Re:New Area For Coal Powered Trains

John, here's a photo of the modified grate.
The mod was quite easy to do using a Dremel Cut-off wheel. It took all of about 10 minutes to remove the cross pieces.

By the way, our club had a two day steamup at an event called Log Cabin Days. It is a nice venue with our club's portable layout being located about 15 feet from a very nice river. My Annette performed well over a 90 minute run yesterday and today, Tom Myers Shawe converted Jack did the same for about the same time. We were all smiles.


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Looking at the state of your grate and mine, Will, I wonder how long they will last? I reckon there could be an after-market for grates for Annettes and Annabels built along the lines of DJB's. Although the Sabre Steam grate is allegedly made from stainless steel it seems to rust pretty well!
Steve
 
Paul Spann said:
Please keep on topic!
Click to expand...
I hate to be a pedant... but should that not be "coal fired locomotives"???????
 
400Parker said:
Looking at the state of your grate and mine, Will, I wonder how long they will last? I reckon there could be an after-market for grates for Annettes and Annabels built along the lines of DJB's. Although the Sabre Steam grate is allegedly made from stainless steel it seems to rust pretty well!
Steve
Click to expand...
It depends on the grade of SS used. Some SS does corrode away quickly and is intended for "ornamental" uses
and 316 would be too soft and deform under the heat 18/8 probably best for this application..... if you got really serious you could make up a pattern and have individual firebars lost wax cast.....
 
"Looking at the state of your grate and mine, Will, I wonder how long they will last? I reckon there could be an after-market for grates for Annettes and Annabels built along the lines of DJB's. Although the Sabre Steam grate is allegedly made from stainless steel it seems to rust pretty well!
Steve

It depends on the grade of SS used. Some SS does corrode away quickly and is intended for "ornamental" uses and 316 would be too soft and deform under the heat 18/8 probably best for this application..... if you got really serious you could make up a pattern and have individual firebars lost wax cast..... "

There have been several discussions about grates and patterns, but this is the first that I've seen dealing with the specifics of materials.

My question is whether anyone has thought about using Stainless Steel mesh. After only a few minutes of searching, I found a 4x4 mesh with the following specs.

The welded mesh is SS 304 [Does anyone know whether this would be suitable for our purposes?]
Weave: 4x4
Wire Diameter: .032
Distance between wires: .218
Open area: 76% [If cross members were removed, this would increase to 88%]
Cost: $10.01 per square foot

If this mesh would be suitable for the heat generated in a coal fired loco, wouldn't the fact that the members are wire [0.032 diameter] mean that the grate would be almost self cleaning? My non scientific theory is that less ash would gather on the round surface than on the flat surface presently used. It's also thinner.

Note the cost of only $10.01 per square foot. It's quite low as 1 square foot would yield at least 8 grates [$1.25 per grate for the material].

The chemical composition is on the company's site: http://wirecloth.bwire.com/viewitems/welded-wire-cloth/ss-304-welded-wire-cloth ?

Just some thoughts.

Will
 
Re Grate Mods,
Thanks to all for the information provided. Just as an after thought, looking at the photos of the grates that have been posted I was suprised at the poor condition that they are in allready. I run my locos at least once a week for an hour or two and both are almost as good as new condition. Perhaps the grade of SS used by Sabre has been changed ? When I got my Annabel I had to ask David Cooper to send me a plug to block off one of the fire tubes as the loco created to much steam. Fitting it reduced the boilers ability to create to much steam so I made one myself for Annette. Both have proved to be a worthwhile mod.
Now I have a confession to make, I have made a partial mod to Annettes fire grate by cutting off only half of the cross bars that some other members have cut. Had a Steam up this morning, 32 deg C outside, hotter inside the garage. Result..........................To much steam. Lesson..........................If it aint broke dont fix it!
John
 
Firstly to Will. Where's a physicist when you need one? It's an interesting concept and cheap to try. Why has no-one ever come up with this idea? A fine mesh may well result in the same problems that we've had with the grid type gate. Spacing the wires further apart will require them to have greater strength until we end up with wires as thick (or almost as thick) as firebars! But please give it a try. Experimentation is part of the fun of this game and although the locos are 1/19th scale (or thereabouts) the physics doesn't scale down similarly. Usually this is a problem but in this case, maybe we can use it to our advantage.
And to John. I've tried running my Annette both with all six tubes and the smaller two blanked off to give four working tubes. I've concluded that 4 just won't hack it. But I'm running outdoors on a railway with a long and stiff 3% gradient so my loco needs all the steam it can raise. I think you're very lucky to have a beautiful indoor and level railway so your operating conditions will be very different and your loco will be able to run on only a hint of steam. These locos are based on Roundhouse chassis and R/H gas fired locos will run at even 10 psi. The problem with a coal fired loco running at such a low pressure is that it's impossible to raise pressure again using the steam blower (as I'm sure you well know). Your loco won't be using as much steam for traction so you should be able to achieve a nice balance relatively easily.
On my Edrig, the way to cool things down used to be to open the firehole door but Paul Bailey (of DJB Engineering) provided me with a modified door with a damper (similar in concept to Tag Gorton's but not the same) which can control the fire. (I gather it's now a standard fitting on Edrig and Ragleth conversions).
I hasten to add, I'm still learning so the above should be read with a certain degree of sceptisim and of course if you think it's a load of bo!!ox please say so. It's the only way to learn.
To paraphrase John Boyes - "Happy coal firing"
Steve
 
When I purchased my Annette, David Cooper suggested that I plug the two small flues with 1/8" copper tubing as the boiler was "quite robust". I did what David suggested by cutting two 1/2" long pieces of 1/8" copper tubing and then crimping the end so as to block the flue. I noticed very little difference in the steaming of the loco so I removed the two plugs.

