117 replies to this topic

[Pablo]

Thanks Jairus,

That is one of my main thoughts; maybe the huge, soft rubber is providing way too much grip way too fast. 1 inch of soft rubber has a lot a centripetal force. (Or, is it, centrifugal ?) Perhaps too much soft sponge being spun at hi revs.
Anyway, thanks for caring, I will dig into it Monday.......check the axle, etc.

Gotta bring home some more bacon tomorrow to pay the bills

[dc-65x]

Hi Pablo,

My R&C Team Russkit full sidewinder bounces down the straights too . I've tried everything in the frame, bearing and axle area to fix it to no avail. It has big TALL modern foam tires and a powerful motor too . Bummer.....

[Pablo]

Larger OD wheels may be the ticket.....more wheel, less foam......

[Tex]

Is the motor VERY powerful? Is the rubber pretty soft? If so, I wonder if the motor could be overpowering the rubber, literally "folding" the rubber as it spins the tires(?).

[Bill from NH]

Larger OD wheels may be the ticket.....more wheel, less foam......

HRE use to have some gigantic hubs when they made "Big Daddies," or whatever they were called.

[Horsepower]

I know this chassis is a little heavy but maybe a small amount of stick-on lead just ahead of the back wheels would help?

[Jairus]

Actually, Gary might be onto something. This chassis is pretty light! Weight is an easy add for testing P!
Overall some good ideas here to try. You also might try some rubber and silicone tires just for fun too.

[tonyp]

I agree too much traction. Today's tracks and tires produce bite unheard of when these cars were new. Even the foam tires had very little grip compared to what we have today. Try some hard stuff like wonder rubber....

[Pablo]

Is the motor VERY powerful? Is the rubber pretty soft? If so, I wonder if the motor could be overpowering the rubber, literally "folding" the rubber as it spins the tires(?).

Yes and yes, Tex. I think you may be right.

I know this chassis is a little heavy

Actually, Gary, it is aluminum, and it only weighs about 120 grams total, about the same as an IRRA stock car.

I agree too much traction

Thanks Tony.

Thanks everybody for the support, I will fix this glitch

Since I have no means to test the car without a 5 hour round trip drive, I cannot make small changes. I have to make big changes, and I have to get it right, preferably sometime this year . So, with the above intel considered, I am going to "swing for the fences" and change most of the drivetrain parts. I may change wheels to something bigger OD, find some harder rubber, go to a setscrew axle, etc. The nylatron Cox spur stays, thanks Gary, it works perfect and I know it's not a gear issue. Maybe these Riggen Magoo's Super Slicks are the answer ?

[havlicek]

Really nice car there Pablo! I agree with what the others are saying about traction. Since that big old Mabuchi weighs a lot, it's probably adding to the bite. Strong 36Ds can be a real handfull at the track because even with the right gearing for the track and power, their weight can change the whole traction equation. I remember Philippe posting a picture a long time ago of an ULTRA Sweet Champion 36D sidewinder rewind that even he said required a lot of concentration to drive well. It may also be that handling characteristic is just something that has to be lived with, since Rick seems to be saying his does something similar also. Of course, the controller could be adding to this, got a Parma turbo with no bells and whistles handy?

-john

[Bill from NH]

Pablo, are you running threaded wheels & axles? They don't run as true as a straight axle & set screw wheels, if you are.

[Pablo]

John, my DiFalco has the ability to make the sensitivity very soft. The smoothness lives inside that car, and I am going to find it.

Bill, there you go, reading my mind again. That was part of my "swing for the fences" plan

[tonyp]

I think we all from time to time lose sight as to how crappy this stuff actually ran when it was new. All the stuff was slow as hell around the corners. You simply went fast down the straights and tip toed around the corners. Until people started scratch building you could win a weekly race at our raceway with just about anything if you could drive with out falling off. It was all horsepower and staying on. Once the good foam tires and Blue-Goo came out it all started to change.

