irishthump

The paint is phoenix precision CIE golden brown you can get it in Marks Models http://www.marksmodels.com/?pid=18593

Exactly which coaches are painted in that colour, Anto?

Hi all,

 

Just joined this forum and although I don't currently model railways I have an interest in the Irish scene, and have been taken aback by the work many members here have produced.

 

At the risk of hijacking a thread and perhaps tempting a ban on my first post here (!) if you'll allow me, perhaps I can give some information on GM engines used in Irish locos which may give some insight into their unique sound.

 

The A class were re-engined with GM 12 cylinder 645E engines in the late 1960s & early 1970s. These engines were fitted with 2x superchargers (known as roots blowers). The two roots blowers were located on the generator end of the locomotive. For the observers among us you will notice the addition of the two "mushrooms" on the roof at the end of the 'air vents' to facilitate this on the rebuilt A classes.

 

The GM engine's sound is very much governed by the type of exhaust manifold fitted to them. The A class have 3x exhaust ports on the roof roughly in the middle between the "air vents". It is this which gives them the unique sound. The original exhaust port for the Crossley engines was the circular hole at the opposite end of the fan which was filled in once re-engining took place.

 

Generally 645 engines idle at 315rpm and have a maximum speed of 900/904rpm when on full power. For the A class most were limited to 800rpm owing to the electrics & generator output (although several were re-rated to 900rpm for several years before being de-rated back down to 800rpm). I would imagine this would have had something to do with traction motor cooling owing to higher voltage being through them (the motors on the A class were naturally ventilated as opposed to all other CIE/IR diesel electric locomotives which were force ventilated).

Incidentally there are still several locomotives still in existence in Eastern Europe with the same engines & exhaust manifolds, and sound virtually identical to A classes - although on full power @ 900rpm!

 

The notching on GMs is somewhat 'gradual' in terms of power. When the driver moves the throttle locomotive from say notch 1 - 2 the engine will rev up to the set RPM and then the load from the generator will increase (governed by the load regulator) and you should notice the engine revs drop slightly as the "load" increases.

On the A class the load regulators (which are Metrovick and not GM) were tweaked to put out a higher rate of voltage once notching occurs, hence less of a "wind up / wind down" sound on the engine when notching up or down. This enabled the A classes to have the ability for quicker starts from stations. The load regulators on the C classes (again Metrovick) were set-up similarly to what is in other GMs, and more of a "whine" can be heard from the engine as it winds up / winds down.

 

The 071s and Class 57s do have basically the same engines, but the 57s are more heavily silenced and have 4 (?) exhaust ports through silencers as opposed to one on an 071. The higher idle RPM on a class 57 may be down to it drawing ETH. Incidentally as far as I'm aware the 071s were fitted with different turbochargers in the early 1990s which seemed more durable than what was in them originally. If you listen to an 071 compared to a 111 there is a distinctly different engine note between the two. The 111s tend to 'whistle'... While the 071s engine note sounds a bit more "meatier"! Although, I should say that 076's engine is fitted from an ex Swedish diesel and sounds very similar to a 111.

 

Hope this may provide some sort of explanation on the unique sound of our Irish locos,

 

Regards,

 

Vlak.

Vlak, thank you for the informative post! A wealth of information there....

I wonder can I pick your brains further? DO you have any information regarding transitioning of the traction motors in the Irish GM's that used the 567 engine?

I'm guessing that transition was automatic considering the time these locos were manufactured.

A little more progress....

Got most of the station trackwork completed. Here's a short video of a rake of MK3's snaking it's way over the pointwork into what will eventually one of the station platforms.

It could be the circuit board in the loco causing a short that fried the decoder. The fact that you were able to programme an address to the decoder in the first place would indicate that the decoder was ok to begin with.

Im trying to gently get him to see the error of his ways

 

In fact you dont need both controllers powered on,( i.e. throttle advanced ) because in a standard emitter follower ( series pass) DC controller, there is a constant path to the OV line, even one controller has its throttle to zero, the other controller will be staring into a 0V line dead short.

 

fundamentally , there is no common rail in a DC system, both rails can assume both polarities ( at different times )

 

DCC is different, it will work in that case ( though its not of course necessary )

I'm glad I run DCC!

Well, nothing, other than the train on the track that is now being fed from the 'reversed' controller will go the other way, as was required.

 

All that matters to any loco is the difference between the two rails that it's on.

But if you have one controller set forward and the other set backward if both are turned on you will have a short at the common rail.

You will have to be sure to never have both controllers powered on at the same time.

By powered on I mean with the throttle above zero.

Congratulations and the best of luck with the new layout, 14x10 is a nice amount of space!

If you simply want to switch between the 2 controllers then you can just use a SPST wired to the red rail as in Broithe's diagram. Then you wire both controllers using the black wire as a common return. This won't cause a short.

I used an old Lima parcel van to make a rough approximation of a Dutch van a couple of years ago. It was just a straight respray with an added grille on each side. I think the chassis is around the right size, but the bogies are all wrong.

http://irishrailwaymodeller.com/showthread.php/77-Graham-s-Workbench

However the original Lima wheels are a bit rough. It would probably be easy enough to buy the correct bogies and scratchbuild a chassis.

