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Izzy

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Posts posted by Izzy

  1. Given that postal orders no longer exist AFAIK and the vast majority don’t have cheque accounts, electronic means of some kind for payment are needed. I see you can now order online, and then pay via credit/debit card, BACS, or PayPal, following an invoice, so it seems Squires are covering these problems. Given the vast range of small bits and pieces they stock perhaps this is more managable for them if they don’t have the resources to be able to generate and maintain a ‘live’ stock level system. This also seems preferable to me than ordering and paying from e-commerce sites that don’t have current stock levels where items are o/s which then gets frustrating and annoying if available elsewhere. 

    • Like 2
    • Agree 2
  2. Thanks for all that info @Nigelcliffe, that’s very helpful info for anybody with one of these. It’s such a shame CT are no longer around as I see it’s giving the NGS problems with trying to complete the orders it has for them. I am minded just to thin the flanges and leave it at that seeing as there is quite a bit of body overhang all around to help disguise the wheel width. Thinning them means faffing around with repeating the recess for those brass inserts. 

     

    Yes, reducing the Prodigy output is being worked on. Though adding another CB isn’t at present given the last time I tried it the PSX duffed over the base station and I now understand Gaugemaster are no longer undertaking repairs of any kind with them so I don’t want to take the risk.

     

    Bob

  3. 1 hour ago, Caley Jim said:

    Speak to @Nigelcliffe.  He's working on how to convert them to 2FS.

     

    Jim

     

    Having had a look at the evolved wheel design used this evening (compared to the last Farish split-axle locos before the return to wiper pickups) I think a re-machine of the wheels will do the job.  They appear to be central castings ( I don't think they are plated machined brass but they might be) with large rear stub axle and an etched brass spokes insert, so thinning the flanges and reducing the overall wheel width seems possible. 

     

    Bob 

  4. It's a funny old world sometimes isn't it? After lunch today I popped to my nearest WHS to get MRJ 301. I also took the opportunity to go into the art & craft shop to get a couple of bits, drills & glue, and came out as well with this, which was quite unexpected.

     

    RMwebNGSHunslet01.jpg.c10f6b9172d833b613fb0528f0f3a1c4.jpg

     

    They do stock some railway modelling bits and it was in the cabinet for sale at the same price the NGS is currently selling them for. Bought by someone associated with the shop but never opened or run. I'm not a NGS member so have never considered getting one, but looking at the little thing, knowing it was decoder + stay-alive fitted, how could you refuse? 

     

    RMwebNGSHunslet02.jpg.d41d25ec00782a09c0fd5b805d6f8ada.jpg

     

    You can see the family resemblance alongside my Hunslet 05.

     

    RMwebNGSHunslet03.jpg.17825a62f19f6404cc0cb5821ac21713.jpg

     

    I just gave it a brief run on the odd piece of track via a 9v PP3. Runs very nicely.  Of course being me I couldn't resist just undoing the odd few screws  .....

     

    RMwebNGSHunslet04.jpg.5e0a4a08113d2a1498440673d51f0773.jpg

     

    The quality of the design shines through. So neat and clean in all aspects. Now all I need to do is remove those horrible couplings, fit some DG's, oh, and work out how to convert it to 2FS! I suppose a bit of weathering might also happen ....   Then work out how/when to run this very rule 1 purchase...   A tiny shunting plank might be called for perhaps.

     

    Bob

     

    • Like 8
  5. 2 hours ago, Nigelcliffe said:

     

    You could drop the track voltage with a string of diodes.   One pair of back-to-back diodes in one of the track feed wires will drop about 0.7v.  So, three pairs would drop things to 14.9-2.1=12.8volts.   Fast rectifier diodes, and 4A or 5A rated given your DCC system's output.  

     

    I had thought about doing something like that, Nick Mitchell suggested reducing the track voltage when the first 16v tantalum went bang some time ago, but I wondered if it would have any side-effect on decoder performance in respect of motor control so didn't take it any further. 

     

    Thanks for highlighting how I might achieve it. Would you have any code numbers for suitable diodes Nigel?  I presume you mean fast recovery diodes. I've had a look around but as usual the more I look the more confused I get ....

