Electric drive motor specs

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Glenn Brooks
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Re: Electric drive motor specs

Post by Glenn Brooks »

Mike, that’s an interesting loco. Was it built by Sandley? Any background on the park you mentioned? I don’t recall hearing about that previously...

Looked at a couple of electric vehicle sites last night. Apparently several manufactures make or sell electric motors in the 7-11” diameter range for EV conversion. Again, the battery pack is the big limiting factor. Also their on line calculators use different functions and terminology for calculating power needs. I don’t have gearing and speed info for 6 speed transmissions, for example. And don’t need to go 60 MPH. Well, that would be cool, but not likely to achieve...

Also, the MC and boat EV hobbyists sometime use forklift motors and batteries. So plan on looking into that aspect.

Anyway, next up, pull the trucks from under the goat and see how much room I have to play with in the frame. And start scrounging for a source of golf cart or forklift batteries.

Glenn
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Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

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Pontiacguy1
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Re: Electric drive motor specs

Post by Pontiacguy1 »

I still say that this is a worthwhile restoration/upgrade, but with reasonable expectations for its performance. This locomotive, weighing in at around 1000 lbs, or even just a bit more, could make a very good locomotive for track maintenance and general work, shunting, and occasional light passenger hauling. It would be a lot more convenient to take this thing out for a spin to check your track, or haul one ballast car, take supplies to a trouble spot, etc... than it would to have to start up and get out your larger, heavier locomotives, especially if they are steam.

In my earlier post I mentioned a 60's VW beetle not being able to pull a 30 foot camper trailer. That doesn't mean that the VW is terrible and can't be used effectively, it just means that it's inadequate for certain jobs. It might be ideal for other, smaller jobs. My point is: Don't give up on this. I think you could have something really neat and useful, it just isn't going to be able to pull that huge train you were thinking about.

And that's another question: What does a 15" gauge empty freight car actually weigh?? Let's say a 15" gauge gondola. Would that be around 800 lbs?? maybe 1000 lbs? 1200 lbs?? I can pretty well guesstimate what a 1/8th scale freight car will weigh, but not too much experience with the larger stuff.
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Erskine Tramway
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Re: Electric drive motor specs

Post by Erskine Tramway »

Glenn Brooks wrote: Sun Oct 11, 2020 11:49 am Mike, that’s an interesting loco. Was it built by Sandley? Any background on the park you mentioned? I don’t recall hearing about that previously...

Glenn
The railroad was called the 'Quinsippi Central'. It was located on the abandoned CB&Q RR grade on Quinsippi Island off Quincy, Ill. In 1965, Elliott Donnelley bought our 'second' locomotive, Atlantic #127 and our old, eight passenger, coaches to donate to the Park district. We delivered the 'diesel' in Nov, 1970. Eventually, the railroad failed, and the equipment lay dormant for many years. I suspect that, mostly, the Park District got tired of taking care of it. Now, the coaches, much the worse for wear, have been returned to The Dells, and been rebuilt. The 'Masonite' roofs didn't survive very well. A fellow in Texas owns the two locos.
48618_16.jpg
Here's my folio of the diesel. It's a scan of an original 'Diazo' print, that is pretty faded...and it won't all fit on my scanner. The original loco was built before I started at Sandley's in 1962. For years, it was stored in the shed down at 'The Camp'. As built, it was a giant 'Hi-F' drive. It had a 'lineshaft' just below the roof, driven by multiple belts from the automatic transmission, which, in turn, drove the axles by multiple belts. It was really fast, but not very powerful, kind of like the HO Scale Athern 'Hustler' :shock: That's why the drive was changed for Quincy.
QC 940 folio mail.jpg
The loco is 36" wide, and 5'-4" over the top of the stack, 4'-9-1/2" over the body.

Mike
Former Locomotive Engineer and Designer, Sandley Light Railway Equipment Works, Inc. and Riverside & Great Northern Railway 1962-77
BN RR Locomotive Engineer 1977-2014, Retired
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Erskine Tramway
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Re: Electric drive motor specs

Post by Erskine Tramway »

Pontiacguy1 wrote: Mon Oct 12, 2020 8:54 am
And that's another question: What does a 15" gauge empty freight car actually weigh?? Let's say a 15" gauge gondola. Would that be around 800 lbs?? maybe 1000 lbs? 1200 lbs?? I can pretty well guesstimate what a 1/8th scale freight car will weigh, but not too much experience with the larger stuff.
We always figured that our 20-foot long, twelve-passenger, steel framed, clerestory roofed, coaches on the R&GN Ry. weighed a ton, and a carload of 'average' passengers another ton. A gondola would be shorter, and not having a, comparatively heavy, roof, would probably go around a half-ton, depending on how it was built.

