Simond

Chaz

Please do let us in on your painting & weathering techniques - buffers & coupling - powders or drybrush, or ...?

And, how would you have glazed the duckets ? (I'm curious, but as my theme is GW, no more than that!)

Thx

Simon

11

Alan

Thanks for your thoughts.

I shall use a computer PSU at least as an experiment. I'm certainly not going to open it up, so that's not a concern (any more than I'd be worried about having a valve guitar amp or an old-fashioned CRT TV), but the zero volt thing is an interesting point - probably not an issue for point & signal control, or lighting, but probably well worth avoiding for track where multiple feeds are envisaged - and where human contact might be expected to be the norm, eg for track cleaning. Shouldn't be a single point of failure risk, but could make another failure worse, perhaps.

Thanks again

Simon

Alan

This thread

http://www.rmweb.co.uk/community/index.php?/topic/9726-using-an-atx-computer-power-supply/

Best

Simon

Hi all

Thinking of the day when I will need a power supply to run signal & points servos, a desktop ATX power supply seems like a useful option.

http://en.wikipedia.org/wiki/Power_supply_unit_(computer)

Prices from about £13 for 500W, which should be enough... (Though this is split between 3.3, 5 & 12V, all of which are regulated and over-current protected)

Anyone tried it?

(A check on the search did lead to a thread from 2010 largely promising death & calamity to anyone who even considered it - I was hoping for a less sensational response)

Best

Simon

Ozzy

I think you might have difficulty turning a loco with 64' wheelbase on a 65' table - I'd need to draw it to check, but I can imagine that the flanges might not quite clear the railhead of the fixed rails - it would certainly be close - in any case, you'd need an unnatural precision in parking the thing.

I also suspect that the balance might be a bit important if you're pushing it round by hand, but I've never done it, myself.

Best

Simon

I built one. I would say that following the instructions you'll get what you bought - if I were to do it again, I'd spend more time planning - mine was a GWR one and I am sure I could have improved the looks and detail if I'd spent more time thinking (and looking at pictures) before diving in - particularly a foundation for the ring rail above the pit bottom.

No major criticisms of the kit apart from the tedium of cutting endless riveted brass angles to fit the "panels" on the girder sides - it would have been hugely better if each of these had been an etched "entity" rather than 4 different lengths of etched angle riveted individually. I suspect that this may not add (much) to the etching costs of the kit, and would certainly improve the build-ability, and maybe the appearance of the finished article.

Given that there were some blank bits of the etches, it might have been nice to have a few notice boards, or something equally useful, but this is being over-picky perhaps, and the details of the locking gear are a bit sparse.

Pre-plan if you want a DCC version (supply rails from spindle and ring-rail with polarity controlled by relay or reverse loop module) or DC (supply from split ring rail) otherwise risk of shorts and no sound.

Lots of photos and stuff about stepper motors on JeffP's thread.

Best

Simon

Eric

I have not yet had a chance to try your code.

I am interested by your pi-server approach and JMRI but have a) no experience of it, b) no time and c) no need at the moment!

My tendency would be to have signalling separate from driving, but there is clearly an option to have an automated fiddle yard - I think there was a Peter Denny article in RM, years ago entitled "An automated Crispin" in which some bells and whistles and some clever woodwork replaced his son in the operation of his FY, so the concept is not new, but certainly interesting.

Do, please keep going, and keep the posts coming.

Controversially, lots lower than the high one, but a bit higher than the low one...

Sorry!

Simon

Anthony

If you make it "high" you can always make it lower...

Probably better to make a final decision before the painting, if only to preserve family harmony, but I guess this would drive you to making it removable for painting, and this will bring its own problems, perhaps.

Best

Simon

I do wish IKB had managed to build his mooted terminus at Porth Dinllaen - a competitor to Holyhead for the Irish mails.

I went to the Euromilitaire show in Folkestone for the first time last October - much of what these military modellers do is diorama - mostly not moving - and as I am sure you know, there is some utterly outstanding modelling.

They manage to show them off quite effectively, but perhaps the sheer number of models on show meant it was easier to do this than a typical railway show - it seemed to me that the Euromilitaire and the Folkestone club exhibition had attracted similar numbers of punters.

I think that my personal vote is for seeing the wheels turn however!

Best

Simon

Kev, David, Robin,

Thanks for the thoughts & suggestions

Not much happening in the signalling domain on the SD workbench at the moment - turntable on edge whilst the Arduino pro mini gets sorted, but the 28xx is finally green following the pleasant weather of the last few weeks. ( Halfords mixed up Land Rover deep bronze green in a rattle can for £14 - very happy). So I'm getting it built up again, which means the bench is a tip... Too many jobs on the go at once.

Need to finish the King, put a chip in the Fowler, send my Lenz kit in for a s/w upgrade, and build a 1361 ST, as well as finish the turntable!!!

More soon, but don't hold your breath!

Simon

It may well have been but the article I saw was by Martyn Welch and was in MRJ. Like him I used 4mm screw couplings, but these are non-working representations - that is they don't have a tightening screw, but merely look the part (and would function as couplings).

 

 

You can just make out the tensioners (easiest on the nearest chain to the camera). I have some 7mm screw couplings that do actually work but they are rather oversized for the chaining job. I'm not aware of any working ones in 4mm.

Chaz,

I just found the article to which I referred, by chance (pile of Gazettes in "small office") - the tensioners were from CPL, and the article was by Raymond Walley. Gazette volume 17, number 12, pp 26, 27.

Looks like Graham & Raymond already got there!

Best

Simon

It may well have been but the article I saw was by Martyn Welch and was in MRJ. Like him I used 4mm screw couplings, but these are non-working representations - that is they don't have a tightening screw, but merely look the part (and would function as couplings).