     

    Bob

    • Friendly/supportive 1
  6. 1 hour ago, Jan W said:

    Do you know what track voltage your dcc system gives?

    If it is around 16V or maybe more, could it be an idea to try to reduce it to approx. 12V?

    Safer for the capacitors. The zener still limits the voltage on the capacitors to the max. value.

     

    Jan

     

    Thanks for the thought Jan. It's 14.9v. As it's a Prodigy PA2 system sadly there are no adjustments I can make. It's a very limited/closed system - expensive for what it is today where the Z21 would be my choice - but as I only want it for loco control I stick with it because the 3.5 amp output gives plenty of overhead for powering the hacked servos etc. through a voltage regulator (plus I have a wi-fi handset).  

     

    Bob

     

     

     

  7. Stay-Alive.... or not!

     

    Those who believe there is no such thing as coincidence might find the following quite funny considering only yesterday I posted on Doncaster Green's thread about not fitting stay-alives to plastic bodied locos because of issues with odd 16v tantalums.....   I wasn't quite so amused....

     

    Today I went to run the Hunslet 05. I would put it on the track and then after a brief interlude my DCC system would say there was a short. ????  After playing this game about half a dozen times I realised there had to be something wrong with it since with any other loco all was fine. Hm.

     

    Since locos don't just develop shorts for no reason I came to the conclusion that something on the electrical side had failed. The motor, the decoder, or the stay-alive. Something told me the time it took to register as a short tended to point to the stay-alive, but you never know. 

     

    Nothing looked amiss once the body was off, but the chassis alone still gave a short when placed on the track confirming my initial diagnosis rather than a breakdown in insulation between the body and chassis. Working backwards from how it was put together it seemed the best way to track down the problem was to disconnect things in reverse order, stay-alive, decoder etc. A process of elimination. Once the stay-alive was removed it all worked. Okay, well that was helpful in that it wasn't the decoder or motor, but, oh bother....

     

    So then I stripped the stay-alive down to the individual parts to test them. Zener, resistor, schottky diode, plus the three 220uf tantalums. I had plenty of bits to make another to replace it but I wanted to first find out why it had apparently failed and what had gone wrong. 

     

    With my basic old Maplins multimeter I tested all the bits. Another of the D case Tantalums had gone belly up it turned out. Not with a bang as before thankfully in this case but with a wimper just becoming open so current passed straight through. So not a disaster, just annoying

     

    Since I had obtained some flat 470uf tantalums which I had used in the J69 and J15 rather than re-build the stay-alive with more 220uf D case ones I chose to produce another using one the advantage being it would be slightly smaller in size in width and height, and 470uf had proved enough. I do hope this doesn't become a regular chore and more of these D case 220uf tantalums fail. That would become really tiresome. 

     

    Bob

    • Like 1
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  8. 35 minutes ago, Caley Jim said:

    I fully agree with @Izzy.  There's absolutely no need to use the biggest motor you can fit, in fact I would say the opposite.  Fit a small motor so as to leave plenty room for stay-alive capacitors.   The majority of 2mm Locos will run out of adhesion long before the motor runs out of power.

     

    Jim

     

    Since one of the 16v tantalums in the 2MT went bang non of my plastic tender locos now have stay-alive (except the re-built Royal Scot where there was the room to use 25v tantalums so way above the track power level) on the grounds I didn't want to end up with a melt damaged body.  TBH with six wheel per side collection they shouldn't really need them. Non of my bogie diesels has them either. But I have tried one in the J15 just to see if there is any noticeable difference/advantage since the tender wheels are perhaps a bit iffy. 

     

    Bob

  9. 1 hour ago, Doncaster Green said:

    Agree.  Shouldn't be pushed for space in a Group Standard tender, although the intention is to cram in the biggest motor I can!

