knowingly come across them until Eastwood Town but there again my knowledge base is in its infancy.

Keep up the good work but take care of the back first.

Dan

Hi Martin,

Thanks for the info ... I sure am learning a lot here;).

Dan

I did get some from C & L, although I also got some from Mainly Trains in the early days. I've just bought 100m of rail from C & L as they had some on offer. It's the same material as SMP but the C & L width. £35 for a 100m. Seems perfectly OK.

Hi Gordon

I trust that will be the 4RA201J Code 75 Nickel Silver, 12% NI, Bullhead - 100 yards. £35 seems a pretty good price.

Dan

Hi Gordon,

Thanks for getting back to me. I too have considered the adoption of 00-SF for my turnouts, the arguments/justification seem to outweigh any negative aspects. Although it does seem strange that the Roller Track Gauge and the Check Rail Gauge haven't been milled onto the same gauge as with the gauges in your photographs. A shortage of the roller track gauge for 00-SF will probably cause me to go towards the DOGA Universal/intermediate gauge.

With regard to your brass Roller Track Gauge/Check Rail Gauge did you obtain it from C+L,? I understand from a previous post that you construct your turnouts using C+L components having previously found that the SMP rails measure 0.82mm as opposed to 0.92mm for scale BS-95R bullhead rail. I'm assuming that SMP gauges are set for 0.82mm rails.

Dan

Hi Gordon

I don't understand why the photos didn't show up but the post that I refer to is number 28 on the second page of Eastwood Town.

But here, hopefully, are a couple of the photographs.

Dan

Hi Gordon,

I've been following your progress with great interest and appreciate the difficulty that you've had over the last weeks with your injury. Nevertheless the description of your methods for track construction is very encouraging for those modellers that are wanting to try to construct their own turnouts but haven't done so yet, I include myself amongst those modellers. We have communicated on the subject previously but just now reading through the Eastwood Town - Update I have a couple of questions that hopefully you can help me with.

Now, there are several ways of making pcb track and this is the one that works for me. I'm not suggesting that this is the right way and it's not intended as a teaching exercise. I said at the beginning that the critical part of a turnout in my experience is the check rail distance from the crossing and not the actual track gauge. When I first started making my own track, I was gauging the outer rails from the crossing and then setting the check rails from the outer rails. Having now read a lot more about track issues, I changed my assembly method to set the check rails first, so the next thing is to cut and form the check rails and then gauge them from the crossing rails.

 

 

 

The next stage for me is to now add the outer rails. The important thing for me is the smooth flowing lines of any trackwork and whilst Templot is very good, I also use my own eyes to check that the rails are in a nice flowing curve and do not have any minor kinks. I only tack solder every few sleepers at this point in case something is not quite right.

 

 

 

 

 

So that just leaves the point blades to be filed. These are done by hand using a needle file. Once formed and cut to the correct length, these are gauged from the outer rails. To simplify things, particularly on hidden turnouts, I just use PCB strip as a tie bar, replacing one of the normal sleepers. The ends of the blades are carefully gapped using the 1mm shim and then soldered to the tie bar.

 

 

 

.....and basically that's it. A custom built curved turnout that cost a fraction of a RTR one and took less than 3 hours to build. The last job is to check all is OK and then solder the rest of the sleeper/rail joins and lighly cut through the copper strip with a slitting disc to isolate both rails.

 

 

Making pcb track is not that difficult once you have the right tools. A set of gauges, a decent soldering iron and a bit of patience is all that is required. It's a great way to spend a few hours and very rewarding once you have finished.....Add to that the cost savings that can be had and the freedom it gives in layout design and it scores all round.

 

Go on, give it a try....

From the above photographs I notice that each of the gauges that you are using have four grooves in them. I'm assume that the gauges can be used as roller track gauge and also for check rail gauge. Can you please confirm? Also can you please advise what standard you have adopted. Clearly high, I mean with regard to the gauge DOGA intermediate, which I think they call universal now, DOGA Fine or 00-SF.