[Pablo]

Interesting observation, and good point, Tony. I appreciate all the knowledge base here on Slotblog, especially priceless insight such as this into the history of slot car evolution.

On the other hand, I'm bound and determined to make this car smooth. I know it can be done.

Paint is done. After much knashing of teeth due to my inexperience with purple paints, I think it came out nice.

[James Wendel]

Hey Pablo !

Lookin' good... I really like the purple on a Cheetah bod. Just one question:

WHERE did you get the "Mr Horsepower" decals ???? I had a set from a '60s kit, but they disintegrated when I tried to use them.

I REALLY want to find more.

[Pablo]

Thanks, James, for the compliment.
I am very sorry, I don't remember where I got those. I do not keep good records of where I get my decals.
I keep my eyes open, and I get them "Catch as catch can" style. Slotblog, Ebay, etc.
For me, motors, chassis, bodies, mechanical parts, are all parts I keep good records on. Unfortunately, I don't keep records on decals. Sorry.

[dc-65x]

Hi Pablo,

Your "Purple People Eater" looks great .



A thought on the tire "problem". Here's a link to an Ebay seller that makes really good urethane tires both modern and vintage repops. They can be glued to the rims with flowable silicone windshield adhesive and ground true on a Hudy tire grinder:

Paul's Slot Car Shop

They don't hookup as well as modern foam but better than vintage German sponge. I bet they would work better than the Riggen's and not bounce.

Just a thought..........

[Pablo]

Thank You, Sir dc-65x.

I love choices.

Tomorrow is a new day

[Bill from NH]

That looks likes a factory paint job, Pablo. Nice work! What shade of purple did you end up using? Be sure to tell Tom to avoid hard crashes!

[Pablo]

Model Master Acrylic 4650 Grape Pearl. Thanks for asking

[havlicek]

I think we all from time to time lose sight as to how crappy this stuff actually ran when it was new. All the stuff was slow as hell around the corners. You simply went fast down the straights and tip toed around the corners.

...ah the good old days!

-john

[ShootinSparks]

Kudos... that is a sweet build, Paul... I love the purple and the white lower valence panels... that is definitely in the spirit of the times and has the "feel" of a 60's vintage full-size racer as well as a vintage slotter.

And the double Mobil pegasus motif is the crowning touch!

[mcseitz]

Just wanted to add my compliments on the build. The decal application and spacing looks just like a car from that era. You must have channeled your inner 12 year-old perspective on that.

[Pablo]

Thanks guys !

The Jairus interior really adds a lot of class:

[Pablo]

The spots where the chassis form fits the body have been reinforced.
Now it's time to fix the hopping problem.
I ditched the threaded axle and wheels.

What I have here in front of me is a kit car that is incomplete. The original (Thanks Philippe de Lespinay) http://slotblog.net/...yclone-avenger/
was a can drive car where the endbell was screwed into the bracket, the can end of the motor was secured with a custom "clip", and the pinion drove a big threaded spur. Worked fine, BUT, my problems are: I don't have the clip, my motor is endbell drive versus can drive, I don't have a threaded spur of the proper pitch and OD to mate with the pinion, I don't have the correct pinion, and nothing aligns or measures correctly. This is why I am the man for this job. I improvise, overcome, adapt. I will make it work, and it will work well. But it ain't easy, and it takes extra effort. The threaded drivetrain was all wasted today. The big donuts, gone. The axle and vintage Mila Miglia wheels, in the trash. After you put threadlocker on small parts, there is no going back.

I worked with my dc-65x math tonight, and found one option that will work.
JK plastic .600 OD 1/8 hubs. Width cut down from about .800 to about .530.
JK donuts.



The result would be a pair of JK plastic hubs with modern soft rubber, 3.250 rear track width. I think it will work. I wonder if Duffy is listening ? Note, the photo shows .475 OD JK plastic rims. The ones I ordered tonight will be .600 OD. Too bad they don't have .675

This is a real brain teaser......if anybody has a brighter idea, I'm all ears.....