     

    John

     

    Hi John,

     

    In recent times I have pretty much standardised on the 7x16 size coreless motors as a 'one-size-fits-all solution', having used them in everything from the little Hunslet 05 to the slightly bigger re-built Royal Scot with no power issues at all. These have been both the cheap ones off eBay from past times and those now in shop 3. They seem to cope with whatever is thrown at them, which using DCC just builds on, and the deciding factor on haulage is purely down to weight/mass. Use one of these along with a ratio of 30/40-1 and fill the body with lead and you should have no problems. *

     

    Bob

     

    * and it goes without saying a Zimo 

    • Agree 2
  10. 28 minutes ago, ITG said:

    I think you’re correct. I started with (still have) a Prodigy Advance2 but graduated to a Z21, not least to provide detection capability.

     

    In which case @Robin C will need to confirm this with say James at DCC Train Automation before going any further. Having to change to another DCC system will I have no doubt help decide what other parts to go with it will be best. 

  11. 13 hours ago, D-A-T said:

     


    Bradfield Gloucester Square springs to mind. Lots of videos on YouTube showing the variety of traffic and the ebb and flow during the day.

     


    Yes, it’s really good, but is a significant enlargement on Minories with the multiple carriage sidings etc. which are the key to its operation. In recent years I have come to realise that decent large capacity fiddle yards are a must for single user layouts if you don’t want to spend more time just continually changing stock in them to run the most simple of sequences when the layout track design doesn’t have the capacity. It’s different if two people are involved and one just works the fiddle. 
     

    Bob

    • Agree 1
  12. 2 hours ago, Flying Pig said:

     

    Doesn't your 2mm layout do just that in a slightly smaller station?


    Yes it does, indeed it’s been far more successful in providing the scope for wider operations than I could ever had envisaged. I just like the idea, the challenge, of making an original design folding baseboard Minories that could give a similar level of operations since my first truly worthwhile layout was a small folding baseboard design. 
     

    Bob

    • Like 1
  13. I'm of the opinion that in the early days most layouts placed operational use at the forefront of their designs with just mostly token scenery within the railway boundary unlike today where the opposite often exists with many and the railway side seems almost incidental to the scenic one. 

     

    To my mind Minories falls into the former category and I still often think I would like to build a minimal size version but get stuck at wanting to expand the range of trains to make it more interesting to operate. How to do so without expanding the track design much or having more platforms. Different types of traffic rather than just more of the same. That would I feel get boring to operate quite quickly for a lone modeller such as myself.

     

    Bob

    • Like 1
  14. First off you really need both a resistor and diode in circuit and in addition a Zener will help limit the current to the capacitor. If you look around online several circuit diagrams and component suggestions will be found. I use a 100R SMD resistor combined with a Schottky SMD 40v diode and a 16v Zener.

     

    As to decoders well, I now only use Zimo. The MX600 at £25 is still available and will be far better. 
     

    Bob

  15. J15 with two speakers

     

    Well, it's been a while since I last posted on this thread. It isn't that things haven't happened, All Saints East itself has been completely rebuild for a start, and new items in the form of a couple more locos added, but the main focus has been elsewhere with another scale/gauge.

     

    However the making of these new locos and fitting them with sound, (a J68 from an etched kit and a Thompson L1 using a Hornby body on an etched chassis), brought to my attention that the only tender loco, the converted Hornby RTR J15, didn't sound right with the sound clearly coming from the tender and not the loco. This wasn't readily apparent when I first fitted sound to it after the conversion to P4 but slowly became apparent over time when run alongside the other locos.

     

    The question was, what to do about it? I'm afraid I am one of those people that can't leave things as they are if I find something that's not right and isn't to my liking. There was nothing wrong with the sound, the J15 project from Youchoos, indeed it sounded great (and stills does) with a few tweaks for personal preference for individual sounds levels.

     

    Now I'd fitted sound to both these new steam locos by fitting speakers into their smokeboxes and it began to occur to me that this was what I needed to do with the J15. With a speaker already in the tender and having read and posted questions about twin 8ohm speaker set-ups it seemed quite possible to do and especially as I had fitted a Zimo MX645 which can cope with this in either speaker wiring formation of series or parallel, having a 4-8ohms output. Speakers wired in parallel halve the impedence while in series this doubles. So two 8ohm in parallel are 4ohm while in series it becomes 16ohm. It seems the lower the impedance the louder they are and visa versa. The speaker impedance must obviously match or be less than what the decoder can provide. So in parallel is not possible for those that can only provide 8ohms, which is the vast majority of Zimos. ESUs are all 4ohm I believe.