Thanks

Dan

Ps. Do be aware that any answers you give will probably result in further questions

From memory - I don't have the circuit in front of me, and I'm trying to sort out a PC problem (read one message in Outlook and it freezes, needs CTRL/ALT/DEL to stop it then restart, worse problem than the old RMWeb!) - I believe the circuit to be a PWM with adjustable feedback. Based on the then new drill speed controllers. Has the option of adding accelaration and decceleration. Built in overload protection (simple bulb). For my uses I've "designed" (if thats the word) a veroboard layout, with a handheld contoller box (speed control, direction switch) coupled to a fixed main unit (the majority of the circuit). Components such as transistors are dated, but modern equivalents are available. I've plenty of stocks so haven't needed to source new. There is a 2nd potentiometer, mounted on the main unit, which the article describes as a "max speed" setting, but I find it better to fine tune the "min speed" setting with this. Seems to work ok over a range of motors, though the pedantic might adjust it with every different motor! To be honest I'm not up to speed with the latest types available, I've found this one suited my needs for all these years, if it ain't broke don't fix it, so I've not bothered to look elsewhere. You're welcome to a copy of my notes, if it suits you, fine, if not, well nothing lost.

Hi Stewart, No hurry at this end, still redecorating the "Railway Room". Then I've got to build the baseboards, build the track, lay the track and ballast before I get anywhere near the electrics. So no sweat, sort you PC out then I'll be very happy to see your controller.

Dan

I am interested in the Wireless World and will arrange a copy, without seeing it I would assume PWM in base, as no other way gives such control. Feedback can help slow speed, but most aim at constant speed for gradients, Codar used to make one, and I have the circuit stored, but it is not wonderful on crawl. It was an early user of momentum effects.

It would be fine for larger layouts.

 

All feedback controllers are lost with multiple motors, banking, US units in tandem or more, the intermittent contact that must occur despite all efforts to keep everything spotless and all wheel contact, will lead to lurches as the tiniest feedback signal is used to correct what has not happened.

 

Now I hear the man at the back saying he uses feedback with multiple motors, and in real life the makers of the units add hysteresis to the circuit, sudden changes do not cause sudden jumps, but some locos may still be sensitive and react, and the choice of the lag is critical, too much damping, and you might as well have no feedback.

 

Personally I do not like feedback where there is a large amount of different locos to run, as they all behave differently, only slight, but it is there......and my feeling is that you are the driver, and should be in control on gradients anyway!!.......

 

To get the best of both ways, do not modify one type or the other, just have both and switch in as needed, A regulator based 0 to 12vdc, with pure DC(handles anything in sound order)., a PWM for shunting, and maybe a feedback type for mainline loop running on a big layout.................or buy DCC...........trouble is the word BUY...............DCC is very pricey indeed, as all three circuits coud be built for about the cost of a single Lenz decoder.

 

Also as before, join MERG it is the source of a lot of help, and masses of experience, although prepare to have your arm twisted towards the dark side, DCC.........there are those in there who still resist it though.

Hi Stephen, I appreciate what your saying, very difficult to find one controller that can do everything but maybe, just maybe, the following link may prove interesting.

http://www.freepaten...com/3994237.pdf

It's based around a saw tooth waveform with pulses superimposed on it and as the saw tooth waveform increases towards maximum output the pulses are switched off. I'm not too sure at what Frequency the pulses are, produced by a multi vibrator and are adjustable via a variable resistor, but it looks interesting and incorporates a feedback circuit for continuous output and an overload protection circuit. So ticks all the right boxes.

Have a look and see what you think.

Dan

Hi all, Sorry for the delay in responding to your posts but nevertheless I do thank you for the time and trouble you have gone to in answering my questions.

