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HO Scale "Big Bad John" B-D-B+B-D-B Bipolar Diesel Boxcab

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Posted by ATSFGuy on Wednesday, December 27, 2017 8:26 PM

If you can, try to get someone who knows about eletronics to help you rewire the decoders and motors so your boxcab locomotive runs smoothly.

I wouldn't do that yourself, have someone help you just to be safe.

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Posted by NWP SWP on Wednesday, December 27, 2017 12:41 PM

Mheetu, the top one looks great let me send it to the 3d printer to see if it's good enough for him...

Steve

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Posted by Mheetu on Wednesday, December 27, 2017 12:33 PM

Not sure if this would help

 

 

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Posted by NWP SWP on Wednesday, December 27, 2017 12:17 AM

The section of track that is troublesome is where the mainline makes a U turn at the end of a peninsula across onto a shelf...

Also I found someone to 3d print the side frames but I need a scale drawing with measurements of the trucks, if anyone has or knows where to find them I'd appreciate it, thanks...

Steve

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Posted by Mheetu on Tuesday, December 26, 2017 11:19 PM

From my experience with the mth ho bi polar it will do 18inch radius.  This is due to fact that the front pilot truck got swivel from the power truck.  The power trucks also is allow to swing are little. The body on the mth model is also three pieces with the cabs attach to each end allow to swing left or right depending on the turn.  

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Posted by tstage on Tuesday, December 26, 2017 11:15 PM

What "area" are you referring to?  A yard entrance?  And when you say your T1 derails: Do you mean the drivers derail...or only the front trucks?

The T1 is long and rigid.  I think the manufacture's "recommended minimum radius" of 22" is wishful thinking on their part.  However, I suspect that there are a combination of issues going on between the layout and your T1.

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Posted by NWP SWP on Tuesday, December 26, 2017 10:55 PM

It does derail elsewhere on the layout especially when running at speed... but the area is a derailment prone area and is soon to be the target of a realignment project...

Steve

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Posted by tstage on Tuesday, December 26, 2017 10:51 PM

No, I'm sure he meant R29".  Not much of anything other than the shortest of switchers would even make it through a curve <R15" in HO.  6-axle locomotives need at least R24".

"...my T-1 derails every time I run through there".  Do you mean that your T1 derails only at a particular spot on the club layout?  Or, does it happen all over it?

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Posted by NWP SWP on Tuesday, December 26, 2017 10:03 PM

Well I went to the club and asked Casey the minimum radius of the layout he said that it is 29" radius at its tightest spot and the rest of the layout is about 30" or greater... Now this left me perplexed because that would give a diameter of 58" and my T-1 derails every time I run through there and it's rated for 22" minimum??? Could he have meant 14.5" radius? But that doesn't make sense because most motive power is 6 axle power, so maybe it is indeed 29" radius...

Steve

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Posted by NWP SWP on Tuesday, December 26, 2017 3:12 PM

Tstage, I agree R22 is stressing the bounds of reality a bit but I never said that it be the typical curviture used I would just like to have that "buffer" between operating radius and minimum before the locomotive jumps the rails, especially in yards...

I now have about 70 bucks saved from Christmas and should have more come my birthday in a month and then of course my seeking meaningful employment upon reaching the age of 17...

Funding is slowly getting better and this project should really pick up steam soon!

Steve

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Posted by tstage on Monday, December 25, 2017 11:39 PM

I think R22" will be VERY ambitious.  (My MTH 20th Century Limited cars are rated at R24".)  For sure it won't look pretty doing it.  I do think it would be a good idea to find out what the minimum radii is at your club layout.

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Posted by NWP SWP on Monday, December 25, 2017 10:11 PM

That's when some clever engineering on my part comes in...

First the two Trainmaster boxes that run half the length of the unit act as span bolsters and house two motors each which power two Athearn B trucks each two of the B trucks one from each motor share common D truck sideframes the D trucks (or two B trucks) can both swivel and slide side to side, then the B leading and trailing trucks also swivel and pivot... then each B-D-B set is joined by another span bolster to which the body is attached to... then the decoders speakers weights and anything else needed for a model... I hope to be able to "possibly" (and I use the term very loosely) shoe horn it through 22" radius curves??? But that's minimum radius not planned radius... I am going to the club tomorrow and I will ask the minimum radius used there...

Steve

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Posted by tstage on Monday, December 25, 2017 9:27 PM

Do you know what the minimum radii will be for this behemoth?  Are you going to be able to run it anywhere - e.g. on your club layout?  Or, will this just be a shelf queen?

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Posted by NWP SWP on Monday, December 25, 2017 8:43 PM

Suppose theoretically, that four Alco 251s could fit side by side and end to end each with two generators on each engine, could that work?

Steve

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Posted by NWP SWP on Monday, December 25, 2017 7:49 PM

Here's a rough draft of what formats I have to choose from, the first is like the NYC electrics, the second is is my A-B-B-A idea, and the third is full length body...

