40 replies to this topic

[Jairus]

Probably only a few will kick in on this, but I like the idea.
It's one of the few projects during these last few months that I really can get behind.

Sadly, there are many other projects in front of it so do not expect a lot of daily progress.

But the plan is to stuff modern magnets and arm into a "C" can motor and build a 4.25 wb stock car in the 1970 - 71 style.
Unfortunately my experience has shown that about 50% of the motors I build turn out well.
So... to that end, I decided to build two motors.

The first a Mura with a  tagged gp20 arm.  Not sure who wound it.



The second, a Champion with a Camen tagged 27 arm.


Whatever sounds best, will be installed into a hand built chassis.

The body is a M.A.C. Torino Cobra Stock car body.  Never done one of those and mildly excited about the prospect.



The paint scheme at this point... probably like this.  
But like a girl, I tend to change my mind from time to time.

 

[SlotStox#53]

Superb idea! Both motors look and sound killer

Can't quite tell, is the Torino complete with squished roof? Either way, look forward to the build & finished car

Got a few bits including a suitable bodyshell to have a go, although building will be a good way off as operations are still suspended post Harvey

[Jaeger Team]

 

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[Bill from NH]

The Torino Cobra was introduced in 1969 with a streamlined nose for the high speed NASCAR tracks at Daytona & Talladega. It was built to compete with the winged Chrysler Motors cars.  Street model Fords were given that name in later years. I saw David Pearson run the #17 at a race in 1968. It was the most beautifully looking car there & finished 2nd to Petty.. After the race, we went out on the track for a look close up.

[Pablo]

GET OFF MY LAWN!!!

 

This is going to be super cool

[A. J. Hoyt]

I got to see that car race in person, too, at MIS! I was hooked!

 

Stock cars were so much more diverse looking and not just "wrapped sponsor blankets" back then. Plus, they looked recognizable to the real street car so a Ford was a Ford and a Dodge was a Dodge (even with their torsion bar suspensions). Now, they need headlight, tail light and grill wraps to make them look sort-of recognizable to the street car (until they line up next to an actual version of the street car).

 

Chevrolet omission was deliberate without being cruel - just look at the race results during that era. 'Nuff said.

 

I just broke out my parts to build a Retro-style chassis for my own Ford GT Mk IV using a Lancer repop (true to scale, not Truescale) body with an actual specific-and-accurate Ford GT Mk IV Lancer interior (from the 60's) I found on ePay. It will have working headlights and tail lights with pendulum-operated working brake lights. The chassis has been designed around tires that will be accurately sized with Mk IV correct wheel inserts (already have all these parts).

 

My tribute to Dan Gurney and A.J. Foyt in winning the '67 LeMans contest.

 

Looking forward to following your thread, Pablo.

 

Keep it in the slot (and preserve its beauty but know it wants to be driven),

 

AJ

[Foamy]

The unknown arm is a Camen Group 20 machine wound, early 70's. 10bux new i think. . .

[havlicek]

Two excellent possible ways to go Jairus, and all being equal with the setups, either one should provide serious muscle.  A side note, both arms show the coils spilling past the outside ends of the stack, something all but impossible to avoid with some winds because of how little room there was on those lams.  I had many of the Mura 20's  (*and the 20+) and they ran like the dickens, but the Camen is especially pretty.

[Jairus]

Thank you Dennis.  So both are Camen then.
I was pretty sure I bought it from Pro-Slot in a baggy with card many years ago through NCP.  But it was at least 10 years ago and the grey matter is not what it used to be.

No rest for the wicked.
Been working on artwork for Johnny Lightning with other projects waiting in the wings. 
I only started this thread to make my proposal for the project.
Thanks for all the support.

 

[Jairus]

Finished a slot car and Johnny Lightning and paint is drying on another body.... so.... built a couple motors this evening.

The Mura fell together.  Pretty much because the can bearing was toast and sounded bad once run up.
New bearing and now it's the stronger motor.

The Champion took a little longer sourcing out the correct end bell and hardware.  But it sounds pretty darned strong.  
And, better, it looks cooler than the Mura just because it's not the norm.
Tough choice.



