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This idea pops up in the H.O. Forums and Boards now and then, but has anyone out there tried it in 1/32 scale ? I could see how the design can limit the clearence of some bodies and It also means having no brakes, but there must be a few builders who can explian its merits ?

Chet
 

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Brian Ferguson
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I can't comment on direct-drive in 1/32, though I suspect it would be less than effective on the larger cars.

Direct-drive obviously lacks gear-generated torque, so acceleration is much lower. Braking is also much weaker. Top speed, however, can be much higher. DD cars must be light (and therefore not stuck down with magnets either) to avoid overheating the motor. DD cars, in HO, are in their element on fast tracks, racing against non-mag cars.

Ed Bianchi and Gerry Cullan are two HO "experimenters" who have been playing with DD for some time. Ed, under his "HO RacePro" business name, has sold many of his DD cars, called "Rattlers" over the last few years. He also manufacturers the "Slide-Guide", an HO version of a guide flag which allows most newer HO cars to run on 1/32 plastic track or routed track. In exchange for hosting his info on my web site, he supplied me with several Rattlers as they evolved, including one that was specially built for me, along with some parts. After receiving the first one, I built my routed modular track, just to have something to run them on!

They require a different style of driving but they can be extremely fast. The trick is to maintain momentum by being very smooth. The Rattler corners quite well, so if you can exit the turns well, you will be going fast enough that the lack of torque won't be a problem and the car will rocket down straights. Of course, the brakes are next to non-existent, so you must brake earlier, but the car enters turns very well, at higher speeds than you think possible - if you get it just right. I have several standard HO cars modified with the addition of Slide Guides and they can't get within 1/2 second of a Rattler on my 48 foot track. (I don't have the times at hand, but I believe the Rattler's best is 5.7 seconds and a tuned-for-wood Super G Plus has yet to do better than 6.2).

The Rattler gets its name from a floating brass "rattle" plate that sits atop the main chassis pan. The faint sound of the rattle plate is indeed the only audible sound that the car makes. On a routed track, the car is so eerily quiet that it can be tough to drive because you just don't hear much of anything!

Dennis, those pics are lifted from the new HO RacePro web site that I did for Ed. Lots more info and pics, including his latest experiment, are at:

HO RacePro

Tropi... yes, the same Fergy... small world, isn't it?
 

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Al Schwartz
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I built a direct drive 1/32 Mercedes W 196 streamliner for the first Marconi Proxy race using a double ended N-gauge motor. You can find a picture of it at:

http://electricdreams.freeservers.com/photo.html

It was fast and very smooth but, as noted above- not much in the brakes department. As the caption says, it needed the silicone tires which aarrived late. I have not gone back to the experiment to see if it could be improved - partly because those little replcement motors are expensive ( about $25 as i recall)

EM
 

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Al Schwartz
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The motor came from "Proto Power West:

http://www.ppw-aline.com/re-power.htm

I don't recall which one I chose but the dimensions are all on the web site. As I recall, these motors have 2.0 mm shafts so they must be sleeved to fit the typical 3/32 axle hole. I believe that the same site lists sleeves (at an outrageous price) that will take the shft to 3/32.

The finish on the model is burnished Testor's metallizer. It looks better in the picture than it does in the flesh! (Without clear coating, this is a very fragile finish but clear coating degrades the metallic appearance.

EM
 

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All these names from a few years ago falling into place now!
Allan Schwartz!
On my other PC, if I can ever get it going again, I have notes on the exact motor you used! Not cheap, for sure you are right there.
 

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Russell Sheldon
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I seem to recall that AJ's / Twinn-K produced a cylindrical rubber "pinion" that replaced the conventional pinion and enabled a friction direct drive by way of the "pinion" driving the rear wheel (obviously in a sidewinder set-up).

There have also been gearless belt-drive cars, probably the best known being the Parma "Whisperjet" and the DRS 1/24th drag motorcycle the most radical.

Fergy, do you have any pictures of the "Mico-Cuc", please? I've seen reference to it and would love to see what it looks like.

