72 replies to this topic

[Jairus]

After the "year of love" that 1967 had provided... '68 was a very turbulent year.
Vietnam ramped up with the "Tet Offensive" and the "My Lai" massacre, we lost our first nuclear sub, "2001 a Space Odyssey" was released in the theater, Czechoslovakia was invaded by the Russians, Robert F. Kennedy and Martin Luther King were shot and killed. (whew!)

On the hobby front the model car industry was still going great guns while the slot car industry began seeing a down-turn with tracks starting to close because of inactivity. Mostly due to the boomer generation moving on to adulthood (cars and girls).

Slot Racing professionally had suffered a revolt of it's own.

The innovation of the "Anglewinder",  just a few months previous, had builders on in a crash 'trial and error' program to seen just what chassis version to build in order to make these table top machines go even faster.

 

The months April, May and June were before the plumber chassis was invented... but well into the tilting pans and motor box era. And that is where I want to venture into with this build.

Not a replica per se... just an exercise in fun for a change following along with the innovators of that early era.

 

Most popular bits used back at the time are shown:

Re-popped Lola T70 spyder for a body
Cukras/Mura "A" can for power
Riggen wheels for grip with new rubber
Cox for a guide
Cobra for gears (not sold on that just yet and might go Weldun or Cox)



Lots of race reports and chassis build articles featured in later '68 Car Model mags show the variation in pan, tongue and rail designs.  So... I am pretty open to what was used. Some winners like John Cukras below ran little more than an earlier 3-rail jaildoor anglewinder chassis to win. While others  on the east coast were using 4 rail (brass and music wire mix). (See Tony Przybylowiez "Team Nutley's Winning Easter Chassis" article in Oct. '68 CM)

 

I sort of like the simplicity of the Cukras chassis and will probably go that route.

The key to this project is the motor of course.

It's a piece I've been working on for years.

A replica (no... not original Pdl) of an original first gen Cukras/Mura motor built with all original parts!

Arm features an untied com and came out of an early Mura "A" can.

Can and end bell also early "A" with no can mounting holes.
Mura Magnets of course.

Only thing I added were the shunt wires.
Thanks to John Cukras for the correct unused can decal.



Sings mighty sweetly and might be a gernade. But will suffice for this project.

Only thing I've done regarding a chassis is bending a motor box and cutting a drop arm.
But the day is open.... 

[Gator Bob]

Great opening post !

 

I love the way you painted the can and I'm sure this car will be awesome.

[SlotStox#53]

Wow what a collection on parts for a super cool project!! Simply love that Cukras motor

Very much look forward to seeing this one come to life , really like the simple design of Johns jaildoor anglewinder ..

Build on !

[Pablo]

I'm going to love this for sure

 

P.S. Jairus, when you apply a few Volts to test the drivetrain, I'm sure you will be thinking of this: Those Cobra gears do not mesh.

That is why they are all over the internet. Garbage. Please, for me, just ensure a Cox or a Weldun will fit in whatever nest you build for it.  That way it will be easy to swap.

[Dennis David]

I love these recreation/restorations.

[Hworth08]

Pretty fair chance the Cukras chassis in the article was a converted in-line. Many of the first angle-winders were convertees.

 

The Cukras really needs a white endbell with pent roof brush holders. That endbell was an important advancement for Mura and the key difference between the very popular #444 Magnum 1000, especially the later 444s that had the .007 arms. But some of the early Flower Power motors might have had gray endbells...if that's what was in the parts bucket that day.

[Jairus]

Don,  That's the later "Cukras" pink can motor you are thinking about.  
Collecting parts for one of those too btw.

[dc-65x]

Great project Jairus.

 

Don, here's a reference for the Cukras motors:

 

Mura "John Cukras Signature" motors

 

Jairus, where did you get the foil Cukras sticker?

[SlotStox#53]

Don't know which one Jairus mentioned but said John provided an unused can decal don't know if that was the flower or the foil decal.