Both are good strong motors and both will end up in nice cars.
But the question is, which will go into the Torino?

Wheels have been trued up.
Someone suggested I re-purpose some old wheels.  So that is what I did, soaking a set of orange rubber in lacquer thinner till the donut came off and then glued and trued these up to 1969 standards.   Continue to soak them with Trinity treatment to keep them soft.
Front wheels are repos from O'Keefe and Thigpen which replicate Associated items from the era.

 

[Pablo]

If the chassis is fairly heavy I'd go with the 20 and save the 27 for a lighter weight/more downforce/low profile body.

The 20 says "GET OFF MY LAWN". It's the sawed off side by side double barrel 12 gauge shotgun of the two arms.

It will push a heavy chassis better than the 27. Just my theory

[Jairus]

Well, it's been fifteen months since an update on this project.  I did get some work done tho.  Found another nice motor (Gp 20 Paul) and have no idea where the Associated wheels with the orange rubber went.
But I did glue and true up some vintage blue rubber on a set of Parma "look-alikes" that will fit the paint scheme better.
Also built a proper interior. 

 

 

This always happens to me when I finish and mail off a project to a customer.
I spend a day or two going through the cigar boxes of projects breaking down those that won't ever get finished and maybe even working on something old and forgotten using fresh eyes.

Tomorrow, back to the drawing board.  Happy Sunday Slotters!

[Pablo]

      

[Jairus]

Change of plans.  (slightly)
Decided this morning to dump the "C" can's for a more vintage looking Mura B motor installed in a rare one piece Simco steel center section designed for right hand drive. 
The motor I picked is a Dave Bloom milled B can which is just about as rare as the steel center section and both appeared on the scene about the same time as the MAC '69 Torino Cobra body so it's a nobrainer.
That time period would be 1970 or early '71.  Issues of Model Car Science were replete with B-can motor building articles so they were popular, if maybe not the best on the market.

 

Taking inspiration from Mike Stuebe's winning car from Sept. 1969 Model Car Science but setting the wheel base at a more Stocker length of 4 3/8", I finally have the jig set up! (Running a B motor by the way!)

 

 

As Mike did with his winning car, he ran the motor can drive on the right side of the chassis.  This baffled me for a while till I realized he wound his own arms so.... duh, he wound a CW timed arm.  Easy huh?
I only have one, an old CW arm that looks by the balancing marks to be either Mura or Lenz wound.  Com is in good shape but the shafts have been cut down MAKING this one a can driver.
As I mentioned, it all fell together eventually.
Below: endbell notched for frame clearance.
 

 

Arm is below.
 

Well, at least I have direction now.
Stay tuned.

[Jairus]

Okay, just a few words about the Bloom milled can.  Because I think this is significant.
And... wire wrapping the uprights is boring so...

On the left is the standard late model "B" can and on the right the milled "B" can.
Standard measures right about .040 -.041 thickness steel formed and folded, then spot-welded into a solid unit.
The milled can starts out same thickness but someone milled the top and bottom outside to .030.  And they radial milled arm clearance inside leaving .015 thickness down the center.
Didn't weigh the cans but they feel different in the hand.
This is a trick that Model Car Science suggests in the November '70 issue.  However they suggest thinning the top and bottom to .020.
Me, I am lazy and don't want to destroy the original finish too much other than the cuts already made so... I call it done.
MCS calls the thinned can a 20-40, so that must have been a thing back then and available by somebody.  Cool era no?

[Bill from NH]

For awhile, Mura sold B-cans milled top & bottom, but without the interior milling. I have one, I think with a rectangular hole, so it would be a later can. Mura tried a lot of different things to make the B-can competitive & run cooler. One of my then wing car friends, Dan Oneill, even build a full sidewinder using a B-can with lots of grinding. I built a Grp. 20 setup using a milled Champion C-can. A print shop friend milled the top & bottom to .020, I turned the sides to the same thickness. That setup never worked right, but it ran hotter than it should have. I still have it packed away somewhere.

[Jairus]

Happy Sunday morning! (My favorite day of the week)

Last night late I finished up the center section and then began playing with gears.

