85 replies to this topic

[dc-65x]

In 1967 the GE Silver Hornet motor was the great USA hope to displace the Mabuchi motor from the Pro racing events. This motor never caught on with the Pros and Dynamic’s hopes for the motor were indeed, “just a Mirage”. But Dynamic’s Mirage Handling Body is a winner and works really well with the GE motor.

 

Here is a little background on the real Mirage car from its designer Pete Brock, a link to his website and a picture of the car in its original form:

 

Design at Shelby American

 

The first USSRC racer designed by Peter Brock in 1963 was the super lightweight Nethercutt Mirage. Commissioned by SoCal racer Jack Nethercutt, just before the trend toward downforce aerodynamics pushed the sport into the Can Am era, the low frontal area Mirage was the last of the light weight/low drag road racers. Powered by a small aluminum Olds V8 the Mirage had one of racing’s first monocoque chassis that even featured ultra light, riveted, sheet-metal wheels! Since it was being built by a small but dedicated group of volunteers the project moved very slowly. When it was finally debuted, two years late in 1965, the Mirage was already obsolete.

 

 

This is a very slick looking car which is typical for Pete Brock’s designs.

 

 

 

I’m going to try and give this motor a shot to see how fast I can make one run and especially how well I can make it handle. This has been done before with various “Dyna-Scratch” style brass rod and pan style chassis utilizing the Dynamic motor mounts and even monster Havlicek rewound motors.

 

With this build I’m going to forego the usual Dynamic frame entirely and do what I enjoy doing most, scratch building a brass rod chassis. It’s going to be in the style of the cars in the 1967 Car Model Magazine LA Championship Series races.

 

But first, I need to get the motor in order. Here’s the starting point for my project. It’s a Dynamic Mirage RTR with the GE motor:

 

 

It’s an eBay find that actually ran really strong on my track and has good power:

 

 

 

The motor was really filthy and it looked like it might have been messed with……I mean owner modified. It had 2 different size screws holding the end bell in place. I wouldn’t be surprised if it has been pull apart and maybe one of the hotter arms Dynamic offered installed:

 

 

Here it is pulled apart:

 

 

Man, what a mess!      What really surprised me was the wires wrapped around the commutator tabs have NO solder left on them! It’s like it got so hot the solder just vaporized. But the car ran and ran strongly even with the wires just loosely wrapped around the comm tabs.  

 

I’m glad they didn’t let go and lunch the motor

 

 

I re-soldered the wires with Slick7 highest temperature silver solder and the arm now reads .3 ohm on each pole:

 

 

This arm doesn’t seem to have very many turns of wire wrapped on it. 

 

Next I’m going to disassemble a new old stock GE motor and see how it compares with this one. 

[Tim Wilkins]

Nice project Rick.  Looking forward to it.  That was my first slot car, the GE motor with the Mirage body. The store owner at Tiny Tim Hobbies in Northridge California suggested the car to me and as a 12 year kid, it seemed FAST! If you can get your hands on the rewound armature version, it was quite quick for its day.  The floppy pans came a bit later and helped the handling, but was never great compared to the sleeker 16D motors.  What kid wouldn't be influenced by this advertisement

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[slotcarone]

Looking at that arm makes you really appreciate the artwork of John Havlicek!!

[NSwanberg]

Looking at that arm makes you really appreciate the artwork of John Havlicek!!

That is one nasty kink in the wire at the top of one of the poles. Me suspects a hand wind.

 

In their business plan I wonder how many of these little motors GE expected to sell?

[don.siegel]

Judging from ebay, they wound up selling a fair amount of them! 

 

Another great project Rick, looking forward to seeing what you do. 

 

Two bits of information on this motor. 

 

First, almost right from the beginning Dynamic realized it wasn't going to be competitive with the lighter, flatter models then in vogue; in fact, they very quickly added to their ads that it was a "great rewind candidate" or something like that. Even the first big article on this motor, in Car Model or Model Car Science, while trying to be really friendly to an advertiser, couldn't hide that it wasn't really competitive as sold. 

 

Secondly, we've seen a lot of these at the Bordo vintage races and they're very competitive in this context. In particular, we shoot for more scale tires, so the motor isn't penalized by trying to run with 7/8" or even smaller tires - for which it really wasn't designed. One of the Italians won or finished high up in races using a regular sidewinder chassis, without the idler gear. And the extra weight actually helps when running on silicone (now banned) or urethane tires - no spongies, no moo, that changes a lot! 