[dc-65x]

Oh, I see it now. From the man himself! Cool

[Hworth08]

Guess I'm getting too old to correctly remember things that happened that long ago. I do remember the first time I saw one of the Mura "fogged" motor though. It was already in a car and I thought that sucker had got so hot it had scorched the paint!

[SlotStox#53]

Jairus , did you paint the can? Or were you able to find a "Cukras" A can wearing it's original paint? Either way that motor just looks like it's doing 100 just sitting there

[Jairus]

Yes I painted the can Paul.  Since I have seen more than a half dozen versions of this multi-color motor can painted... I simply picked one and went with it.
Pablo... found a Cox gear that will fit the bill sir!   

[SlotStox#53]

Excellent job on the can, having looked at several pictures of the fogged paint Cukras motors it certainly is the "real deal"   One day will have to try and collect the parts for just such a motor or maybe the Pink Cukras motor that Rick did for his 6 wheeler

[TSR]

John Cukras still has some of the old "Mura Cukras" stickers. It helps when attempting a nice restoration or making a copy of a car long disappeared.

Just to make it clear for Don, there were two distinct generations of Mura-Cukras. The first used cans painted in fogged colors (Ron Mura told me personally that he painted those himself!) and they exist in several colors:

-Gold with black fogging (longitudinally)

-Gold with black fogging (sideways)

-Silver with yellow fogging (longitudinally)

-Yellow with silver fogging (longitudinally)
 

More colors may exist, but few of these motors survived because they were effectively hand grenades.
Why? Two simple issues:

1/ wires were soldered to comm.

2/ wires were not tied between poles and comm.

When hot, the poorly retained brush holders began moving in the over heated endbell, generating more heat than the solder could take. The solder melted and the motor threw its wires with extremely spectacular effect.

Ron Mura called John Cukras for help after John refused to race the stock motors, and George Mura accepted the recommendations of John and Pete Zimmerman, bought a welder and redesigned the endbell with pent-roof holders, something used by Champion two full years earlier...

The new welded arms were also tied and that resolved most of the issues. The new motors had a white phenolic plastic endbell and pink cans, later there were some black cans, then purple, then white. I do not know in which order they were available, and I do not believe that anyone knows today.

 

Of the early motors in fogged colors, very few have survived. Of the second generation, lots of pink ones have survived. The purple and black motors are the hardest to find, the pink the easiest.

 

[SlotStox#53]

Loving the different color combos on the fogged 1st Gen cans ,those flower decals really go well with it. Definitely keep my eyes open for parts in the slim chance of sometime putting one of these babies together. Thanks for the pics Philippe & thanks in advance Jairus for deciding to build this car & using that motor

[Pablo]

Jairus, I'm glad you found a Cox. If you didn't have one, I probably did.
In a twisted kind of way I was hoping you would find the lousy mesh on that Cobra to be true.
The ones I have could be knockoffs ? Hard to believe a real Cobra gear back in the day would be practically worthless.
Anyway, the Cox is the answer. <G>

[Jairus]

There are two different runs of Cobra gears that I have noticed.  Early ones are dark grey and seem to be good as I have a number of them found in rolling chassis via eBay or came in a Cobra package.
Then there are the black ones.... which I have never seen in a package and suspect they were dumped on eBay long after the boom ended. 
Most of those tend to wobble or were cast out of true.
 

Regardless... the Cox is a 36t which provides a 4.5 to 1 ratio.
But I will never "Race" this car.  It's just for fun!

[Hworth08]

Thanks Philippe!

Actually I don't remember the fogged cans as being Cukras motors. Being in the southeast we knew of the Champion team members but a west coaster with name we didn't know how to pronounce... I do remember the pink signature motor though. That motor was $7 or 8 higher than a Magnum 1000. The shop owner had both motors, my brother and I compared them an hour or so before choosing the 1000 thinking the signature was a marketing ploy.

That 1000 motor with a Cobra 5 rail in-line frame and McLaren 6 body was the fastest local car a month or two before the anglewinders arrivied. The frame's gone but I still have the motor.

[dc-65x]

....I was hoping you would find the lousy mesh on that Cobra to be true.
Hard to believe a real Cobra gear back in the day would be practically worthless....

