# Accucraft SP Mogul mods



## Dr. J (Feb 29, 2008)

I'm contemplating purchasing an Accucraft SP mogul and making some cosmetic changes to more closely resemble a B&M Mogul. The SP seems to have compound cylinders (or a cylindrical steam chest?), whereas the B&M has a single cylinder with a squarish steam chest on top. I'd appreciate any advice on (a) How to get the SP cylinder/steam chest assembly off (preferably without having to fiddle with the running gear), (b) advice on how to rework the SP unit to resemble the B&M. I found an article on-line about tearing down an Accucraft cab forward, which was a bit overwhelming (Google search "Accucraft Cab Forward (AC-11/12) Disassembly Manual"), although it did give some indication of the overall design of the cylinder and steam chest, and the cosmetic shell that overlays the working parts. I'm wondering if there's anything like "Dismantling your expensive new toy for Dummies"? I also plan to take the plunge into getting a miniature mill and lathe, and I'm hoping to be able to either modify the existing components or build a new lower cylinder. Once again, any advice is welcome. (By the way: The photo of the SP mogul is from the Glacier Park O scale mogul documentation. It's an M6, like the accucraft offering).










We'll talk about the vandy tender another day.


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## David Leech (Dec 9, 2008)

Dr J, 
The pictures show the different look of a 'PISTON VALVE' loco (the SP) and a 'SLIDE VALVE', also called a 'D' valve (the B&M). 
I am not familiar with the Accucraft model (since it won't be out until October of this year), but on the model, underneath the rounded top part of the cylinder casing, you should find the flat top of the valve chest, similar to, but not identical, to the B&M. 
It will look a little wider and lower, I would think. 
It should be no major job to make it look similar. 
All the best, 
David Leech, Delta, Canada


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## craig0127 (May 20, 2008)

I had thought about this same mod but it had looked too out of range for me . Larger drivers would be in order too . Love to see a ten wheeler in b&m style from acc or roundhouse.


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## David Leech (Dec 9, 2008)

Craig, 
From what I can find on the internet, both the B&M and the SP moguls had 63" wheels. 
Is that not correct? 
Regards, 
David Leech, Delta, Canada


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## craig0127 (May 20, 2008)

Disregard last message ,wrong mogul. . Probs with iPad too.


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## craig0127 (May 20, 2008)

David . Absolutely thought the conversion was from the old wood burner from acc.


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## rwjenkins (Jan 2, 2008)

Although the B&M moguls were built with slide valves, they were actually retrofitted with piston valves at some point in their careers. You can see the round valve cylinder cover on the front of the square steam chest. These were bolt-on replacements for the original slide valve chests.


Apart from the lower-mounted boiler, and the obvious difference in tender style, it seems like the same engineering that goes into the SP mogul could be applied to the B&M model. I imagine if enough of us were interested, Accucraft might be convinced to produce a run of them? If so, count me in for one!


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## Dr. J (Feb 29, 2008)

Thanks to all, for your comments. I had noticed the circular end-plate on the steam chest. Now I understand. SP went from D-slide valves to piston valves. Not a compound cylinder. 

I've attached a clip from the Cab Forward teardown article (I couldnt see who wrote it; no name in the PDF, but thank you, whoever you are). One easy thing I could do would be to fabricate a new upper lid to the D-valve assembly, to give it some overhang. Or, just soft-solder brass strip around the front & sides. Then, fabricate out of round stock a fake lower cyl that would slip over the bottom of the existing cyl. Or maybe make new end caps with a larger diameter, and cover then with brass sheet. Either way to bulk up the lower cyl, relative to the rectangular profile of the steam chest. The hardest part (as with real surgery) is going to be gaining the exposure. I would like to avoid removing the boiler or meddling with the side rods, quartering, etc.

Do you really think we could get ACC to make a run of these, with the right tender?
A nice, generic, turn of the century Baldwin Mogul, or 10-wheeler, or even a circa 1920s USRA consolitation. Some nice, "Eastern" day-to-day workhorse that would like right poking around branch lines.










Dr. J


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## Charles (Jan 2, 2008)

Posted By Dr. J on 01 May 2012 05:21 AM 
Thanks to all, for your comments. I had noticed the circular end-plate on the steam chest. Now I understand. SP went from D-slide valves to piston valves. Not a compound cylinder. 

I've attached a clip from the Cab Forward teardown article (I couldnt see who wrote it; no name in the PDF, but thank you, whoever you are). One easy thing I could do would be to fabricate a new upper lid to the D-valve assembly, to give it some overhang. Or, just soft-solder brass strip around the front & sides. Then, fabricate out of round stock a fake lower cyl that would slip over the bottom of the existing cyl. Or maybe make new end caps with a larger diameter, and cover then with brass sheet. Either way to bulk up the lower cyl, relative to the rectangular profile of the steam chest. The hardest part (as with real surgery) is going to be gaining the exposure. I would like to avoid removing the boiler or meddling with the side rods, quartering, etc.

Do you really think we could get ACC to make a run of these, with the right tender?
A nice, generic, turn of the century Baldwin Mogul, or 10-wheeler, or even a circa 1920s USRA consolitation. Some nice, "Eastern" day-to-day workhorse that would like right poking around branch lines.