Steve

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Posted by NWP SWP on Sunday, December 24, 2017 3:51 PM

Overmod, sounds like you would be a great help with this project... So what sort of Prime Mover would you suggest? The control gear thing has me confused a bit... it will be MU capable, and I might add pantographs on it for extra power... please keep giving suggestions and advice... thanks!

Steve

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Posted by Overmod on Sunday, December 24, 2017 12:38 PM

Ah, but you have to look at the equalization and pivot arrangements on the T-motors to see why the carbody was arranged that way...

Two 2400hp 251s in a locomotive that size?  Wasn't adequate for the UP steam turbine and would not be later.  There's a reason all the electric-locomotive developments to speak of after about 1951 were diesel-truck based, even on roads that had very recently built giant locomotives with D truck underframes...

You do not want 'bad' in your locomotive to be something other than a cultural reference.  Since this is diesel hp-limited I encourage you to shoot the moon on nominal generator-output hp, far more than a couple of piddly RSDs with all their advantages would otherwise give you.

Who's designing the control gear for this locomotive?  The MU arrangements?  The dual-power capability?  We need to have more fun and less kludging here!

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Posted by tstage on Sunday, December 24, 2017 12:32 PM

What about tools (saw blades, x-acto knives, files, etc) and supplies (styrene sheeting)?  Will you be able to use the existing motor couplings to kluge the drive train together?  Or, will they all be separate?  Will it be DC or DCC?  If the latter, how many decoders will it require?  And don't forget S&H for any online ordered parts...

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Posted by NWP SWP on Sunday, December 24, 2017 12:24 PM

Athearn shells for PBs can be had for under 10 the Trainmasters can be had for about 15, and the Athearn  trucks can be found for about 30 so all in all the per unit cost shouldn't be more than 200 right?

Steve

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Posted by tstage on Sunday, December 24, 2017 12:17 PM

Have you calculated the cost of what you are envisioning?  Sounds to me like it's going to be way more expensive for the chassis, shells, and parts than settling for an actual prototype bipolar diesel.

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Posted by NWP SWP on Sunday, December 24, 2017 11:49 AM

My scheme would be that two Bipolars caught fire ruining the body luckily the traction motors and frame survived, the MILW decided to scrap the units as rebuild costs would be far to great... luckily the NWP-SWP "Super Power" division caught these before the scrapper did, having purchased running gear it was time to build a locomotive, they took two Alco PBs fitted them on a common frame then removed the idler axle from the pilots on the Bipolar frame, then they added another pair of B trucks un between the Ds then fabricated a beefier frame that two Bs and a D truck were mounted to creating half the frame, then the PBs were remotored with a power plant out of two RSD-15s which were ordered from Alco, they then were given a simple cab and were then mounted on the half frames.... How's that for an explanation?

Now if I build an A-B-B-A set the B units can be the "tenders" not having cabs and their bodies running the length of the unit...

The units will be in heavy freight service, right now depending on if I go with the A-B-B-A set the A units will have a single cab, If I decide to do stand alone units I'll make it double ended, I'm planning on 2 to 4 units, they will be painted in a livery similar to the ERIE green livery, they will be in system wide service specifically on the 2-4% grades on the several passes on the line...

Also just to add the NYC T motors had a similar porch as the Ps but had all axles powered...

Steve

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Posted by ATSFGuy on Sunday, December 24, 2017 11:41 AM

Geez Stephen, you sure like to fantasize! How many fictional locomotives does your railroad need? :)

Were these units going to be used between Seattle and Chicago? Or Portland to Los Angeles?  What was the CEO's decision behind these units, do you pull really long freight trains on your layout? 

How many units do you plan on making? I'd love to see your kitbashiing skills, but keep in mind if you want like 15 to 20 of these massive locomotives, it will get very expensive very quickly.

Do you know how to cut open a locomotive and convert it into something else?

Will the units have a cab on both ends or just one end?

And what colors would the units be painted?

I look forward to hearing from you.

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Posted by Overmod on Sunday, December 24, 2017 11:26 AM

I recommend MUCH more detail 'inagineering' before actually finding donor engines and cutting metal/plastic.

First order of business: you're more or less assuming reuse of bipolar Batchelder drive -- if not, what changes to the older chassis will you need to make for new traction motors or shafting?  Not much later (by WWI for sure) there were electrics with similar light built-up frames and twin motor quill drives, far more 'useful' for traction but more difficult to package internal-combustion motors and fuel into...

Then we have the prime mover choice itself, either large medium-speed or relatively smaller multiple engines.  A modernized version of the Essl Baldwin is very likely your best bet,  and you should read up on that locomotive's history and detail design for options, particularly carbody (the 'modules' included sectional radiators and carbody sections).  A repower in the 1950s with Maybach Diesel-hydraulic transmissions, or the Bowes drive from the Kaiser 2000hp passenger unit, might be an interesting historical option (suffering from some of the common-mode issues the Krauss-Maffei Amerika-Loks would have in the '60s).  Note that the chief problem with the Essl design, excessive cost to manufacture, would not apply to you ... so you have plausible denial for such a large repower, and you can quote the relative advantages for the Centipede design in Kiefer's 1947 motive power report.

