Hi guys,

I know I will probably need to take pictures of this thing, but bascially, I have a brass New York Central T3 Electric, produced by Alco models, that has a Spring-Belt drive.

Essentially, the electric has a wheel arrangement of B-B+B-B. The two center trucks are powered, and the outer ones are dummies (all were powered on the prototype).

Located in the boxcab is a motor with a pair of pulleys on each end. These pulleys are grooved and have a pair of spring belts (for a total of 4, 2 in each truck) that travel down through the frame into the truck and connect to another pulley, which drives the worm gears and wheels.

The problem is that the spring belts seem to be catching on something, and so the pulley slips underneath the springs on the motor end. This drive is so weak that the model can barely propel itself on one truck (and I'm starting to doubt it can move very far even if both trucks got rolling).

The prototype was able to haul some fairly long trains (such as the 20th Century Limited) into Grand Central Terminal, so I wanted to try and at least get close to a respectable passenger consist.

Is it possible to modify or upgrade the spring drives, or will I need to do something more dramatic?


Ken Lawerence, who appeared in RMC a couple times, rebuilt this make and type of locomotive with a pair of Bull-Ant powered trucks, but these are $93 a piece, and they are shipped from Australia! It would be very expensive to do this (almost as much as the model!), and it would require some surgery.

Here is Ken's Westchester & Northern. It used to have Catenary on it and New Haven style electrics, but it looks like he converted to third rail!

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Here are a pair of photos on the the Hollywood Foundary site of the conversion. I'd need to cut a pretty big hole in the floor, and then I'd need to solder in the bolsters. Supposedly there was an RMC article with more details, but I can't find it. I'm POSITIVE I saw it online once, but I cannot find it there either.

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I think the problem you've got is that 1970s brass diesel and electric locos hardly run at all. The belt drive is one problem, that I hadn't thought much about. The belt drives were common on Suydam interurbans, which I guess was less of a problem, since they pretty much only had to move themselves. I don't know what the wheel diameter or wheelbase is on the T motor -- the issue would be to find a matching plastic diesel truck that might somehow be used to replace the brass version, with extensive reworking of the drive train on top of that. Regearing isn't an option if you still have the belt drive. That means the radical solution of the bull ant drive. But consider this: say you spend $200+ to get a workable loco by adding the bull ants. What would be the current price of a new T motor from Overland, assuming anything like that ever comes in again? Or what would be the price of a more recent Overland?

You may wish to check out NWSL's Stanton Drive (You'll need to scroll down 5 or 6 pages). Supposedly it can be fitted with different size wheels, and may be convertible to using your existing drivers. This won't likely save anything cost-wise over the Bull Ant drives, but you may be able to power all four driver sets. With the space in the body shell no longer needed for the motor, you could probably pack enough lead in there to pull a fully-modelled Century. If you need more info, contact Dave: he may be able to offer other alternatives, too.

Wayne

jwb Wrote:. I don't know what the wheel diameter or wheelbase is on the T motor

Unfortunately, I don't have the scale plans for this locomotive. However, here are the dimensions as measured with a scale ruler-

Wheel Diameter- 36"

"outer" truck wheel base- 6' 9"

"Inner" (drive) truck wheel base- 5' 6"

jwb Wrote:-- the issue would be to find a matching plastic diesel truck that might somehow be used to replace the brass version, with extensive reworking of the drive train on top of that. Regearing isn't an option if you still have the belt drive. That means the radical solution of the bull ant drive. But consider this: say you spend $200+ to get a workable loco by adding the bull ants. What would be the current price of a new T motor from Overland, assuming anything like that ever comes in again? Or what would be the price of a more recent Overland?

I don't think there is a diesel truck out there compatible with this engine. Even if there was, it would be almost as much of a nightmare to intall as the Bull Ant method.

I can see your point though. I didn't spend anywhere near the full price of this locomotive, but i could certainly get most of the cost of a nicer model by selling this one and throwing the money I would have spent on bull ants into the mix. Still, I think the "next level" of New York Central electrics tends to go for WAY over my budget for one locomotive. This T3 was a target of opportunity.

doctorwayne Wrote:You may wish to check out NWSL's Stanton Drive (You'll need to scroll down 5 or 6 pages). Supposedly it can be fitted with different size wheels, and may be convertible to using your existing drivers. This won't likely save anything cost-wise over the Bull Ant drives, but you may be able to power all four driver sets. With the space in the body shell no longer needed for the motor, you could probably pack enough lead in there to pull a fully-modelled Century. If you need more info, contact Dave: he may be able to offer other alternatives, too.

Wayne

I've had some experience with the Stanton drives for my MU cars. I have on installed in my Silverliner III, and pending better alternatives, I'll probably order a few for my other MU cars. These drives are kinda slow for my taste, though my 33" wheeled Silverliner can hit its 75 MPH timetable allowable speed when run by itself, so it should be adequate.

That said, the main limitation here is the wheel base. The only convenient place to install the Stanton drives would be in the center truck locations (this area has both the vertical clearance and an area to use the Stanton drive's mounting lugs to install it). However, the smallest wheel base offers is 6' 6", and that is "as small as they can go with this design".

The outer trucks have a compatible wheel base, but now the problem would be mounting them, there is simply no good way to install them out there.


But.... What about a sprocket and chain?

I've seen sprockets and chains in larger engines, but it looks like micro mark sells some very small sprocket and chain pieces. I'd have to break down the model and measure it, but it looks like I may have a winner. The sprockets themselves are only a few bucks, and a 1' length of chain is $18.