 

 

You can just make out the tensioners (easiest on the nearest chain to the camera). I have some 7mm screw couplings that do actually work but they are rather oversized for the chaining job. I'm not aware of any working ones in 4mm.

Chaz,

I just found the article to which I referred, by chance (pile of Gazettes in "small office") - the tensioners were from CPL, and the article was by Raymond Walley. Gazette volume 17, number 12, pp 26, 27.

Best

Simon

Robin

Thx for this. Looks like you beat me to it!

As I said, I eventually got to go out for a beer with my pals, and we discussed interlocking. Effectively, a given lever operates something, and prior to so doing it is either released by none, or one, or more other levers, and when pulled, it may release or lock other levers. Levers can also be locked by the block.

Normally, due to the way the tappets / sliders work the operation of one lever would lock the lever that released it.

The GW tables that I've looked at over the last few days show the lever number, its name / descriptor, a list of "released by" levers, and a list of levers that it "locks".

Furthermore, it is also possible that when a route is set, and the starter is pulled, it "backlocks" the route so that the route cannot be cleared until the train has cleared the block.

There are many contributors to RMWeb who can write with more authority than I on this! I haven't read the RM article though I did see last month's.

I think your "setlockrequirements" is doing what I have described above - you have described "onreq" & "offreq" which are similar to the "locks" and "released by", but I suspect that they are not exactly the same - I shall give this some thought!

I had in mind to create an excel table as described above - I think this can then be read into the Arduino code, though I'm not yet sure how. I then wanted to have each lever connected logically to a function loop, which would then verify the locking table and if allowed, act accordingly.

The question you raise about showing locked levers has also been on my mind. The red led is a good solution, and I do like the "flashing, flashing faster" approach, but it seems to me that it requires an extra Arduino pin per lever - I wondered if it's possible to use the connection to the switch to do both the lever input, and the led output, I guess the Arduino can swap between input & output modes as needed. I also thought about using buttons and LEDs to indicate the "virtual" lever position and locking state, but this seems to me to be moving away from the representative nature of a row of switches - I guess a case of horses for courses / rule 1.

It's all good fun - I'll have a play at some point, but I'm trying to get the turntable finished, so I have some space on the workbench!

Best

Simon

Me too!!

Simon

I recall an article where the author used 4mm screw couplings as tensioners for a container on a flat wagon - might have been Derek Mundy - probably GOG Gazette.

Best

Simon

Hi Chaz

Wouldn't want to suggest that you should change something you'd done, more of a "maybe, next time..."!

Cheers

Simon

Oh yes, and 18.2....

Simon

Alan

I'm sitting in a hotel in Poland (work trip), dining alone, and have been delighted and amazed by your project as I ate my goose, polenta and horseradish sauce (actually rather better than it sounds!!!) and sipped my Zywiec.

I think the work you have done on the laser cutting is just fabulous, particularly because your research and detailed prep has started to bear beautiful fruit, using quite novel techniques, it's really, really good. The interlocking crane track support pillars - yeah! The window frames, and workbench are also marvellous - looking forward to the next instalments. I hope that someone sets up a hackerspace in the Folkestone area, as laser cutting seems to offer so much potential, but the drive to Brighton...

The magnetic traverser - just super - I do think angled magnets and a wider carriage below than above (actually, angling the magnets might not be worth the effort - but the wider spacing, I think, should be) will help. The carriage will move until friction exceeds the horizontal force so having a little offset will tend to improve the accuracy of the location of the upper carriage with respect to the lower, I think. If you eventually find that it doesn't work as well as you need to ensure the accurate alignment of tracks, the other option would be to cut a narrow slot, preferably hidden from view behind a rail, or the pit wall, and have a thin "leg" between the upper & lower carriages. Hope you don't have to, but potential fall back if needed.

I'm thoroughly enjoying learning with Arduino and I'm sure your lead screw will work really well, you can program the stepper to start and stop gently, which may help your concern over alignment. As an aside, I think I just killed my Pololu a4899 by unplugging the motor whilst powered up - painful learning point to the tune of 15 quid there! - and I hesitate to mention in view of the rather different state of play, I'm working towards a hypothetical GW terminus at Porth Dinllaen - it's very much theory and planning at the moment, and likely to remain so for a year or two, but the Cambrian /GW theme is there! Please browse my threads which you'll find in my signature below.

Kind regards ( and keep the posts and photos coming!)

Simon

Hi all

As an alternative to the Peco, Switchpilot, MERG and GF servo controllers, I & many others have been playing with Arduinos.

There is a thread "Arduino Applications & Programs" containing some servo control programs for signals, points, and stepper approach to turntables - link in my signature below. The Arduino approach is certainly cheap and very flexible, but does require some programming.

Hope this helps

Simon

Golly, Leigh, I'm flattered. I will have an industrial saddle tank running - probably an Ixion Hudswell Clarke which is ready to go. A last ditch effort tomorrow morning might see my Peckett 0-4-0ST ready for action. It let me down (prima donna!) at Warley and was subbed at the last minute by my J52. I have a problem with its plunger pickups - might be a quick job.

 

I too am looking forward to seeing Pempoul again - a quite superb model.

 

Apropos the chains on the bogie bolster - the easiest way to tighten the chains might be to overlap a link or two and lock them with CA - that might not be too obvious. I don't have time tomorrow but I will investigate later.

 

Chaz

Chaz

I think you could tension the chains with a turn or two of fuse wire twisted like a champagne cork retainer. I guess you could somehow hide it, but I am conscious of your comment about the chains taking the paint off the corners of he load.

Still hoping to get a chance to see DG....

Simon

Anthony

Rest assured, it's not boring!!!

It really, really, isn't!

Kind regards

Simon

I remain staggered by the sheer scope of the thing - it is truly magnificent!

Simon