Just one example.

Way back in the dark ages/1960. I had a friend who took an Athearn GP7/9 and all he did was put multiple bands on each axle/as many as would fit. And added a ton of weight to make that loco "heavy". That loco could pull so many cars we gave up trying to find the maximum number. Over 100 for sure. As for your video, that was the major problem with those locos. They ran 400 mph. IMHO that video was way too fast of running. A train that long might never go that fast. ? I am not an expert. I just don't like MR trains running like jack rabbits. We can not duplicate the prototype that exact. There aren't many MR that have 1/87th of 400 miles of mainline. We did find with that particular loco that it didn't like low speeds. So it could never be used as a yard bird/switch engine. But as mentioned, on the main with a long train, looked fantastic.

the high speed

could possibly be reduced by adding some kind of jackshaft arrangement?  Athearn came out with their sweet gear drive soon after these so never any incentive to try and make the rubber band drive use-able ....DaveB

If you replaced the motor

If you replaced the motor with a modern 5 pole, you could probably get better speed out of them. Personally though, I'd just look at using NWSL stanton drives.

Jack Rabbit Starts & Speeds

Of course something would have to be done to fix these bad habits. My initial thoughts are with more modern and big variety of motors,...plus dcc control this could be solved.

I think I ran across a video where someone had modified their old small switcher (like a docksider) to run with a rubber band drive train,..but I can't recall where?

The simplicity is the problem

The simplicity of the rubber band drive is the problem - not enough reduction, rubber band creeps one way or the other on the shaft, etc.  Rubber band drives are cheap.  If you want good, I think you’re almost certainly better off looking into chain or toothed belt drives to secondary reduction in the truck like some O scale mechanisms, or just a good quality all gear drive.

The simplicity is one of the

The simplicity is one of the attractive features,  and the cheapness makes experiments attractive.

What if I were to utilize gearhead motors to get the gear reduction? ......they are pretty inexpensive HERE

And since they are not double shaft ended, maybe put one at either end on each individual truck of that 'pusher car',....something akin to this but no gears on the wheels,...rubber bad drive.

Rubber band drives

Does this website help?

Or this suggestion for axle hung motors?

Best wishes 

Eric 

Thanks Eric

That belt site is most interesting, ....and likely most applicable.

Have a look at this clean

Have a look at this clean installation,   https://modelrailroadforums.com/forum/index.php?threads/rubber-band-drives.34051/#post-515701

Just a quick guess but I think the gearing likely represents a reduction of 10 to 1. Then the rubber band reduction of another 10 to 1. So the 8000rpm motor goes to 800, then goes to 80 for the wheels??

The Kingstone photo

The Kingstone photo is interesting. The two diameters shown do not seem correct. The 0.5" diameter pulley seems much bigger than the 0.3" diameter pulley.

It's also interesting that the motor is a reduction drive but the pulley and rubber band system gears it back up again.

@ Jeff

The reason for that was that the gear reduction drive was to slow by the time it got through the worm gears. That motor at 12 volts would reduce the speed through the gearbox of the shaft to 10 rpm. I reduced the gear ratio by modifying the gear box by taking out a reduction section for a faster output speed. It was still not enough for the top speed of the engine. Somewhere on my computers I have a video of this mechanism running. If I ever find it, I'll post the video. By the way a lathe will be needed to do all that modification. Sometimes a mill also helps.

Bernd

Belt Drive Video's

Here' the one Brian showed on the F unit I built. It's got a belt drive going through an eddy current clutch.

These are HOn30 boxcab drives I built using "N" scale DD-40 trucks. They are called the twins.

This one is a modified truck from an MDC Shay. I narrowed it to TT scale and added the belt drive.

This was the first test of one Brian posted on this thread. Notice how slow it is at 12 volts going from right to left. That was the reason to switch the pulley's around for a faster chassis. The second video is with the one shown in Brians post. I was testing how many cars a belt drive would pull before slipping.

This is the faster version, with the .5" pully driving the .3" pulley. The second run is at 12 volts.