I use a DIY circuit from Wireless World 1973, have built quite a few of these over the years. Fairly complex, but very good. My Wills J69, with a 5 pole motor and 60:1 gearing takes 30 minutes to traverse a 1/2 circle of Hornby track. My old Triang 0-6-0 chassis as built can been seen, with the body off, to show the motor "cogging" over between poles. I've scanned & rewritten the article to aid me to construct the units on a production (!) basis if you want a copy?

Hi Stewart, 30 mins for 180° sounds good, I would love to see the schematics/article if you can post it or even pm me the details.

Dan

 

You may want to look here for some controller ideas (and plenty of other info to distract you!):

 

http://home.cogeco.c...rcuitIndex.html

 

But to answer your question - I built this a few years ago:

 

http://users.rcn.com...tcl/ccartcl.htm

 

which ticks most of your boxes and was used extensively on an American HO modular club layout, hence had to cope with a wide variety of mechanisms - old and new.

 

The only changes I made were to the momentum resistor values (as suggested in the text) as we found for our purposes there was too much delay/momentum; you could practically go off and make a cup of tea

before some locos really got going! Hence suggest fine tuning values to suit. Controller worked well and has now been passed on as we graduated to DCC....

 

John

Hi John, thanks for the your post and links. Through the research that I have undertaken I am familiar with the circuits of Rob Paisley, by that I mean that I have come across them, and as you say it is quite easy to get distracted when you start to look at his ideas.

The TechTronics circuit is also quite interesting. Simple in its operation, it would seem that the control is just through the manipulation of the amplitude of the 120Hz, or in our case 100Hz, rectified waveform. Does it have any overload protection? I can see that D4 provides current limiting but I’m not sure if this would be faster enough in case of a short circuit. How have you found this in practice? Also, since my proposed layout will have some gradients, I would like a controller that can maintain a constant speed and I assume that this would have to be through some form of feedback. Perhaps this could be added to the circuit, it’s certainly food for thought. Thanks very much.

There are lots of suitable designs on the net, but as you say how do you know what they really do?

 

 

I know, as an electrical engineer, but even then the circuits may not work as expected, so it needs recommendation, and the best course is to join the MERG group, who are a club, shop, group of enthusiasts etc, and have the experience to say what works and what does not.

 

Your requirement is for control of older "type" motors, none the worst for that, straight DC, with feedback may be the best, with variable pulse available in a switchable form. It would be the same for an all Mashima fleet, they just have lower draw on current.

 

Feedback works where a fleet are basically the same motors, otherwise it has got to be in some way adjustable. Double motored locos cause problems with feedback and don't work with the set-up.

 

The best control for low speeds are variable mark space CV (constant voltage) controllers, but if the motors are 3 pole and 5 pole on the same layout there may be differences, and such controllers are able to make the motors hum due to the pulses.

 

The next best are feedback controllers, which can be CV mark space types or pure DC, or a mixture, a circuit that senses the load and back EMF, trying to maintain a constant current drain, again when pulses are used the motor may hum at low speeds.

 

But after all the extras are removed a pure DC supply is able to run any type of motor without hum, and straight forward variable voltage regulator chips, which have built in overload protection are the best all rounder.

 

Commercial designs try to deal with as many variables as possible, so building your own can fine tune to what you have much better. It is also very inexpensive,... £10 would build a comprehensive spec., controller, with the exception of the transformer for power, the most expensive item.

 

hope this helps,

 

Stephen.

Hi Stephen, thank you for your post. I haven’t come across any double motor locos but would assume the same problem in double headers. You mention the variable mark space CV (constant voltage) controllers causing hum but, may be a stupid question, can’t this be resolved by using a higher frequency for pulses, as mentioned in my original post, 20khz or above?

You can build this one yourself, or buy it ready-made through ebay ( I chose the second route) - and I highly recommend it - an excellent device for DC control which will be used on the Harlem layout

 

http://www3.sympatic...pleton3/851.HTM

Thank you Jack, the PWM walk around throttle is interesting. It would seem that PWM lends itself to slow running which is one of my criteria but I have to try and eliminate the hum that Stephen mentions. Once again thanks for your post.