 

The current gear set is a 9/42 using a FAAS ring gear.  Motor is set back as far as it can go and the ratio is about four and a half to one.  Pretty high ratio.
Ed Lewis ran a 9/46 in his Sidewinder back in 1970 using the same wind as this arm  so... I need to start looking for a 46t gear.

Also going to order a straight cut 9t pinion as that angled ARP pinion is not really vintage... but ohhhh how smooth is the gear mesh!!!!  Better than sex in my opinion.

[Jaeger Team]

For awhile, Mura sold B-cans milled top & bottom, but without the interior milling. I have one, I think with a rectangular hole, so it would be a later can. Mura tried a lot of different things to make the B-can competitive & run cooler. One of my then wing car friends, Dan Oneill, even build a full sidewinder using a B-can with lots of grinding. I built a Grp. 20 setup using a milled Champion C-can. A print shop friend milled the top & bottom to .020, I turned the sides to the same thickness. That setup never worked right, but it ran hotter than it should have. I still have it packed away somewhere.

at that time a group of guys from Palermo (completely crazy and slot addict) threw away the original cans and rebuilt them in aluminum ..

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[Bill from NH]

How did these aluminum B-cans run? Do you have any idea what they ran for magnets & airgaps?

 

Jairus, we use to break in Faas brass spurs using a lightweight grease, such as Lubriplate or Camen's "Grease-it" green grease. Set the mesh moderately tight in the spur's high(tight) spot, apply grease, & run them in at 3 or 4 volts for 2-5 minutes. The spinning pinion will distribute the grease  to all the spur's teeth.

 

Straight-cut steel pinions will create a slight burr on the outside face of the spur. That won't hurt anything. I use to reface my old spurs by cutting off the burr & lightly brushing the teeth with a SS braid brush. These refaced gears weren't as quiet as when new, but they worked great when practicing.

[Jaeger Team]

[quote name="Bill from NH" post="751361" timestamp="1559504928"]How did these aluminum B-cans run? Do you have any idea what they ran for magnets & airgaps?
 
Same magnets and airgap as they come out from production. The alluminum can actually lowered the magnetic field (and weight, of course) making that car (Mini Can-Am made by Mini Dream) more driveable.

[Don Weaver]

Rick Thompson, who has since passed away, put some jewelers paste on his gears once but no one told him that it only took a few seconds to break the gear in.  When he stopped to check it he only had a round disk left where the teeth had been.  Miss ole Rick, he was a good dude.

 

Don

[Jairus]

Meanwhile, back at the Ranch...

...Jairus was hard at work building up a guide tongue and plumber rails in the 1969-70 style.
The popularity of the full width front bumper may not have shown up till later, but PdL started using them about this time so it's not totally out of the realm.
.055 rod was used for the plumber rails and don't worry, I won't be soldering the brass tube to them full length.  Learned that lesson years ago....

 

Time to make a plumber frame.

 

 

[Jairus]

Finally the chassis is one piece with lots of movement. (No limiters installed yet)
Next up after lunch is to clean and shine her up some.
No tumbler this time as that's being used to polish up a lot of 30-06 shells.

 

 

Historically the "L" drop arm hinges were an early 1971 item.  Spent a lot of time last evening going through magazines and Slot Racing news reports to discover when the full width front bumper showed up.
Seems it didn't till 1972, so that is going to get trimmed.

[Pablo]

Perfect. That monster is gonna hammer the corners hard   

 

Get off my lawn!!! 

 

 

 

[Jairus]

Still making progress.  A few clearance problems and the center section is really wide!  
The final chassis ended up being three and a quarter wide!  Great for modern day, but back in 1970... 
So I cut 1/16" off each pan, trimmed the bumpers and basically been working on clearances with the motor.


STILL LOOKING FOR A: 64pitch 46t spur gear... FASS preferred.



Didn't get much done yesterday.
Had to work on the car...

 

 

... where I replaced the speedo head so I could finally have a working speedo.
Tested it on Glen Creek Rd. where they have a radar speed reader and the new(er) speedo is spot on!
I even changed the odometer to match the original.  Not that it matters much, hasn't recorded a mile in 8 years!