 

It's all in the "Korrect" pinion gear Pablo. When you find a pinion that the Cobra spur likes they work fine. Unfortunately, most of the pinions I have, both new and vintage, don't like the Cobra spur. I try to avoid the Cobra spur gear too but they are the ones that are most available, unlike the Cox.

 

Gears are a complex subject. There is more to "gearing" than just the pitch and the number of teeth. Not all 48P or 64P gears are the same. I've got lots of different 48P pinions from new to those made in the 1960's. If you look at them closely you'll see a different "gear tooth forms"  which is, more or less, the shape of the gear tooth. Some are "roundy" and some are more "pointy".

 

When I'm using a Cobra spur I'll try pinions of different tooth forms and try to find one that meshes well. The Cox on the other hand, usually meshes beautifully. You just need to find one that the hub is on straight and true . I remember buying a new full box of Cox 34T spurs thinking I'd really scored. Every one of the suckers wobbled like a drunk staggering out of a bar at closing time

 

There are two different runs of Cobra gears that I have noticed.  Early ones are dark grey and seem to be good........Then there are the black ones....

 

I haven't tried the "black" Cobra gears. All the ones I have I've gotten have been from pretty recent REH purchases and they have all been grey.

 

From the anglewinder beginning in early 1968 the Cox spur gear took over from the first used aluminum 64P Weldun and was used well into the 1970's. Look at Lee Gilbert's famous CM article and he's using a Cox years after the Fass 64P gears came out. I think PdL has commented on the Cox out lasting the Fass gears in the 70's too.

 

I think the Cox gears are hard to find because they worked so well they were just used up.

 

Sorry for the babbling .

 

Onward Jairus

[Steve Okeefe]

Jairus,

 

Since you are not building a replica, but a period-correct original design, you have a great deal of freedom when it comes to the chassis design, especially the center section.  In June 1968 the field was still wide open, as the various pro builders were still sorting out what they thought worked best.

 

Have you decided to go with a motor-box, a full-rail design, or something else?

[Jairus]

Steve,

Thinking of a full motor box with 4 brass rails.
Race reports were pretty standard with such designs.

What I have noticed is that most builders used in-line motor brackets cut to make anglewinder motor brackets. So... my question to you dear historian Steve... what should I use for a car built between the months of April to June? Were adjustable motor brackets available in hobby shops during those three months?

[dc-65x]

Hi Jairus,
 
If it would help, I've just looked in Model Car Journal June 6, 1968 and there are ads from Associated and Mini Wheels for "sidewinder motor brackets set at a 20 degree angle and allows for adjustable gearing".
 
So these are motor brackets with a built in axle bracket that can be cut up for your build like so:
 

I saw a beautiful Mike Steube built mid 1968 pro car on Ebay and I knew I had to build my own version. The car ended up with LASCM and was beautifully restored by PdL. Photo courtesy of Philippe de Lespinay:



Here's the link to its restoration:

E-Payoff, or How we found this wonderful Steube car

Philippe also took this picture to help us wannabe's build our own version. Photo courtesy of Philippe de Lespinay:



I printed this out and used my measurement of the ruler to establish a scaling factor. Then I could measure other things on the picture, multiply them by the scaling factor and get a rough idea of what size things are on the real chassis. A rough idea is fine for this project as I am not trying to clone Mike's car. Rather I'm doing what I did back in the day.....plagiarize other peoples ideas . Actually there is just something about the way some cars look that sparks my interest. I don't have a first generation angle winder to run in my shop car box. I wanted to see difference in performance that caused the Pros to dump inlines so quickly.

I'm using an Associated motor bracket and drop arm that Mike may have also used. His drop arm is for the Cox guide and mine is for the Dynamic Low Profile guide that was also used in this time period. Mike even used one to win the 5th LA Championship race in Oct 1968:



I narrowed the drop arm to 7/8" and cut the axle bracket off the motor bracket:

[Steve Okeefe]

Jairus,

 

Generally a bit too early, but there were a few adjustable motor brackets; Rick has already pointed them out.  Most of the manufacturers however hadn't caught up yet.  Personally, I would use a cut-up inline bracket, but then I'm old school.

