Bi-Polar

[E7]

As best I recall, the Custom Brass Trucks articulated and the bodies just sat on top of them. Maroon could tell you better, as he has had one apart.

[R.K. Maroon]

Here is a photo showing the chassis of the Custom Brass Bi-Polar, as separated from the body:


https://www.dropbox.com/s/2a1j9tz4h64m320/Custom%20Brass%20Bi-Polar%20As-Delivered%20Paint%2011.JPG?dl=0

The truck assemblies pivot on the floor of the cab sections. The force of the lead section is transmitted through the middle body section, which just floats on pinned drawbars relative to the two cab sections:


https://www.dropbox.com/scl/fi/90hps0g64aabzud49af5u/Custom-Brass-Bi-Polar-As-Delivered-Paint-03.JPG?rlkey=pw6724x74l3w5oecbcr1gk1qg&dl=0

It looks like the middle section is sitting on the main truck assemblies, but it is not. I would imagine that it is in the prototype, as the middle section contains the steam generator and associated water tank.

Note, with everything pivoted the way that it is, that there are seven individual sections (three body sections and four truck assemblies). In a curve all seven are aligned at different angles. I can't think of any other locomotive that is built this way, but I would be curious to know if there is one.

Jim

And found another photo:


https://www.dropbox.com/scl/fi/i6c1yhuqejdrds01xrov8/NJCB-Bi-Polar-Unpainted-02.jpg?rlkey=ycg7xtb1rwxlx05k9j6kk114m&dl=0

[E7]

Thank You Jim! You're the Best!

Rich

[sleepmac]

That looks like quite a beast. What was the horsepower rating?

Dan Weinhold

[bob turner]

That mechanism is almost identical to the MTH version. The biggest single difference is that it is four axles driven instead of three - something I have enough MTH parts and gears to fix if I suddenly want to.

A secondary difference is the rigidity of the frame - MTH has a very solid, robust frame with apparently steel spur gears. I wouldn't let those brass gears run all day long on a display layout.

I promised photos about a week ago. Note that my tooling is in the photo - the aluminum tube has a slot for backing the frame while I press drivers off their axle, and over on the right is my mandrel. Note the finished frame, where some drivers are "faced," and others not. The machined drivers on the table are all faced. My drivers are all about 1/16" greater diameter than the originals - I will ask my brother about the cost to machine proper tires in steel. Not sure he still enjoys machining. I do, but not 24 times the same thing.

[bob turner]

So this evening, after a very good day inserting a spar in the biplane wing (not trivial) I pulled SW's Bipolar off the display shelf with the thought of discerning how the bodies articulate.

Aaside from the diaphragms and electrical connectors, it is easy - you just pull the center cab upward. Two spring-like stubs stick out of the floors of the frames, and when you apply upward force, tiny fingers move to the center of the stubs, and the cab releases.

I am missing only three pieces (not counting bells) to assemble a complete second Bipolar - the floor of the center cab and two pantographs. I can probably capture pantographs, but I shall make the floor out of aluminum plate.

[up148]

So this evening, after a very good day inserting a spar in the biplane wing (not trivial)

I hope this was a team effort. Rebuilding wings is not for the faint of heart. Did you use a jig or ??

[bob turner]

Nope. All by myself. I have replaced Cub spars (easy) but never an all-wood wing spar.

To get the old spar out, I had to saw all the pieces between ribs out, then press the remaining stubs out of the ribs, remove nails, and clean up old glue residue. The new spar was then slipped into/through the ribs. I am guessing I have 30 hours invested. A new wing is ten grand exchange; I have no idea what a good used wing is worth.

But having a wing ready to go means we probably will avoid future damage, at least to that wing.

The "jig" on a fabric wing is the trammeling process. You want each bay to be perfectly rectangular. The washout is done on assembly.

Have we lost the model train community here? I think the Bipolar is fascinating. I shall look up the horsepower this AM.

Speaking of horsepower, did I mention I have been flying a 450 Stearman? Goes straight up!

[E7]

Have we lost the model train community here?

Yes!

[De Bruin]

Nope. Don't want to jump ahead of Bob's research but ....according to Middleton's excellent book/survey on electrified railways of the western hemisphere, Bi-Polars (EP-2's) had a max hourly rating of 3480 hp, which implies a slightly lower continuous rating of around 3000hp.
In comparison the original GE twin 2-B+B box cabs (Pelicans) also had approximately the same rating per paired units, 3440 max hourly, 3000 hp continous.
The EP-3 Quill's from Westinghouse were more powerful than either with max hourly at 4200 hp, the post war GE "Little Joes" had a continous rating of 5500 hp(!) which implies a short term hp in around 6000 hp. Mind blowing.

[sleepmac]

First of all, De Bruin, thank you for the HP knowledge.

Bob, seems most topics veer off course sooner or later. I think it is 'conversation'.

Dan Weinhold

[E7]

First of all, De Bruin, thank you for the HP knowledge.

Bob, seems most topics veer off course sooner or later. I think it is 'conversation'.

Dan Weinhold

Too many Cub exhaust fumes!

[E7]

Just for laughs, BIG LIZ:

https://en.wikipedia.org/wiki/Pennsylva ... _class_FF1

[bob turner]

I kinda liked the FF2 - I saw them hauling freight on the main line as a high school student in Berwyn.

I am all in favor of thread drift - I was just lamenting no train stuff, after I admittedly veered off into my daytime avocation.

I have the aluminum floor/articulating plate almost done.

[E7]

We'll drift some train wise: Pete, any progress with the new locale for the Atlanta club?