These are all my belt drive experiments. Would I use them for larger engines? No. they do slip, they due stretch and they due take a set if they are in one position for a long period of time. The belts I use are .09" square belts designed to run in a V groove pulley. The only source I have been able to find is Nigel Lawton in England. Hollywood Foundry also used these belts in his drives, but he is no longer in business. I was able to do these projects having a lathe and mill. Without these I don't think it would have been possible to make the pulleys, make any of the modifications and any of the brass parts of the chassis or engines.

Bernd

@ Bernd

Thanks for all those videos. I'm going to have to watch them a few times each. Nice to see that someone has taken such an interest in alternative drives.
 

So you do not quite agree with Nigel about the durability of the belts/bands that he uses?

Did you find the use of the 'enlarged diameter axles' , as used on a number of those early rubber band drives, objectionable? I don't see any of your experiments utilizing such an arrangement?

Belt durability

I found Nigel's website quite a number of years ago and ordered just his belts, I'll call them belts because of the material being used. They are not meant to be stretched like rubber bands. I did one experiment and then set it aside for over a year. When I came across that project, I tried to run it. I had noticed that the belt had taken a set to the curvature of the pulleys and had also stretched a bit. I didn't exactly go by the chart he shows on his site for how long you can stretch the belts. I may have stretched it a bit too far. I would use the belts for smaller engines that may only pull a couple of cars, such as in switching moves.

I'm going to be honest here and tell you I really don't care for the direct drive rubber bands on the Atheran engines. They are way too fast and don't have a nice slow speed. I would rather use a belt drive to step down the speed of the motor before applying the RPM to the worm gear, such as on the Tyco CR-4 loco. 

I believe belt rives can be used but not for a direct rive from the motor to the wheels. Belt should be made from neoprene like Nigel's belts are. Having only him as a source is problematic in future use if he no longer sells the belts. As I said before, I have not been able to find another source of these belts. I'm sure Nigel won't let that out of where he gets the belts from.

If you go and read the write ups on the CLAG (Central London Area Group)  http://www.clag.org.uk/ Click on the picture with the CBS Gallery words. It will give you an idea of what I think model locomotives should have to track properly and keep all wheels in contact with the track. I think this is more important than adding a booster drive in the tender. Just my opinion. Also look at their "Deflection of Beams" article. Interesting information. I think that's why they call themselves Model Engineers and not model railroaders. 

Bernd

Axle RPM's

What sort of RPM's are required of an axle with 36" scale wheels to reach scale speeds of 10mph to 60mph?

Lazy in my old age....is this correct for our scale models?

36" x 3.1416 = 113.09"/12" = 9.42'

60MPH = 1 Mile per minute, or 5280' min / 9.42 =                         560.5 RPM at 60 MPH
10 MPH = 5280 x 10 = 52800'/hr or 880'/min.  880' /9.42' =            93.4 RPM at 10 MPH

My earlier comment.

Back a ways, I mentioned an early day experiment. He used multiple rubber bands on each axle. 2 reasons. 1 to reduce the effect of stretching. 2 to allow for breakage. One rubber band could break after a bit. Using multiple bands helped that somewhat. Not a cure, but just a help. So with 'neoprene', it appears that there's no room for more than one belt. So the bottom line to me is "what do you do about the stretching"? Put another way. Wouldn't any belt, whether plastic, rubber, or neoprene, always have some stretch? Is there any other material that won't stretch?

is this for real?

So Brian, is all this thread and the other one just talk, or are you actually planning on doing some modelling at the end of the discussion? Or are you planning on trying to schnorr someone else to do the work for you? 

I am collecting information

@EW

I am collecting information on past experiments etc. I am real interested in doing some experiments on some ideas, but not those so involved as to require machining tools,..(that I don't have). I hope to dig up some 'lost experiments' that may not have seen of daylight.

I don't have time to do those experiments right now as I want to continue on the building of my layout. Some of those chores can be a bit boring, so brain storming this rubber band drive subject can be fun.

I'm still not convinced that the simple forms put on some of the early models are totally obsolete, particularly with modern day tech and materials.

Per the other thread on a diesel pusher/helper I am definitely going forward with that idea. I have a couple of those aux water tenders, and I am buying a few more of those Atlas engines when I can find them at a good price.