106 replies to this topic

[dc-65x]

My latest project started out with this photo in an eBay listing for a Pile - O - Parts. Note the item in the top of the photo circled in red:

 

 

The Ram packaging caught my eye so I zoomed up on it:

 

 

"Fuzzy wuzzy was a bear......"  I mean that's one fuzzy picture. What's that black voltage designation in the lower left of the label? Could it be the Unicorn of Ram 850/857 armatures......the might 3 VOLT!!!

 

I gots to know and luckily know one else wanted all that stuff that badly. I won the auction, kept the arm, 2 chassis kits and sent the rest of the stuff to Rodney to hopefully help with his restorations.

 

Here's the armature:

 

 

The Holy Grail.....the light your braid on fire..........the mighty 3 volt beast.  

 

Here's a comparison of the 12V, 6V and 3V arms:

 

 

 

The 6V is no slouch but oh man, that 3V  

[SpeedyNH]

they must've had fun winding those, through that narrow slot between those 7-pole lams! 

[dc-65x]

That's something isn't it.

[dc-65x]

Here's the old Ram 857 the arm will be going into:

 

 

But first that new arm needs some attention.....

[Lone Wolf]

Those are quite rare. I think you bought one new in the box from me like 10 years ago.

 

I fear I'll never lose my love for these old Padlocks.

 

Just something about them that harkens back to a different time in America.

[dc-65x]

I think so too Joe. I chose "dc-65x" (of Pittman padlock motor fame) as my user name on eBay decades ago, then carried it over to Slotblog. I didn't even have one at the time but that motor from the 60's left such an impression on me.

 

My 3 volt arm has a nice straight shaft but when checking for balance on razor blades it had a couple of heavy poles. So out came the epoxy and Kevlar thread:

 

 

Need to be careful and not use to large a diameter drill or to drill to deep or you'll blow through the thin web of the laminations:

 

 

I used the Kevlar thread to form a ring around the wires to the comm. When coated with epoxy it ties the wires together like Pittman did with their 6001 "Competition" armature shown on the right:

 

 

Might be just wishful thinking but it was fun to do.      Here's the finished arm:

 

 

I piled on the epoxy until the arm wouldn't hold any more and applied a little heat from a heat gun. All that epoxy just soaked down into the windings and holding the laminations together. Otherwise they could separate during drilling.

 

I didn't build up a coating on the surface like the drag racers did. I'm only running on 12 volts.

 

Modifications to the motor setup are next.....

[Bill from NH]

My RAND balancer, bought in 1967, came in a plastic box & was first used to rebalance a French 16D arm for my first Cuc.

[Pablo]

This project scares me. In a fun way 

[dc-65x]

Pablo, the Beast cometh...........

[dc-65x]

I'm using the front and rear motor end plates as motor mounts for the chassis. They get their mounting surfaces machined flat, drilled and tapped for 2-56 machine screws and the bearing holes opened up to .2495" for ball bearings:

 

 

They were finished off with a polish job:

 

 

The handy little bearing install and removal tool from Dynamic and some red Loctite made quick work of the ball bearing installation:

 

 

The back surface was lapped flat too:

 

 

I'm just blueprinting this motor and not cutting it up to lighten it. I want it to be strong as it will be a structural member for my chassis design....

[don.siegel]

You've got better eyes than me Rick! I noticed those auctions too, and won one of them, but didn't see the 3V arm - just assumed it was one of the "normal" ones... But, there's something just as astonishing in there, and I hope you kept at least one of them: the Thunderbird chassis! Never heard of those, and the two I got in the lot are both front wheel drive models, one for cans and one for the K&B Challenger - pretty much unique in the annals of slot racing as far as I know. 

 

Now back to the beast in your belfrey, or rather your road car. As usual, very much looking forward to this build. 

 

Don 

[dc-65x]

Hi Don,

 

I kept the Thunderbird chassis kits too. Both front wheel drive. One for an SP500 style Mabuchi and one for a Kemtron......very cool kits.  

[boxerdog]

I'm really surprised that you spotted that arm, and even more surprised that it will be the basis for a road car! 

 

Can't wait to see what happens!