You will be reinventing the problem rhat killed the PRR V1 turbine if you do not provide serious fuel bunkerage - enough for several divisions' range.  As on Baldwins all this has to reside above belt level, must not slosh, and any leaks or spills have to be kept scrupulously away from getting into the wiring, including ground returns and reference, or affecting other hoses and plumbing.  This represents variable weight, a higher and variable CG, and at least possible issues with slosh at speed (remember the SDP40F water fiasco?)

Now for more fun: even with equalization you want to make some optimization of weight distribution over the powered axles.  The porch on a P-motor presupposes two-axle idle lead truck and minimal equipment needing to be packaged in the carbody.  I would be tempted to see if a body structure articulated with each truck could be used, as you then have no complex pivots or weight transfer slides over the 'existing' chassis, which may take all the buff/draft forces entirely through the truck arrangement instead of a carbody frame.  (In a model this greatly simplifies how your motors or shafting would run, and how to keep adequate flexibility for traction high and nonprototypical overhang on curves low).

While you will not have to do tedioud cross-section weight analysis for balance (as Baldwin would in locomotive design) you will still want a ballpark estimate of weight on each driver pair, and shuffle the mechanical design, perhaps to give an approximation of tapered loading.  This in turn will have strong impact on your carbody and subframe arrangement.

I would be remiss if I didn't mention adaptive reuse of other locomotive components from around the general historical time of this repower.  The UP second coal turbine used a whole war-weary PA for auxiliary power; EMD F nosed were appended to the one Z-motor PRR didn't re-use; one of the expensive Alco Shark repowers hung around into the '90s ... there would have been a wide range of unfruitful first-generation power 'around' to contribute cheap carbody and other parts.  (Personally I'd recommend adapting RF-16s for full carbody, transverse-engine mounting; do you really have the height for OP engine over your legacy chassis?)

If you do the verisimilitude correctly this could be a fun article for MR, or perhaps a 'what-if' for the Classic Trains people...

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Posted by NWP SWP on Sunday, December 24, 2017 12:55 AM

Now here's another choice for the body, do I make the body extend to the ends of the locomotive like a Milwaukee Road boxcab? Or do I give it a little porch like an NYC R motor? Or a big porch like a P motor? Decisions, decisions, decisions...

One answer is build it with the big porch out front but the back extends to the end of the locomotive and build another either A unit identical the the first or build a B unit that has no porches and the body stretches the length of the unit... farther down the road build either two Bs or an A and B to make an A-B-B-A set! Mischief

Steve

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Posted by NWP SWP on Saturday, December 23, 2017 1:07 PM

Yes there will be that many powered axles... I'm going to get two Trainmasters and cut off the hood and cab, put the two motors inside each and put two B trucks on each motor and the two middle B trucks will be attached together to make a D truck... then the boxcab body goes on top of that...

Steve

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Posted by Bayfield Transfer Railway on Saturday, December 23, 2017 12:56 PM

Is it REALLY going to be B-D-B + B-D-B, or will it be 2-D-2 + 2-D-2, or 2-D-B + B-D-2, or some other possibility?

16 powered axles seems pretty ambitious.

 

Disclaimer:  This post may contain humor, sarcasm, and/or flatulence.

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Posted by NWP SWP on Saturday, December 23, 2017 12:29 PM

Well I was racking my brain trying to figure out how to make the cab, then it hit me, I could cut some roof off an Alco PA and make that the front of the cab! Ed that sounds like an interesting kitbash project...

Steve

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Posted by 7j43k on Saturday, December 23, 2017 9:38 AM

The Milwaukee Bipolars lasted until about 1962.  And were then scrapped.

I wonder what would have happened if someone had bought one at scrap prices and decided to dieselize it.  Not as a road engine, but as a heavy switcher--maybe a transfer engine or a hump loco.

I see by a drawing that there were single axle lead trucks.  Not necessary on a switcher.  So then the arrangement would be B-D-D-B.  Hmmmmm.....

 

If I needed another project (and I DO, you know), this one would be a fun free-lance.

 

One thing:  I'd try very hard to make the body NOT look like I had bought an off-the-shelf shell and fiddled with it.  I would want it to look "homemade" (which it would have been).  There'd be a lot more scratchbuilding than kitbashing.

 

Ed

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Posted by tstage on Saturday, December 23, 2017 7:29 AM

Have you done ANY kitbashing projects before - i.e. small or large?  Or, will this be your first attempt at it?

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Posted by NWP SWP on Saturday, December 23, 2017 1:29 AM

The Japanese locomotive is a close match... But the price tag isn't...

Here's a New Haven that looks close too...

How hard would it be to bash the front end from styrene? I have two options first is have an almost exact replica of the NYC P-3 cab, second is a cab similar to the New Haven but without the little "brim"...

Steve

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