 

The GE is a torque monster, as it says in the instructions and you can go with a very high gear ratio (low numerical). I did one a couple years ago that ran very well, but was braking sideways until I lowered the gear ratio and added a chunk of lead under the Dynamic frame - that quickly sorted out the handling! (altho a real floppy pan would have helped - ground clearance is still way too high on the Dynamic inline frame with more or less scale tires (at least 1 inch). 

 

If I remember right, the stock wind already used something like No. 28 wire - they also did a rewind version with #26, but don't remember seeing aftermarket hop-up arms - anybody have one of those? 

 

Don 

[JohnnySlotcar]

I have one of the "hot" arms. Sent it to Alpha for varnishing and balancing. Winter project fer sure.I won a 2 hour stock car enduro with one I got as a race prize in an earlier event. Motor came with a rear bracket, so I built my chassis with it. Still have the car! Enduro race prize was a MPC 57 corvette kit.

[dc-65x]

Thanks for all the interest and comments.
 
Here some links Gary Stelter provided in an earlier thread on these GE motors:
 

Here:
http://www.vsrnonlin...08/GEMotor.html
http://www.vsrnonlin.../CMV6N2_p42.jpg
http://www.vsrnonlin.../CMV6N2_p41.jpg
http://www.vsrnonlin.../CMV6N2_p40.jpg
and finally.....http://www.vsrnonlin...08.html#Letters

[John M Wimett]

This looks like a great project, hope to see pics when finished.

I might be the only vintage slot car nut in SE Washington!

I have followed your builds on Ebay last couple years and they are truly works of art.

 

I have restored, put back together, saved about 27 vintage slot cars from Ebay, but nothing compared to the level of detail that you achieve.

 

One question, have you ever done a tribute Russell or Quintana Chaparral slot car, if you have I missed them.

Your research, photos, history and level of build are an inspiration, keep up the great work!

[Lone Wolf]

Pic is not great but here is a 40/27 that John H. did for me. Smooth as silk and really whistles. Notice the nylon is gone and there is room for about 300 more feet of wire 

 

It's slated for a drag project as I've never seen one used in that fashion

 

 

As always, looking forward to more on your build. 

 

P.S. Rick, been seeing you masterpieces on Ebay.

 

My question is how in the world can you bring yourself to part with these things? 

 

Not sure I could do it if I were you. 

 

 

[dc-65x]

One question, have you ever done a tribute Russell or Quintana Chaparral slot car, if you have I missed them.
Your research, photos, history and level of build are an inspiration, keep up the great work!

 
Thanks for your support John. If you mean Jim Russell, I built this car of his:

Russkit’s "Mighty New Motor"

 

I don't know if I'm familiar with Ron Quintana's Chaparral but I've always wanted to build his Russkit teammates version:
 

 

P.S. Rick, been seeing you masterpieces on Ebay.
 
My question is how in the world can you bring yourself to part with these things? 
 
Not sure I could do it if I were you.

 

Hi Joe,

 

When I was laying in the hospital recently, I kept thinking of what in the heck my wife was going to do with all my cars if things didn't go OK for me. Funny the things I thought about. Anyway, when I got home I decided to "thin out the herd".

[Lone Wolf]

Rick, one good thing that came out of all of this is that people all over the world will be able to have the great pleasure of owning, displaying and maybe even racing one of your one of a kind masterpieces.

 

Glad your home and I suspect feeling better. 

[TSR]

An interesting tidbit about the GE motor: it was also offered to Cox, of which R&D department fitted in a pre-production Ford Galaxie. For an unknown, but likely reason (no ABS braking! ) it was rejected. The factory prototype survived and is today in the LASCM museum collection.

[88honcho]

Gator Dad told me he was always of the belief that the Nethercutt Mirage was the basis for the Cox Cuc.

 

http://slotblog.net/...ie/#entry465174

 

So... he built one and sold it off many years later.

 

http://www.worthpoin...ercutt-20831833

[dc-65x]

I decided to opened up a new old stock Dynamic GE motor #208:

 

 

 

The armature has a ton of wire on it......perhaps slightly smaller gauge wire too. Here it is on the right compared to my used "mystery" arm:

 

 

The "new" arm measures .5 ohms to the "used" arms .3 ohms:

 

 

Hmmmmmmmm........................