 

A good choice for an inline bracket to cut up for this build would be a (currently available - PCH Parts Express) REHCo #3000.

 

Four brass main rails with simple uprights to the front axle is a good choice.  The motor-box should of course be piano wire.  Builders were commonly either wrapping the outside rails around the motor-box or jogging them up and over the top of the motor-box.  Inside rails were commonly turned inward and soldered to the motor-box.

 

A few builders would simply butt the outside rail up against the motor-box and add piano wire braces over the top of the main-rail to motor-box joint.  The brass strap over the top was not yet widely used (we're speaking of a matter of weeks here) , but would be later on.

[Jairus]

Went through all my stuff and used up all those REH brackets.  A little shocked I can tell you. Almost tore apart another old chassis just for the bracket... but something said patience.

So made an order to PCH.  
In the mean time I can build the tongue and cut some brass tubing.

Thank you all for the very helpful information. Got lots coming in from all parts of the hobby!  Thank you!

[Jairus]

Here are three examples of cars ran during the 1968 Arco 33 Nationals held at Tom Thumb raceways May 18th.
These give us a peek at the variation that was going on during those transition months.
 

 

The first built by Bob Emott.
Note that Steve is right, that Bob started out right of the gate building full rail angle-winder cars.

 

 

 

The next two were built by two more very well known guys in the biz... Steube and Cukras!

 

 

With this in mind I went ahead and made my drop arm and motor bracket.

[SlotStox#53]

Certainly were a lot of chassis differences in the early stages ,great to see all the different designs & ways round the anglewinder that builders took.

Bob certainly did go all out right away, really like the full rail chassis

Looking good so far Jairus

[Hworth08]

Certainly were a lot of chassis differences in the early stages ,

Everyone was having a lot of trouble with bouncing and wheel hopping. My first anglewinder had the bearing tube welded to the can like Gene Husting. A smooth running car. Next used a motor box and the problems began.

Finally we figured out to use the simple little L-brace between the axle tube and motor that completely solved the problem. Course we did worry if we would go directly to hay-dees for soldering on the can!

[S.O. Watt]

Here are three examples of cars ran during the 1968 Arco 33 Nationals held at Tom Thumb raceways May 18th
 
 
The next two were built by two more very well known guys in the biz... Steube and Cukras!

 
 img=http://images41.fotk...IMG_1399-vi.jpg]

I believe that these two frames probably pre date the Emott. These look like some of the frames that John and Mike made into anglewinders from donor inlines in April just prior to the debut race at Classic. The construction details I believe support this. With Bruce now listed as the owner of the Mike S frame, that leads me to believe Mike sold him this car after the April race. Pretty common for Bruce to purchase the winners/used cars back then, especially from Mike.

The Cox spur gears were finally supplanted by the Faas gears as the preferred by the end of '70. The quality had gotten so bad that one could check ten 34t Cox gears and find maybe two that didn't have extreme wobble and were raceable.

[Steve Okeefe]

Jairus,

 

Yikes!  You don't waste any time fooling around!  

 

I worked up a partial chassis drawing showing an example of how the motor-box and main rails could go together:

 

 

Queing from your photo I made the drop arm in the drawing 3/4" wide and the motor-box wide enough to accommodate a Mura "A" can motor.  The center section in the drawing is unusually wide for May 1968 (except for Steube, most builders were still crowding the main rails in towards the drop arm).  I did this so you can clearly see two things:

 

1. How important it is to keep at least the gear-side front corner of the motor-box at or near the one-quarter chassis width point.  The opposite side one-quarter chassis width point can fall at its associated front corner or somewhere along the edge of the motor-box.  Doing this enhances the symmetry of the chassis, helping all the other parts fit better, and also adds to the aesthetic appeal.

 

2. How narrowing the center section will force the rails that wrap around the wide motor-box into a taper in order to match up with the narrower main rails.  This causes the rear side-pan hinge tubes to be pushed way forward.  You can clearly see this in the Emott chassis photo you posted.  Pushing the side pan hinges forward leaves a lot of the back end of the side pans (and the body that is mounted to them) hanging out in the breeze.