As I've stated, I have had two very strong runs of about 90 minutes since then. On this past Saturday, I had one run with 12 loaded goods wagons, including 5 loaded slate wagons [loaded with real slate] and 4 log cars [each with either 3 or 6 1.5" X 6" logs]. The heavy load made little difference in the steaming ability of the loco.

As for the grate, I'm going to search for material for use in making a grate. I'll write about the results.

Regards,

Will
 
Own Up, who bought the fire grate off E Bay with a view to a modification to their Sabre Steam Loco ? I bid but it went a bit high, £18 with £6 Postage from N.Ireland. Will wait till the Model Eng Show in October off the Fosse Way.
John.
 
I've making Coal fired locos for 10 years now, 3 locos in total, all my grates are 3.2 stainless steel rod, 3mm apart, silvered soldered to SS rod at front and back, The front rod is 55mm long and taped 8ba to fit inbetween the frames and swing down, the rear of the grate held up by a 1.6mm pin through holes in the frames, An ash pan below.

regards
Steve
 
Gordon Watson of Argyle Loco Works (on this forum as "taperpin") very kindly sent me one of his "rosebud" grates to try on my Annette. That combined with the new blast pipe he sent me has transformed the loco and it can now haul both light and heavy trains at realistic speeds. I'm going to do a longer post when I have some video to post as well, but the conclusion I've reached is that the Sabre Steam locos can be made to be quite reasonable runners, but it depends on how much work is involved. Fortunately my loco required "tweaks" of varying difficulty, whereas some of the later locos have needed a complete rebuild.
Steve
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I'm sure I recall 'LBSC' writing about grates, and specifying an ideal free air/firebar ratio, but I have no idea where I read it, and it likely was 30 years ago! There certainly is a scientific approach available, we just need to find where it is held!

I should add I don't have a G scale coal fired loco, but do have many, many years experience driving rather larger ones - 9 1/2" gauge!

Another thought - John Brittain seems to do just fine with his Garratts, I wonder what sort of grate they have for comparison? I have seen these run on 'Ttarrag Shed' for hours......impressive. Want one!
 
I've recently bought a "Blackadder" from Simon Whenmouth, virtually unused although 17 years old. Now I know what it is to run live steam in 16mm!

And so to Sabre. David C fitted his locos with four large tubes and two small ones to avoid litigation. I'm really not surprised that he said to blank off the small tubes- they could not have been much use, anyway. My no.0 has only the four tubes, anyway. There may be others....

I "modified" my grate but I overdid it. I like Argyle's "rosebud" grate, which seems much more like it. Now, I need the new, shorter, blastpipe and blower. Eventually.......

Tim
 
Tim,
The air/grate ratio is 40% or so, but the other virtue is the heat retention underneath the fire of the 4 or 5mm thick steel plate.,his helps with stability of the fire avoiding wide variations in temperature after adding fresh coal.

Gordon.
 
The thing I wondered about with the "rosebud" grate was the possibility of the holes getting blocked with ash and small coal. It seemed an open invitation. In fact there has been very little ash dropping through the grate into the ash pan, but that's not because the holes are getting blocked, but because the fire seems to be burning more efficiently. When I drop the fire there may be one or two bits of ash/clinker in a couple of the holes but nothing more than you'd find on a grate with bars. I am hugely impressed. And the best thing for anyone wanting one, is that they are easier to make than silver soldering steel bars (and probably cheaper too!). The old Sabre Steam grate was beginning to burn away so there will be many more people needing new grates soon (depending on how much they run their locos). I wonder how John Morgan's grates are doing. He runs his locos quite a bit I believe.
Steve
 
And so to finish, on my no.0. John Shawe offered to fix it, knowing what it was like. He took it away, and returned it last week.

He replaced just about everything, except the boiler and the axle pump. The boiler works fine, (being a copy of the DJB one, with four tubes, and not the Sabre six tube one), and the tubes are 1mm thick, rather than 2mm. John said that the axle pump was oversupplying, but I don't mind that, as my line is rather steeply graded, and I can always turn it to bypass for a circuit.

Also, John rebuilt the Roundhouse chassis, which now runs as Roundhouse intended it to.

The net result is a sweet, docile and very powerful steam loco.

Now I've got to get the "Annette" plates off. Any ideas?

Tim
 
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