104 replies to this topic

[Jaeger Team]

Here in Italy we were, and still are, very passionate about Cucaracha.

Starting from 2017, for the fiftieth anniversary, the "Cucaracha Day" takes place in Roncole Verdi, an important event now in its 7th edition which has just ended.

I was encouraged several times to participate by my friend Dario Gueci, so I decided to prepare a prototype Cucaracha for next year (the regulation provides two categories: one with more or less box models, in the other more significant elaborations are allowed).
 
I hope to be in good health for the eighth Cuca Day and above all to finish the model in time because over the years I have become lazy and slow like a sloth.

Let's start!
 

[don.siegel]

Looks like a good start! 

 

I'm very tempted to try the Cuc Day as well, but it's right in the middle of several other events, so not very good timing. 

 

It's also too bad that the sponge tires are allowed here, instead of urethanes for the ECA Roncole Verdi event; just makes it more complicated sourcing and preparing two different types of tires. 

 

We all get lazier as we get older I'm afraid. 

 

Don 

[Eddie Fleming]

 

At one time I built chassis in a few hours; now it takes me weeks. 

[Jaeger Team]

Thanks, Don and Eddie.

[Jaeger Team]

First, a proper endbell that doesn't melt as soon as you look at it.
 
Here I don't want to mount the engine flush with the bottom of the chassis as we did in the sixties with the aim of lowering the rear axle to mount smaller diameter wheels, for example Asp ones. So I thought of this modification that fits very well into the engine support. (My friend Dario will approve; he is a purist collectionist.)
 

 

 

[Pablo]

That is awesome, Maurizio! Any help from USA you need I am here for you.

If you install a rubber band on the guide flag, I have the "Korrect" type.

 

I am here for you at all times

[Jaeger Team]

Thanks a lot Paul!

[Jaeger Team]

If I think of myself as a young boy in the frantic search for the lowest center of gravity, I considered that rear axle too high, and instead the Cox engineers had studied such an inclination of the engine that it passed the drivetarian test with all honours.

Here is the empirical demonstration...

 

[Lone Wolf]

Nice

 

Somehow this stuff lives on after 60 years. A testament to the care and quality that went into the original design.

 

That is actually a somewhat rare two-hole Super Cuc/Racha drop arm with the correct forward pin guide.

 

Missing one tab for the rubber band so it will not work as is.

 

Joe

[Jaeger Team]

Thanks, Joe.

 

Actually my mind is to use one of two guides shown on the top right in the first picture.

[Martin]

Hi Maurizio, flowing your build here. Have you raised the can end of the motor and or, lowered the rear axle? sorry its not quite clear to me what you did on the chassis to motor mod?

 

We raced them here in a vintage class 20 years ago now, but I remember I added lead in the chassis windows and ran a piece of fiber tape across the bottom of the chassis to limit moment.

 

Working slow gives more time to enjoy the journey   

[Jaeger Team]

Thanks, Martin. The motor is going to mount on the original supports.

[Jaeger Team]

Martin pointed out something to me which I immediately verified.
I was wrong.
Actually the motor, mounted on the chassis, is not originally inclined in such a way as to compensate for the difference between the plane of the driving axle and the plane of the rear axle.

[Jaeger Team]

First measurement I did without the cup so the motor was just a bit inclined... Eureka!

 

 

 

[Jaeger Team]

Therefore I don't know yet whether I will decide to lower the rear axle. My purist collectionist friend wouldn't really agree if I filed down the chassis to install the bearings lower...

For the moment I'm focusing on the motor...

 

[don.siegel]

We may be purists, but there were a million Cucurachas sold, so go ahead and file - as long as it's allowed by the rules. And the rules for Cuc Day are pretty liberal... 

 

Don 

[Jaeger Team]

Liberal...that's for sure Don 🙂
Maybe I could switch on bronze bearings machined for the purpose, thanks!

[Jaeger Team]

Also the can got a ball bearing.

Next step, glue the magnets with the JB Weld, but first you need to choose an arm that is not too much of a beast but not too much of a schoolgirl.

Note the shims that have almost evaporated due to corrosion...
 

 

[Bill from NH]

One could also use an angled tooth pinion. Those mesh okay with Cox & Parma crown gears in a hypoid arrangement.

[Jaeger Team]

Thanks for the advice, Bill!

[Jaeger Team]

Bill made me think.
The dilemma here is this: if, as Don advises, I lower the rear axle I will be able to fit a crown gear of a limited diameter and therefore I will need one of those Cox extra long pinions; if otherwise I leave the rear axle in the original position I will be able to fit say a 30 tooth crown gear this would probably allow me to use an angled pinion...
I have to do some testing because I don't yet know how long the motor shaft will be.

[Jaeger Team]

... for example, here we have a Parma crown gear 27 teeth, a modern Pro Slot 16D arm...

 

[Jaeger Team]

With a small piece of 800 grit sandpaper wrapped around the recessed shaft of a 6mm reamer. I'll enlarge the bearing holes a little... just enough for the bearings to line up well. I'm confident I could have a good gear mesh.
Pinion comes from back in the days.

 

 

[Jaeger Team]

I want to try to make this toy a racing car...
This is Pablo's idea to make the rear end bulletproof...

Attached Images

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[Martin]

That Pablo guy, pretty smart fellow. Sure knows how to build a slot car, that rear axle mod looks super strong