Mike
Former Locomotive Engineer and Designer, Sandley Light Railway Equipment Works, Inc. and Riverside & Great Northern Railway 1962-77
BN RR Locomotive Engineer 1977-2014, Retired
Glenn Brooks
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Re: Electric drive motor specs

Post by Glenn Brooks »

I was wondering the same thing, and worked up some figures about car weights just yesterday. For my 10’flat car, (12” ga), with 3x1 rectangular steel tubing, I came up with a total weight of around 500-600# for the chassis and trucks. Add 8 passengers @ 200# each = 1600#, or 2,200 # gross weight. 3” channel iron weighs about the same as 1x3 tubing...

Building a larger 12’ or 14’ passenger coach and adding sides and roof, bare bones, could easily reach 1,000# chassis weight, and as Mike related, 2000# for a 20’ coach.

Also, larger scale coaches probably would need 4” channel or 1x4” tubing for the frame, so weight per foot of material goes up, with the larger size cars.

Interesting to think about aluminium frame construction. Which I‘ve never done. The weight would go way down.

Glenn
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Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

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Pontiacguy1
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Re: Electric drive motor specs

Post by Pontiacguy1 »

Guess I was thinking about your locomotive being able to pull 2 or 3 loaded gondola cars. maybe 4 to 6 people each. That or maybe a couple of ballast cars, or a flat or two with supplies on it. Somewhere around 3000 to 4000 pounds trailing weight. That's what I was thinking about, not a 20' long car with a roof that can haul 12 passengers. Maybe could haul one carload like that.
Glenn Brooks
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Re: Electric drive motor specs

Post by Glenn Brooks »

Pontiaguy,

Your right I think, for this center cab. We haven’t pulled the trigger on a 15” ga live steam club yet, but it’s feasible to do so in what amounts to a commercial environment, so I keep drifting off into fantasy land estimating what it would take to convert to 15” Ga and maximize this little goat to work in that environment.

For this little center cab, your call on a max of 2 or 3 riding cars, with 3 -4 seats each is spot on, a much more realistic design. That would be a (corrected weights) 4,000 - 6,000 max weight consist - much more realistic, and potentially doable with readily available motors, depending on tractive effort.

Also I would certainly be happy with less for my Backyard pike. Also, it would be cool to run tandem locos or build a Powered B unit, hooked up to one controller. That would add some interesting additional capacity. Lots of options, just like the big boys...hahaha put a small motor on every axle on each car! Man that would be a puller - up 5% grades maybe, just like the commuter rail going in down the street.

BTW, I found a whole bunch of electric motor sizes for go karts and e-motorcycles up to 2000 watts capacity in the $100-$200 price range, available on line. Also apparently some 7” and 9” series wound forklift motors. These seem to be really robust motors, cheap via surplus. So researching and trying to learn more about that possibility, as well.

Glenn
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Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

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Steggy
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Re: Electric drive motor specs

Post by Steggy »

Glenn Brooks wrote: Mon Oct 12, 2020 12:39 pmInteresting to think about aluminium frame construction. Which I‘ve never done. The weight would go way down.
Actually, you might be disappointed at the weight savings, not to mention complications related to fabrication.

For loading purposes, a railroad car may be treated as a simple beam supported at two points (the trucks). In calculating how much loading a simple beam can support without permanent deformation, a key number is Young's modulus, which in a simple beam may be thought of as a ratio between applied strain (e.g., bearing the supported load) and bending due to plastic deformation of the material from which the beam is made. The higher the Young's modulus the more resistant to deformation the material becomes and therefore the the beam will have greater resistance to bending under load.

Steel is typically specified as have a Young's modulus of 29,000 Kpsi to 30,000 Kpsi—it varies somewhat with alloys; 29,000 Kpsi is applicable to mild steel. Aluminum's modulus is typically around 10,400 Kpsi, depending on the alloy (the quoted number is for 6061). Without going into all the engineering specifics, in order for an aluminum beam to exhibit resistance to deformation at the same level as a steel beam, and assuming the same load applied in the same fashion in both cases, the aluminum beam will have to be such that it appears to be nearly three times as massive as its steel counterpart. The tricky part is Young's modulus predicts the ratio of strain to deformation, but the actual conditions are complicated by the beam's cross-sectional shape, the manner of support and the degree of focus of the load.