Got the track for the main loop laid over the last week. It's all Peco flex track with Peco streamline points (won't touch Hornby ones again!) I fixed the track down with No Nails (clear variety) and I'd highly recommend for laying track. It holds the track down without the need for any pins, even on curves. By the way the points are all insulfrog, I used them on my last layout and never had any stalling issues with them at all.

Anyway here's a short video of me testing out the loop.....

Irony of ironies, they might be perfectly happy to see spot-on Irish rtr models with every rivet accounted for and then go run them on 00 track.

With a dirty great Hornby tension-lock coupler sticking out of each end!

People can choose to buy them or leave them. It's a free country last time I looked.

What's really funny is that some people are getting more worked up about the fact that some people don't care about the inaccuracies rather than the innacuracies themselves!

I checked up on those sound files, and although the sounds were reasonable, the sound programme was pants, with only 2 notches, and very little else. As I said earlier, file 74460 is much more comprehensive with 8 notches, even though the sound is not quite right, but I am working on that. As you say, the A class just don't sound like the other GMs.

I had another listen to 74460, and it appears I was thinking of a different file altogether! It actually does sound quite good.

Hi Eamon,

The design depends on what the most common donor motive power will be based on.

 

hacked Hornby class 33 new version

pancake motor

athearn jobbie

tenshodo

etc....

It would be pretty hard to come up with a "one-size-fits-all" solution I would think.

I agree that the sound is not right for the A Class, but it is better than nothing for the time being. I certainly would not buy a decoder with that sound on it.

I am experimenting with copying each individual sound file and running it through a Graphic Equaliser to change the sound of it, then rebuilding the sound programme. Have had limited success so far, but it is a time consuming task, and not high on my list of priorities at the moment.

I look forward to hearing any results you come up with. And that's the beauty of having the Lokprogrammer; you can chop and change to your heart's content! And in the end the sound only really has to make YOU happy.

Drifting slightly off, but having watched many hours of DVDs on Irish railways to jog my memories of GM and MV loco sounds, I could not help but notice A class locos sounded rather tame and nondescript compared to the evocative and distinctive sound of the baby GMs notching up and down.

That's what I was thinking. The notching seemed much more gradual, maybe the throttle arrangement is different on the A class.

I checked up on those sound files, and although the sounds were reasonable, the sound programme was pants, with only 2 notches, and very little else. As I said earlier, file 74460 is much more comprehensive with 8 notches, even though the sound is not quite right, but I am working on that. As you say, the A class just don't sound like the other GMs.

I didn't realise they were so limited notch-wise, I only listened to the files using the virtual throttle on the Lokprogrammer software. But like you say the sounds aren't too bad.

I just think 74460 just sounds completely wrong for the A class.

Are you thinking of modifying the sound file?

Not sure yet IT. I am working my way through the ESU library looking for something that sounds remotely like an 001 class, and then add horns recorded at Downpatrick. Have you any suggestions?

I've spent some time looking too, to me the A class didn't really sound like the other EMD locos. There are 2 files that I could find that have Sulzer prime movers that I think are in the ballpark anyway. Try files no: 56451 and 54457.

Yes, the chassis is live, but as long as none of the electrics is making contact with it there is no problem.

Gotcha. What sound decoder are you planning on using?

One question; I assume since it's basically an Athearn design that the chassis is live?

Fantastic job!

I myself tried to fit Athearn CoCo bogies to an F7 chassis a while back, but just couldn't make it work. This is an excellent solution, I'd love to see a video of the completed project.

A little more progress.....

I've spent the last few days hand painting lengths of flex track and most of the points. I decided to hand paint the rails before laying the track as I didn't fancy spraying all the track with my airbrush in the confined space of the attic with no ventilation!

With the track plan pretty much finalised I went ahead and fixed down the trackbed. I used Woodlands Scenic foam trackbed partly because it seems very easy to work with and it also worked out cheaper than cork. I fixed it down with "No Nail" adhesive.

Here's what will eventually be the main terminus:

The two tracks on the left will be the terminus platforms and will be mostly covered by the station building. (I'm going to have to figure how to deal with that ugly wooden beam on the left! I'll have to either hide it or make a feature of it.....) The longest train that can be accommodated is 5 markIII's with a 201. That's shorter than I would like but I can live with it. The two tracks to the right are for freight and coach storage. I've placed a point to show where I'll be putting a loop which will allow an engine to run around it's train and will provide access to the freight/container yard.

Here's another pic looking towards the entrance to the station yard:

You can see how the track on the far right leads out of the station yard and around to the right which will allow access to the engine shed or to link with the main double track loop.

Here's the mail line and on the left is where the engine shed will be placed, pretty much where that Peco shed is standing. There's no underlay here, I plan to lay the engine shed tracks directly onto the baseboards to have a little height difference from the main.

Here's a shot of the removable section:

Hopefully I'll get some of the main line laid before the weekend.....

One thing i love about a garden layout is the lighting.

 

 

I think i will have to get me some weathering powders and sealer's and try weather the building a bit.

I don't think there's any need. "The Weather" will do all your weathering for you!

- and they do post to Ireland if you contact them.

That was a joke!

I would've had a punt on this, but the seller doesn't post to Ireland....