     

    The big issue was finding the space. The Hornby J15 has a cast metal footplate and upper body in two halves for weight which is great but what space remains is stuffed with the chassis and motor etc. There is no empty space at all. Eventually after measuring it all up I realised I could, just, squeeze one of the small 15×11mm planar speakers I have used recently into the smokebox standing vertically, but only if I was able to cut out the large chunk of metal that sits there behind the smokebox door.

     

    RMwebJ1569.jpg.305ee8635dce95e795babb5207927e34.jpg

     

    It took me quite some while to pluck up the courage to attempt this, the ever present danger of just wreaking the complete loco not being far from my mind. Because finding a spare body would not be easy (probably impossible) should things go pear-shaped. Trying to work out how to actually cut out this metal section also took some time. If only the smokebox door came out…..and I could get the boiler/cab off the footplate….

     

    In the end one day I just took the plunge, parted the loco and tender, and took the body off the chassis. After removing the screws under the cab floor I managed to slowly lift the cab away and by gently levering the cab/boiler up/down it started coming away from the footplate. It took a long time as I didn’t want to bend/warp/crack the footplate. The front slips under the footplate and this is what the chassis screw goes into. It was the middle part of this tall square pillar I had to remove, well almost all of it actually except the very bottom bit with the screw hole.

     

    As there was a gap either side which shows the rear of the smokebox door I decided to push my luck and see if I could force the door out from the rear. I guessed it was glued into place. It’s plastic, one of the few parts that are. Just when I was about to give up it flew out of the front with a crack and ended up on the floor feet away. Given the sound made I thought perhaps I’d smashed it, but no it was intact and undamaged. That was lucky!

     

    RMwebJ1570.jpg.aa0fd8131057d68059e4c75251685e8b.jpg

     

    RMwebJ1571.jpg.e151407ecfb0c38fce45cc356e34c66c.jpg

     

    RMwebJ1572.jpg.9bd684c91c13ca5496e21e9b8b3b873b.jpg

     

    With it removed there was then easy access to the pillar and so I chain drilled it top and bottom to remove the bulk and cut it out and then spent a long time cleaning it all up with burrs in a mini drill and to get the square corner shape into which the speaker would fit. I had to cut away the pillar below the front of the smokebox which was a tricky task to complete.

     

    RMwebJ1573.jpg.6f3d13c51e3b750006abd58c963a893f.jpg

     

    RMwebJ1574.jpg.427786ee835d502b7c8d2de10f8e8c83.jpg

     

    Once done it proved possible to get the speaker into the space but only a flat piece of plasticard could be added onto it to make a sealed enclosure.

     

    RMwebJ1575.jpg.bd14d11e21e4f93db64d251ed7442104.jpg

     

    RMwebJ1576.jpg.31dacb3a3627184eb9012a9fb55411a8.jpg

     

    After soldering on the wires I wrapped it in Tamiya masking tape for insulation against the body, not wanting electrical shorts of any kind. This tape was also used to hold the wire runs to the inside of the boiler.

     

    RMwebJ1577.jpg.1c24bd1045451a275a7bbaacda1f06da.jpg

     

    Initially when all done and wired up I found the larger Zimo speaker in the tender still overwhelmed the other volume wise, so replaced it with another 15×11 planar to get an even sound output. This worked nicely. Now it seems as if the sounds come from the loco itself whichever direction you listen from. So a lot of hard work but worth the effort.

     

    Bob

    • Like 1
  16. 12 minutes ago, irishmail said:

    Very strange looking at the March Railway Modeller and seeing no Hatton's adverts. 


    I guess all the magazines are going to miss the annual advertising income Hattons used to provide, the often multiple pages. 

    • Agree 7
  17.  