 

dc

[Lone Wolf]

"and the bearing holes opened up to .2495" for ball bearings"

 

This statement is what separates you from all the rest.

 

Most people would say "I drilled a quarter inch hole for the bearings"

[dc-65x]

Hi Joe, a half thousandth undersized reamer, a little Loctite and the Dynamic bearing press worked great for installing the ball bearings.  

 

dc, I've been busy trying some ideas that may help the Beast get around a corner (or not  ). Even if it doesn't its sure been a fun project. Here are about half of the simple sketches I've used for the motor and chassis parts so far     :

 

 

And before I get ahead of myself, I'll finish up the motor. I used new Ram brushes and their spring kit. I'm using the heaviest spring:

 

 

With the magnet removed..............

 

 

..........the magnet was dead upon reassembly:

 

 

The "Big Dog" zapper..........

 

 

...........perked the magnet up:

 

 

The blueprinted motor ready for a chassis:

 

 

 

 

On the Koford power supply the motor was broken in and it sounds great  

 

Chassis time............

[Lone Wolf]

That is a treasure. If fact, what is that little red cross?

 

Could could it be a connection to the Nights Templar and the money pit on Oak Island

 

Sorry, couldn't help myself.

[John Streisguth]

Interesting that Pittman motors was located in Sellersville, PA, which is less than an hour from where I live.  Just for S+G, I had to do a google search.  Looks like they are still in business, although their motors look a little different now...

 

https://www.haydonke...c-motors/dc022c

[Isaac S.]

Nice motor, looks really good. But dang, 3V with heaviest spring!  And getting that plunger on there had to be hard  . 

[dc-65x]

I remember an interesting statement in a magazine article by Mike Morrissey (Captain of Team Russkit). He said in the early days before they settled on their inline "jaildoor" style 16D powered cars, they tried everything. Large, medium and small motors, rear wheel, front wheel and four wheel drive, single motors, multiple motors, you name it. They didn't have the fifty years of slot car experience we have today. The only way they would know if something worked was to try it out.

 

So that's what I doing with this build. I'm putting away my 50 years of slot car 20/20 keyboard hindsight and just building something fun. 

 

Here goes.....

 

The first big Ram 3 volt I built was this King Cobra hardbody drag car. It's power impressed me finishing on the podium behind 2 unlimited rail dragsters.:

 

 

It's an inline with the motor acting as a stressed member:

 

 

On its first test run it would wheelie and the braid would arc so badly I thought the thing was going to catch on fire.     The solution for that finished chassis was to add a ton of dead weight out front as far as I could:

 

 

Now it's time to turn off the 20/20 slot car keyboard hindsight.      For this car I'm doing something different. Instead of adding weight to the front, I'm reversing the motor position and shifting the weight of the motor as far forward as the armature shaft will let me. Here's a comparison with the new build setup and the King Cobra:

 

 

I'm placing this build in the late 1966 time period so I can bring in another thing to hopefully hold that guide flag down......an  ISO style chassis like the Cox Cucaracha used. The motor weighs a ton and hopefully that ISO arrangement will hold the guide in the slot.

 

Remember, it doesn't matter what that 50 years of hindsight tells me. It only matters that it's fun for me to build and that I get to see what happens for real and just not keyboard speculation.

 

And here's the start of my chassis. A hunk of 1/16" wall, square brass tube.........

 

 

   

[Pablo]

            This is already blowing my mind

[Bill from NH]

That square brass tubing will make quite a motor mount. 

[dc-65x]

Indeed Bill. The beast is coming..........   

[Slot Car Rod]

Rick, we discussed the mid front engine/motor layout.  Like a 1 to 1 scale Cheetah.

[Lone Wolf]

Mind blowing as usual

 

I was looking at the chassis mock up and was thinking about offset.

 

Somehow though, I thought you were too.

 

Since the motor is "theoretically heavier" on one side, will you be mounting it to take advantage of any handling "bonus" on a road car ?

 

Not sure if the motor is heavier on one side actually, just looks that way.

 

Maybe you can investigate center of gravity wise.

[boxerdog]

I remember that Cobra...