 

Narrow center sections with parallel rails were still a typical feature in May 1968, but the photo of the Steube chassis shows that some builders were already spreading out the rails, making the center sections wider, and enjoying the benefits.  A near-ideal center section width is between 1-1/2" and 1-5/8".  In the drawing I posted the center section is 1-5/8" wide.  Bob Emott wanted to keep the chassis narrow at the point where the front axle attaches, so he built his center sections with non-parallel rails, tapering smoothly from back to front.

[SlotStox#53]

You don't hang around either Steve! That detail drawing is coming along nicely great information on all the differences with the rails & center sections.

The drawing will go with all the others for reference when looking at what cars to build.

[Pablo]

The fog paint on the motor just looks SO naturally beautiful with the brass.  Once again, the bar is raised...... gives me goose bumps.....

[Steve Okeefe]

Jairus,

 

After I posted that quick drawing yesterday I realized I had ended up describing something that I wasn't showing.  So, given 24 hours I've re-done my drawings so they are more comprehensive.

 

For the wide set main rails (1-5/8" wide center section), here's how far back the rear side pan hinge tubes can be located (this could be considered the "gold standard"):

 

 

If you crowd the main rails together towards the drop arm (giving you a 1-1/4" wide center section), the rear side pan hinge tubes must be pushed far forward, in this case all the way to the drop arm hinge.  This is an extreme example to illustrate my point; I doubt any pro builder would actually construct a chassis this way:

 

 

Most builders would (and many did) add extra bends in the outside main rails, jogging them to get that rear side pan hinge mount farther back.  Introducing extra bends complicates the build, and the closer together those bends are the harder it is to get them right:

 

 

There are of course several other ways to deal with this dilemma.  In the wide set example, the rails are spaced at 1/16"; it would be just as easy to space them at 1/32" (or some combination of 1/16" and 1/32").  That way they appear to be close in but the outside rail would be far enough out that the jog required would be much smaller and simpler (simpler is always better)  Note in this example, the center section is 1-1/2" wide:

 

 

Another way to locate the rails farther out would be to add a space between the drop arm and the inner rail.  You couild also use a wider (7/8") drop arm.

 

Lastly, you could taper the whole center section back-to-front so that the outside rails remain completely straight from the motor-box to the front axle on both sides (same as the wide set main rail example above), allowing you to locate the side pan hinge tubes anywhere you like (that's what Bob Emott did).

 

Anyway, all of this is just babble from an old chassis geek.     Hope you find it useful. 

[Jairus]

Wow! You put a lot of thought into this and the first illustration is what I was going with originally.... albeit with 1/4" outside pans and brass* inside rails. But that is very close to the plan Steve, very nice!

Working on some box-art illustration at the moment... but this afternoon I believe I can get jiggy on the chassis again!   

 

 

* When I say brass... I mean hard bronze welding rod instead of that soft K&S stuff.

[Hworth08]

 

 

 

* When I say brass... I mean hard bronze welding rod instead of that soft K&S stuff.

 

The K&S brass is soft, to make it easy for hobbyist to bend. Bare brass (non-coated) brazing rod is between bronze and K&S. The brazing rod is LOT cheaper, 32 or 33 three foot lengths cost $12 to 15.

[Pablo]

I tried some once.  Must have been the wrong stuff, because it was very brittle. Bend it a second time and it snaps.

[Jairus]

Yeah, that's the stuff! 
More flexable than soft brass, holds up to a crash and ... well, that's all I got.

All jigged up on the threshing room floor.
Now gotta figure out how to attach to the front axle? Hmmmmmm? 

 

The standard was to bend the front wires up towards the axle tube pretty much like they did since '67.

Strong and simply.

However Emott suggests with his chassis build using two "U" wires, and there-by promoting a bad and weak mounting idea used for a year or more until the "L" bracket idea.  Tony P also backs up this design in his chassis building article. But then, that article didn't come out till October so....
 

Guess I'll go the old school route since most of the cars shown built during April, May and June seemed to use that idea.