A Full PWM type circuit, (Constant voltage), very interesting, I use Mr Penfolds version, (in Bambini books on the 555) with 555's generating the pulses, resulting in exactly the same square wave forms.

 

This type works very well indeed for control. especially shunting, but as the other postings on the US design for variable voltage with pulse say, it can over heat the motors, but only under load on long runs on the main lines, light load, and short runs no issue. Crawl control cannot be bettered with PWM, no way any other circuit can be superior, but only at these low speeds.

 

 

Such PWM controllers can make some motors hum and noisy, again it varies, well set up motors do not mind, but add loose bearings, and dry gears, and you have noise, add tight gears, resilient mounts, and grease lube, no issue.

 

My own mods to the 555 driven type of PWM are to raise the frequency and use capacitors to smooth the output, which are switchable to suit different motors, this also reduces potential motor heating as the RMS value of the output is lowered.

 

Motor heating is not serious on PWM as such, it is after all nothing to do with applied voltage, it is the average current drawn under load, less efficiency, that is the heat source, not the higher voltage pulses, as nothing is applied at all in the gaps!!

 

But yes, under load the magnetic field behaves dynamically, and despite all theory, the motors heats up more on square wave pulses, than plain DC. The motor operates on the average of the pulses, but the mean value is not linear as the load increases and more inefficiency occurs...result heat. The back EMF is also high with pulses, and contribute to the heating, as with coreless motors, which should not be used on PWM, they can burn out in extreme load conditions,.

 

Coreless are often driven by PWM signals in electronic equipment, but are in constant known load limits, and are quite safe then.

 

Therefore PWM CV type controller...perfect for micro layouts and switching layouts...not for large club layouts with legions of locos of different types.

Stephen.

Hello again Stephen, you mention using a 555, I assume 555 timer. How far have you increased the frequency? Is a practical to go to 20Khz with a model railway throttle? Your last comment here “Therefore PWM CV type controller...perfect for micro layouts and switching layouts...not for large club layouts with legions of locos of different types†perhaps there’s a way around this problem with a switch that will switch out the PWM circuit and revert to a DC throttle. Thing is, I’m totally in the dark here. I recognise that I’ve got to do some experimenting here but I would much prefer to be lazy and be spoon fed. No, it’s not that I’m a Yorkshire man ... we're just tight careful;)

Dan

Hi,

I'm in the process of planning my model Railway, OO gauge. The railway will be composed of a Junction and Terminus stations with goods yard and loco sheds. Presently, I'm only interested in using conventional DC for control of the locos. A fair proportion of the locos are Hornby Dublo, so I would anticipate a need for more/greater current to run these old locos. I would like to build my own controllers and ask if you have built your own controllers whether you would be willing to share your experience in this regard.

From the research that I have done, it would seem that the better/best controllers use various forms of pulse power in order to achieve slow running but I am aware that this can cause over heating and noise. I had initially thought of using an unsmoothed, full wave rectified wave form to trigger the pulses which I think should produce 100Hz but is this reasonable or should I use a much higher frequency to reduce motor noise? 20khz comes to mind;) Also, since it is almost inevitable that a short circuit will occur at some point, then of course I need to plan some sort of protection circuit for current limiting into the controller.

I also propose to integrate negative feedback into the controller whereby the back emf of the motor can be sampled and used to maintain a constant speed. As mentioned a number of the locos are Hornby Dublo, so perhaps not the best valve gear, and my layout will have some gradients. So I think I will find Negative feedback invaluable.

There are a number of books available for model railway electronics but the problem here is that there is no feedback from the readers that indicate whether a circuit is good, bad or simply unusable. So any pointers you can give would be most appreciated.

Dan

Why build a model railway when we can watch Eastwood Town ............... double wow!

Can we have some video please?

Dan