    Experiments have continued. It seemed just adding the small planar in the smokebox didn't really have the desired effect, the sound volume of the larger Zimo dumbo in the tender overwhelming  it. It was better, but still noticeable.

     

    So then I removed it and fitted another of the 15x11 planars in it's place, the idea being they would/should match and thus balance out better. This seems to have worked out. The sound now just seems to come from the loco as a whole rather than a specific area of it as before. This might be helped by the fact the one in the tender is right at the rear of it to match/counter the loco one being right in the front. This is good given all the work I had to carry out on the loco body to obtain the space for the speaker. 

     

    Even in parallel at 4ohms however the volume level output couldn't match that of the single Zimo dumbo at 8ohms.  I had it set at 20 (cv266) for my needs in a small room and have had to increase this to 60. Part of this might be because there was no room to add an enclosure to the smokebox one so I didn't with the tender one either so as not to skew too much the balance I was after considering the space in it to act as a soundbox anyway.

     

    Bob

  18. 8 hours ago, Albie the plumber said:

    The greater the impedance , the quieter the sound will be , therefore, wiring in series doubles the impedance  , wiring in parallel halves it .

     HOWEVER ,Wiring in Parallel may well damage the amp on a decoder if the impedance is half the recommended impedance on a decoder .

    Many ZIMO decoders are 8 Ohm impedance so will not be suitable for parallel wiring .

    sometimes , sticking with one speaker of the correct  impedance is the best option.

     

    HTH 


    Yes, it does, many thanks. Luckily the Zimo concerned is a MX645 which can do 4-8ohms. So it looks like parallel will be what gets wired in. 
     

    Bob

    • Like 2
  19. I've spent this afternoon testing the theory. Joined up in Parallel the speakers worked fine no matter which way around the wires were. In series one way they were both noticeably quieter one way than the other so that must be the way to judge when they are wired correctly. I got the impression that in Parallel they were louder than in series but this might be because it was all done in the open. Now I am trying to carve out enough space in the J15 smokebox area to fit the small planar, an ESU 15x11mm, when I will test both setups again to try and determine which is best, and if the second speaker actually makes much difference. 

     

    Bob

  20. As there are no markings on any of these speakers and they are both of similar design, flat with sprung contacts, and able to be fitted into different sized enclosures, I guess I could assume that they are given ‘standard’ polarity I.e. the same orientation, and then go from there.

     

    Thanks for the helpful replies.

     

    Bob

    • Like 1
  21. Quite basic question I’m afraid but one I have not been able to find clear answers to with searches although I have tried. Maybe I’m a bit thick.
     

    I have a sound fitted tender loco, Hornby J15 with Zimo MX645 + Zimo 8ohm dumbo speaker, that I want to try and add a small 8ohm planar speaker into the smokebox because as it stands the sound is great, but does really seem as if it’s coming from said tender rather than the loco. I’m hoping that this might help balance it a bit better. 
     

    As I understand it the MX645 is capable of driving two 8ohm speakers in parallel (4-8ohms at 3W)  but I can’t seem to discover whether polarity is important or not I.e. if the wiring needs to be the same to both or doesn’t matter. And if it does, how to set it up, to tell what the polarities are etc. without blowing up the decoder amp!

     

    Can anybody advise please? 
     

    Thanks,

     

    Bob

  22. 1 minute ago, Pacific231G said:

    I agree with you about the Minories "eye" being the defining feature of a Minories.

     

    And I think this came about by the need to come up with a design that used just standard L/R hand points, all that were available for TT at the time. This was the driver from which it all developed IMHO. Everything past that just refined and adjusted it for other scales and needs.

     

    To my mind though it wasn't just about the track design, so simple and clever as it is, but the whole concept. A small folding layout that could be used and then packed away in a small space. Maximum usage from minimum hardware in terms of layout size, rolling stock numbers, and thus total outlay. The way housing is going these days, new builds where there are no garages and precious little other spare space of any kind, means ideas like this will become even more important than they have been in the past for many. Witness the growing number of 'shelf/plank' layouts now around. It has always been this way for me.

    • Like 6
    • Agree 1
    • Interesting/Thought-provoking 1
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