[dc-65x]

HOLY SMOKES!

 

Now that's a "loved" Rick's Jig for sure! The stories I bet it could tell

[Jairus]

I know... so embarrassed to show it. 

[Pablo]

That is what is so nice about all those holes....you can avoid burn spots like re-routing a highway trip.

[gascarnut]

I know... so embarrassed to show it. 

And here was I thinking "that looks just like my jig"...

[Steve Okeefe]

Jairus,

 

You wrote: "However Emott suggests with his chassis build using two "U" wires, and there-by promoting a bad and weak mounting idea used for a year or more until the "L" bracket idea. Tony P also backs up this design in his chassis building article. But then, that article didn't come out till October so...."

 

Yes but...

 

The chassis was built in May of 1968 (says so right in the article), so you're good to go with the drop axle front end if you want to.

 

With four rails on each side, you're going to have 16 separate solder joints holding the front axle mount on.  Somehow I don't think it's going to come off in a crash... 

[Hworth08]

The two "U" pieces with a 5/32nds tube such as the Emott frame in post 26 gained immediate popularity when it was introduced. A lot easier to build than bending the rails and very strong.

 

Another feature was giving a place to butt the guide mount against. With increased speeds breaking the solder joint holding the drop arm was becoming a problem.

 

IIRC we started using that front end arrangement on in-line frames.

[Jairus]

I beg to differ Don.
For a time between 2006 and 2010 I was buying up lots of those "Kit" chassis just for the Mura "A" motors.  And each and every one showed a broken solder joint somewhere holding the front axle tube.  Most are in storage now or I would have posted a "rogues gallery" of poor building in conjunction with this car that I'm building.  

I agree with you that it gained immediate popularity because it was indeed easier to build. But disagree with the "very strong" statement.

HEY! The iron is hot!

[Jairus]

Here we are so far.
3 7/8" WB and set for a 3" track width with legal 3/4" front and 7/8" rear tire diameter.
Hanging of the "sloppy sam mounts" next, while waiting on PCH to deliver the needed period motor bracket.


On a completely different subject.... Victor emailed me this pic asking if I would like to use a little different body for this project.
Still a Lola... but from a different manufacturer (on the left) and has slightly different details than the normal T.S. Lola T70 we are used to.
Of course I said YES!!!!
(Anyone want to identify the original maker of this body?)

Everybody HAPPY HAPPY HAPPY!

[dc-65x]

Looks like the earlier generation of Dynamic Lola T70 with the exhaust pipes showing behind the Weber carbs. We call it the "short nose Lola" in our little word.

 

It sure would be nice to have these available as they are the Korrect version for Pro inlines.

[SlotStox#53]

Ooo love the look of that Lola , always nice to have more bodies to choose from

[dc-65x]

Jairus, you might have some trouble with spur gear clearance with the "short nose" version. See how "long nose" version on the right has wider bulges for gear and tire clearance?

[endbelldrive]

It would be nice to have extra depth on the rocker panels (drop the bottom trim line an 1/8" of an inch...or do away with it altogether   ) so we can raise the back end for motor, gear and tire clearance.

[Jairus]

Just got home after a full day of work... and a GREAT evening of slot racing.
Flexi NASCAR and Flexi GT Scale. Both with sealed 16D Parma motors.
Still remain surprised at the fact that there can be motors THAT BLOODY FASTER THAN MINE!
But I'm not sore.  Nooooooooooooo not sore at all.

The drive south to Albany was fantastic following the Willamette River on the two lane, despite the 90 degree heat and coming in last yet again.... I still had a great time!
Tomorrow Bob is going to get a surprise when we race Go-Karts tho.  I am coming out for bear!!!!

 

As for the difference between the Lotus bodies.  I had not noticed that at first, good eyes Rick.  This might be a deal breaker... but, let's not tell Victor till he sends me the body.  

'cause I could still use that one on a later project.  If the gear doesn't clear.... then the long nose body will suffice since that was the plan in the beginning.  Or make it work as Bob suggests.  Just need to get the chassis done first... right?
Of course right!