Then there is the matter of fabrication. Unlike steel, aluminum can be unpredictable when it comes to welding. Variables present during the welding process can result in a weld with substantially different metallurgy than the base metals. Most hobbyists lack the resources and skills required to control the process to the degree required to produce consistently sound aluminum welds with predictable properties. For this reason and others, aluminum fabrication will be more reliable with riveted or bolted joints. It goes without saying that neither method is nearly as convenient or time-efficient as welding.

Cutting to the chase, I don't believe you will achieve much weight-savings using aluminum, due to the need for substantially greater mass in the car's frame to resist the bending loads. Furthermore, steel's resistance to fatigue is substantially greater than a same-sized mass of aluminum. Railroad carbodies are subjected to dynamic twisting moments, as well as static bending ones, twisting being where the fatigue issues arise. Lacking sufficient fatigue resistance, cracking and outright fracture may arise relatively early in the car's life. Combine that with material cost and difficulty of fabrication and I think you'll appreciate why most railroad cars are fabricated from steel.
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Erskine Tramway
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Re: Electric drive motor specs

Post by Erskine Tramway »

Glenn Brooks wrote: Mon Oct 12, 2020 12:39 pm
Also, larger scale coaches probably would need 4” channel or 1x4” tubing for the frame, so weight per foot of material goes up, with the larger size cars.

Glenn
Hi Glenn...

Our coach frames were made of 2"x2" 'T' iron, with truss rods. The two center members went all the way out under the platforms, and the outer ones were the length of the body. It was a welded assembly, with two bolster plates, angles on top at each end to 'define' the body length, and two angles below to support the truss rods.
117308503_1532446626959767_3816697484064509183_n.jpg
Here's a picture of a gondola that the Preservation Society built, but I know nothing about it, except it looks to be about twelve-feet long, as best I can scale it from the photo.
59639397_2232072990219912_5313258098616434688_n (2).jpg
Mike
Former Locomotive Engineer and Designer, Sandley Light Railway Equipment Works, Inc. and Riverside & Great Northern Railway 1962-77
BN RR Locomotive Engineer 1977-2014, Retired
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Re: Electric drive motor specs

Post by Steggy »

Erskine Tramway wrote: Tue Oct 13, 2020 9:29 amOur coach frames were made of 2"x2" 'T' iron, with truss rods.
Rectangular steel tubing can work well as a center sill, and for any given weight of material, will be two to three times more resistant to bending than T-iron. Also, a tubing structure will be stiffer in torsion and will make it easier to attach things to the framework.

The control car for my F7 has a frame whose center sill was made from 11ga × 2 × 4 rectangular tubing (4.58 lb/foot) in the middle and 11ga × 2 square tubing (2.94 lb/foot) at the ends. 14ga tubing (3.27 lb/foot and 2.14 lb/foot, respectively) would have been more than adequate, but I had lots of 11ga stuff laying around from other projects. Also, I wanted a fairly heavy car to improve ride quality and reduce the likelihood of a derailment when running over debris laying on the rails.

Control Car Frame, Plan & Left Side Elevation
Control Car Frame, Plan & Left Side Elevation

The 60" dimension at the very bottom of the drawing is the center-to-center span between truck kingpins.

According to my calculations, a static load of two people weighing 200 pounds each, plus the carbody's weight of 180 pounds, would produce about 0.001" deflection in the center sill. Testing with a load of sandbags substituting for riders couldn't confirm that number because none of my measuring tools could detect any deflection.

For something like the ride-in coach illustrated above, a rectangular tubing center sill and a ribbed carbody structure would produce a high degree of strength with reasonable weight, and would have some "crashworthiness" should a derailment cause the car to go on its side. Since the coach has straight sides, ribbing could be done with lightweight channels or thin-wall, structural grade rectangular tubing, the latter which I used to build the "skeleton" for my F7's carbody.
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Re: Electric drive motor specs

Post by Erskine Tramway »

BDD...
That's fine. Our coaches were all wood above the frame, except for the glass in the end 'doors' and the sheet tin used in the sides of the roof. I had a few derailment's at speed, but it never laid one over. I also looked back one day and saw a couple college age kids standing up in the doorways and leaning out. They didn't succeed in tipping the car over either...though had they, they'd have been on the bottom of the pile.

Steel cars are noisy inside.

Mike
Former Locomotive Engineer and Designer, Sandley Light Railway Equipment Works, Inc. and Riverside & Great Northern Railway 1962-77
BN RR Locomotive Engineer 1977-2014, Retired
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Re: Electric drive motor specs

Post by Steggy »

Erskine Tramway wrote: Tue Oct 13, 2020 11:48 pmSteel cars are noisy inside.
Just like a real railroad car. :D
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