Kind regards,

Russell
 

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Hmm, EM, Allan, Mr Niceguy, whatever. Thanks again! A fascinating site, and I'm very tempted with those little cans. Anything different, anything new....
And thirty dollars is only about fifteen quid to us affluent Brits these days.
 

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Russell Sheldon
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Thinking about it, direct drive may be the way to go for rail-racing -- no pesky gear to get in the way of the danged "raised slot"...


Might consider using one of these....



13,000 RPM 5-pole Pittman DC-84, with 3/32" armature shaft that the wheels can be attached to.

Kind regards

Russell
 
G

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Russell,
Great idea.

Now rail racing is all about being smooth and keeping the car speed fairly constant as rail cars work best this way.

I think this could be why some slot racers find it hard to adapt to rail racing.

I would be very interested to see a rail car built with that motor.

Best wishes,

Jeff.
 

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Al Schwartz
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QUOTE I would be very interested to see a rail car built with that motor.

Not in 1/32 with that motor unless it is a model of large load earth moving machinery!

Now, I do have a swiss-made Maxxon motor that I acquired some years ago - double ended with 3mm shafts - may need to give that a try in 1/24 to run at Las Vegas on the King.

Acceleration is mostly a matter of choosing the motor parameters - there are plenty of "real life" applications fo direct drive motors in high torque starting applications, viz. small compressors and large electric locomotives which have been made with the armature wound on the axles.

Brakes could be the bigger issue. I have doodled a mechanical brake held in the "off" position by power applied to the car (problem at low power levels but the priciple is the same as air brakes) or a bit of circuitry, analogous to the continuos lighting systems, to store a it of energy on board and then apply it, in reverse, when the applied power drops to zero.

So many projects....so little time....

EM
 

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Brian Ferguson
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QUOTE Fergy, do you have any pictures of the "Mico-Cuc", please?

Russell, I sure do! Just takes me awhile to find stuff...
Organization? Me?


Here's a couple of pics of Gerry Cullan's prototype Micro-Cuc. Gerry went on to sell something like 250+ of the final hand-built chassis. If anyone has ever tried scratchbuilding an HO chassis, you'll have some appreciation for the magnitude of that task!




The Micro-Cuc center chassis is soldered to a brass angle, which is soldered to the motor can. Hinged side chassis members carry the front axle and body.



Obviously, the design was inspired by the famous Cox "La Cucaracha" from the 1960's.
 

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By-the-by, and since the man who knows is around, was the Iso-Fulcrum chassis a Cox innovation, or was it their adaptation of a current design? Who did come up with the idea? It was radical at the time, and I still love it.
 

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Graham Windle
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Fergy/EM I built a d/d ho slider last year when I saw the micro cuc I have also tried it in 32nd about 10 yrs ago .I found them to be very poor in performance,I may just have to give it another go though using neo mags in the motor this would counter the poor brake and aceleration .But the biggest problem I forsee using this idea in competition is that in a heavy impact there is a chance of bending the motor shaft .In a normal set up bending an axle is easily repairable not so with d/d.
 

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Brian Ferguson
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Grah, I agree that it probably won't work well in 1/32. The track would have to be super fast and the motor super torquey (as you said). I hadn't considered the "bent axle" problem because it doesn't happen in HO - the mass of the car is quite small.

I found DD impressive in the smaller scale, but I was running on routed tracks that were faster than normal HO layouts. Without magnet traction the inline cars were poor at putting down the power and the DD car was just sooooo smoooooth.


Howmet, I believe that "iso" chassis had been done first in the scratchbuilt arena and that Cox, shortly thereafter, built their production version. Perhaps Russell or PdL could confirm the actual origin.
 

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Graham Windle
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Howmet if were talking s can size to get it between the wheels then I would say add as many extra armature plates as you can (probably about 5) and wind with say 170 turns of 38 swg 1 degree advance just to ensure the motor runs fastest in one direction and fit a set of neo mags .the whole set up would probably only turn at about 15000rpm but have masses of torque ,a hardened shaft will no doubt help.I can see Ill have to do it and see.
 
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