 

 

[Horsepower]

Rick- I hope you are feeling better and welcome to the wonderful world of hospitals.  Thanks for throwing me some credit there. Those were definitely better days. Just as an aside, those 3ADM motors that were so anemic were bought by me in my sucker days. Strangely enough, someone saw that post and a guy who was actually looking for that particular motor contacted me and wanted to buy one at a fair price.I told him I would give him one if he would just tell me what he was going to do with it. It turned out it was a motor for an old arcade machine and he had been looking for years for one! Later he send me some pictures of the machine with a picture of the guts with the motor in place. Kind of a kick! OK, back to the thread at hand. It looks like a good one!     

[havlicek]

Hi Rick,

 

     Thanks to your neato detective work, it looks clearly like your arm was dewound, an easy way to soup things up...and maybe that explains the bizarre missing solder at the com tabs(?).  The GE motor was an interesting one.  The very wide crown, but undercut lams makes winding these arms a little more challenging.  Those nylon insulators take up gobs of real estate, and at least partly explain the ridiculously sloppy coils (*well...at least partly).  Removing those insulators opens up loads of space, makes for tighter coils with shorter wire runs for the same number of turns, and might even help an itty bit with less rotating mass.  The coms are the same as those sold for 36D motors and are strong as heck for the time, by far the strongest period coms I ever came across...but are really short, making hardware clearance a PITA ...at least in the Mabuchis.  Also, the com slots are *really* wide, so they can foul up with brush dust and gunk PDQ.  Doing a good com-cut certainly helps that.  The magnets are the thinnest of any period motor I've come across as well, but are surprisingly strong.

    I don't remember much about Joe Lupo's above, except that there's good potential in them.  I figure yours (at .3 ohm) will probably be a solid performer, and if it IS a dewind, whoever did it was on the right track for the GE.  Neat thread here, and beautifully documented!

 

-john

[Jairus]

I find it interesting that this thread was started on the same day this ebay item popped up.... 

http://www.ebay.com/...=STRK:MEBIDX:IT

 

Coincidence?

[dc-65x]

Must be an omen Jairus! I sold an inline version of that kit a few weeks ago on eBay. I didn't want to "bust it open" once I found the used car shown in this thread. My eBay handle is the same as here: dc-65x.

 

 

I was wondering if that used arm might be a de-wind John. I was expecting a larger variation in resistance readings. The wire color is slightly different but it might vary from one lot of wire to the next.

 

Unless a factory "hop up" arm surfaces, I think I'll go with the "de-wound" arm in the new motor setup.

[Tim Wilkins]

I find it interesting that this thread was started on the same day this ebay item popped up.... 

http://www.ebay.com/...=STRK:MEBIDX:IT

 

Coincidence?

The Ebay listing sidewinder chassis kit is missing the hard to find idler gear and other parts that would come in the complete sidewinder kit ( part no.454 )

[dc-65x]

I setup the dewound arm in my hobby lathe. A pinion gear on the free end of the arm is supported in the lathe's live center. I checked the alignment of the arm with a half thousands dial indicator. It was running true but you could see the comm wasn't round. It dipped down at every comm slot. I used a black Sharpie on the comm and took a cut:

 

 

Here's the finished arm. It's had its comm wires tied, slathered in epoxy, baked and razor blade drill balanced:

 

 

Now I need to reassemble it and see if it still runs!  

[Bill from NH]

Was the use of black Sharpie for indicating where you cut the comm or as a cutting lubricant? In the past, I've heard it used for both.

[Tim Wilkins]

Original pinions were .093 shaft size.  Are you confined to using NOS pinions?

[dc-65x]

Hi Bill, I used a Sharpie because I had it handy. I used it as a visual aid and a light oil as a cutting fluid.

 

I've got lots of 12T vintage pinions to try Tim. I hope to find one that mates happily with a Weldon crown gear.

[Pablo]

I have a baggie of old pinion horrors if you need any.

[dc-65x]

Thanks Pablo, I'll see what happens with the pinions I have........

 

I assembled the motor and proceeded to break it in. It sounds really healthy but it was running pretty hot. I guess that shouldn't be a surprise since it already melted the solder off the comm once before.

 

I decided to add 4 extra holes to get more air into the motor so it came apart again. My little milling machine and a carbide end mill made quick work of it:

 

 

Here's the finished motor:

 

 

 

Time to look through the 1967 race reports and get some ideas for a chassis design....