Dr. J


Dr. J
The work you reference is a manual presented by Triple R services. Good luck with your project.


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## Pete Thornton (Jan 2, 2008)

just soft-solder brass strip around the front & sides. Then, fabricate out of round stock a fake lower cyl that would slip over the bottom of the existing cyl. Or maybe make new end caps with a larger diameter, and cover then with brass sheet 
My suggestion was on those lines. Leave the mechanics alone, unless you have practice tearing down a live steamer. Just make cosmetic covers for the existing cylinders and valve chests.


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## rwjenkins (Jan 2, 2008)

Posted By Dr. J on 01 May 2012 05:21 AM 
Do you really think we could get ACC to make a run of these, with the right tender?

I'm sure they would, if there were enough confirmed orders. Keep in mind the Accucraft Mason Bogies started out with a bunch of people getting together right here in the MLS Live Steam forum and saying "hey, let's get Accucraft to build us an engine!" so if there's enough interest, there's no reason why it couldn't work for the B&M mogul. The person to talk to would be Cliff at Accucraft, he could tell you how many orders would qualify as "enough" and the likely cost per unit. I imagine drawings of the locomotive would be available from the B&M Historical Society, or from the Danbury Railroad Museum (where the 1455 currently resides), and in theory they could even help to bring in some orders by putting flyers out at the museum or an ad in their newsletter.


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## David Leech (Dec 9, 2008)

IF you have the money, then I am sure that Accucraft will be glad to make you 50 - 100 units. 
My own opinion would be that it is unlikely that Accucraft will do it on their own, given that they seem to have a lot of stock still for sale. 
But you never know. 
Also, if you have all the model engineering drawings done now, I bet that it will be 3 - 5 years before the production locos appear on your doorstep. 
But again, maybe it will be quicker. 
If you want just one for yourself, find a capable model engineer to make you one to your own requirements. 
All the best, 
David Leech, Delta, Canada


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## rwjenkins (Jan 2, 2008)

The nice thing about the B&M mogul is it wouldn't have to be mechanically any different from the SP version (except for the lower-mounted boiler), vs. coming at them with a completely new project. The big question is, how much appeal would it have beyond New England? And how many of the New England live steam guys would buy one, considering that most of us know each other and we would all be showing up at steamups with the exact same model?


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## Reg Stocking (Sep 29, 2010)

Why should a B&M Mogul have a really restricted appeal? There are times I wonder about Accucraft's choices of prototypes, e.g. the SP narrow gauge ten-wheelers, but apparently there are enough fans to make the model run worthwhile. I'm not a B&M fan, but at least there would be another variety of engine to look at. And it wouldn't be a case of starting from scratch, which should make it far less hassle and expense.


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## Dr. J (Feb 29, 2008)

Thanks again, gents
Since I've been looking for an excuse to buy a miniature mill, I think I'll have a go at this project myself. 
But I do wish Accucraft or Aster would do a "modern" (i.e. 20th century) Baldwin mogul, 4-6-0, or a generic USRA consolidation. 
Jim C


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## Phippsburg Eric (Jan 10, 2008)

Being and Easterner born and raised, It doesn't feel right that the UP, DRG, SP all seen so well represented when only a couple eastern railways are represented and only with the most famous engines. I guess most of the small scale live steamers are out west and those are what they see when they go to look at operating steam. 

I have ranted on about having some smaller engines to chose from as well, the Mogul is that for which I am grateful, Jim will have a good running and nice looking locomotive when he is done!


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## Dr. J (Feb 29, 2008)

The Vanderbilt tender fairly screams "SP." Right now, I am planning to build my own box type tender, but it seems a shame to sacrifice that nice vandy tender, or leave it gathering dust. So here's the question: How many of you would be interested in buying this locomotive if it came with a box type tender? Or, more broadly, how much of a market is there for a box type tender as an alternative to the Vandy tender? I think the AML 0-6-0 (in 1:29) offers the option of either style tender. If ACC can make money on the deal, I suspect they could be persuaded to run a batch of box-type tenders that would be compatible with the SP Mogul. It would be win-win, becuase (if my hunch is correct), they could sell not just tenders, but more Mogul-Tender combinations. Let me know. If there's enough interest, maybe we can get "half a loaf" from ACC, even if they dont run a different locomotive for us Eastern guys.
Jim C


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## Pete Thornton (Jan 2, 2008)

if there were enough confirmed orders 
Bear in mind that Accucraft isn't the only shop in town [China in this case.] The UK guys are having fun getting locos built by Accucraft and WuHu, and there are two or three other shops that claim to be able to do it. Almost any engineering shop will ask for a fee for the prototype and a guaranteed number of copies - it usually makes economic sense at 20 or 30 units. Accucraft seemed to prefer a guarantee of 50, but that may have changed since the FWRR. 

You only have to order the 20-30 units and send the money. Who you sell them to is up to you. WuHu recently finished a 2-8-0 in 1/32nd scale which is pretty close to the basic engine you are looking for?


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