Would their be any drawbacks to this design? I placed the model on some 18" curves, and the truck swivel was minimal, I imagine the chain could still function with this minor twisting.

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I would like to remember to my VGN class AE rebuilding project where I plan tu build to rubber ring drives.



The last idea is inserted into drawing - I replaced the single rubber rings by a double ring drive. And I'm sure that it should work!
Unfortunately my construction is yet a plan and so I can not show you practical results.

modelsof1900 Wrote:I would like to remember to my VGN class AE rebuilding project where I plan tu build to rubber ring drives.



The last idea is inserted into drawing - I replaced the single rubber rings by a double ring drive. And I'm sure that it should work!
Unfortunately my construction is yet a plan and so I can not show you practical results.

Several years ago Roco of Austria made a model of the Austrian crocodile Class 1189. They had rubber belts in their power train.
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=> load the pdf for the spare parts pictured list.
# 18 is the rubber belt. It is simply an industrial O-ring normally used for gasket purposes. When new, everything is o.k. The loco will run very smooth.
But beware when the o-ring is aging. At first a little portion of the plasticizer migrates out of the o-ring. The O-ring becomes a little bit more stiff, but still will do it's duty. You can see it when the amprerage of the loco rises above the normal level.
Things grew worse as times goes by.
Until the so much plasticizer has migrated out of the host plastics and will lead to the loss of flexibility, tensile strength, embrittlement, and at least cracking. Tensile strength, that is what the O-rings will abducted a little bit here in this case, can be lost as soon as 2 - 3 years after. It does'nt matter if you run your loco or not, it is a matter of aging. In gasket purposes the O-ring will last much longer time because it has only to bear static loads.
So be wise and choose a common dimension of this ISO3601 O-rings that will be available for replacement in the future too.

My 2 Cents

Lutz

Well guys, I think I found a chain and sprocket combination that would work. My question is, should I also play with the gearing? I don't think I have a lot of extra space in the trucks, but I do in the body of the Boxcab.

Currently, the ratio of the pulley system is 1:1, but would it be better to install a bigger sprocket? This might increase the speed a bit, but i'm not clear how fast this thing can actually run on as it is, since it can barely propel itself.

I figure if I'm going to modify this engine, I might as well do it right. these parts are MUCH cheaper than any other option and seem to require the least amount of work.

modelsof1900 Wrote:I would like to remember to my VGN class AE rebuilding project where I plan tu build to rubber ring drives.

The last idea is inserted into drawing - I replaced the single rubber rings by a double ring drive. And I'm sure that it should work!
Unfortunately my construction is yet a plan and so I can not show you practical results.

This is nearly identical to the drive in my T3, except its one motor with double shafts. I would question whether or not it would work, but we'll see.

I think the gearing is in the trucks, so I probably wouldn't fiddle with the ratio in the drive.

I've got a bunch of old Suydams and Walthers with the spring drive. Most haven't been run for years, so...

BR60103 Wrote:I think the gearing is in the trucks, so I probably wouldn't fiddle with the ratio in the drive.

I've got a bunch of old Suydams and Walthers with the spring drive. Most haven't been run for years, so...

I keep neglecting to take pictures, but the gears in the trucks consist entirely of the gear mounted on each axle, which mesh with a worm gear mounted on a shaft driven by a pulley and the spring belts from the motor.

Last night I coaxed the model into running briefly, and this time with all the spring belts turning and no slipping I could detect, but it ran fairly slow.

The plan now is to replace these pulleys and spring belts with some sprockets. Fortunately, the pulleys are attached to the shafts by a little screw, so they should slide off easily.

The tricky part will be unsoldering the trucks (which consists of two sheets of folded brass fabricated into a box), so that I can gain access to the truck pulleys. I will also have to carefully remove on of the worm gears, but I imagine I can press these on and off, and use flywheel cement to reattach them if necessary.

I believe these sprockets have a smaller opening than the diameter of the shafts, but I should be able to open them up a little if I am careful, and still keep them snug on the shafts. Again, the loctite I used to affix flywheels will probably work here.

I purchased 4 small 8 tooth sprockets and 2 slightly larger 10 tooth ones, as well as a foot of chain. Hopefully they will arrive soon. so far as I've measured, they should all be able to fit. In fact, the diameter of the small sprocket over the chain is only slightly wider than the current spring belt system, and there is still plenty of room, relatively speaking.

Green_Elite_Cab Wrote:I keep neglecting to take pictures.....

Yeah, a picture or two would help those of us not totally familiar with the set-up.

Green_Elite_Cab Wrote:.....I will also have to carefully remove one of the worm gears , but I imagine I can press these on and off.....

I assume that you're speaking of the worm, and not the axle gear. Why would you need to remove it from the shaft? If you can open the gearbox, you should be able to remove the worm and shaft, either by lifting it out or by turning it. Then all that's needed is to remove the pulley and replace it with the sprocket.

If you need to enlarge the hole in the sprocket, drill it out to a size slightly smaller than required, then finish with a properly-sized reamer. If space within the gearbox is insufficient to accommodate the thickess of the sprocket, it appears that you can removed a fair amount of material from the mounting boss. You may also gain some adjustment depending on which way the gear faces, as the mounting bosses are different thicknesses on each side of the sprocket.

Wayne

Green_Elite_Cab,

I'm very interested in your replacement solution! Please share your pictures and experiences with us because I know that my planned belt drives will not be the best solution, a simple one however not the best. Thank you very much!