138 replies to this topic

[dc-65x]

This project is going to be a car based on the 3rd R&C 1966 race report for GP cars. This Lotus of Ken Larimer is one of my favorite slot cars of all time:



The race report and rules I'll be working from:











Since there is no picture of Ken's chassis I'll just make up a two rail per side similar to Dave Grant's Brabham chassis....



........but with a 3-rail drop arm and all brass rod construction like Don Peters Ferrari.

Just for fun I decided to make up my own close fitting axle tubes. I used brass bar stock in my lathe and turned the OD to 5/32" and reamed the ID to 1/8":



Here my custom "tubes" are soldered into a Russkit bracket. An aluminum spacer keeps them from moving as I solder rails on:



What's that nice white background . It's my new Rick's chassis jig :



I slipped 3/32" aluminum tubes over the 1/16" pins. Using the jig's 7/8" hole spacing this gives the exact width of the Russkit bracket......neato :



Time to lay the rails in place...............

[TSR]

So if I understand correctly, Fred "Kenny" Larimer won the No-Belt prize?

[Duffy]

Just for fun I decided to make up my own close fitting axle tubes. I used brass bar stock in my lathe and turned the OD to 5/32" and reamed the ID to 1/8"

Wait, that's legal?? Excessive accidental "Tinning" of brass tube has snuck in, but this? What's to keep me from turning up phosphor bronze "tubing" and forestalling replacement of axle carriers for, ohh, maybe four races? I jus' dunno about this.

So if I understand correctly, Fred "Kenny" Larimer won the No-Belt prize?

Oh ouch, ohh very very ouch. And the driver strapped in the tightest wins the "Pull-it's HERE!" prize, y'think? Whenever a Frenchman starts messing about in the "HAR"-ness department, we need a little Yank to cinch things up.

Mal a'Prop

[TSR]

OK Duff, You win a Pulitzer for the ""Pull-it's HERE!".
I'll give myself the belt.

[dc-65x]

I don't know but I guess I'm off the hook for having to paint a shoulder harness on my driver . I sure like the way Kenny's Lotus and Doug Henline's Brabham look .

[TSR]

Rick, You MUST put the belts on... looks way more cool.

[dc-65x]

OK, if I can find a paint brush that doesn't shake all over the place. I don't know what's wrong those darn things .

[endbelldrive]

OK, if I can find a paint brush that doesn't shake all over the place. I don't know what's wrong those darn things .

You have to lubricate the brain and the arm with a couple of beers... ...or you could use a Sign Painter's helper aka Mahl Stick. I've been using one since puberty and the darn things are almost second nature.
Link: Art Glossary: Mahl Stick

[Duffy]

...or you could use a Sign Painter's helper aka Mahl Stick.

...Ah. Also sometimes called (see post #3) the Mahl a'Prop.

Look, I can't help it. I'm just sittin' around waiting for the solder to dry.
Bad Duffy

[havlicek]

Build on...build on Rick! (he says as he gets out his notepad and pencil...scribble scribble)

-john

[GTPJoe]

Hi John!

Sir, I used to be a scribbler too when watching (and learning) Ricks great builds.
Now I "Cut and Paste" into MS Word and can print out the pics in color and have it saved not only online but burned on a CD forever!!!

Hi Rick!

WOW, love that new Ricks jig. Here's hoping you build lots of cool chassis on it, like this one!!

See ya!

[dc-65x]

Thanks guys .

I've got the main rails bent up and I'm doing something a little different with them in the back. Anyway, while I'm a solder'n here is the armature I'm going to try (and I stress, "try") in this car's motor. I didn't take a "before" picture but here are the other arms it came with. They are all in pretty sad condition :



What a mess . Another brilliant Epay purchase . I was intrigued by one as it looked very 1966. It checked out at .4 ohms. The (I think) Tradeship comm has a little CCW advance but had about .008" of "valley of the comm". I cut the comm and cleaned the arm up:



Amazingly, the thing seems fairy well balanced but I gave it a static balance job on my Tradeship balancer. Here is the arm ready to rumble:





Oh, John, what the heck are these little twists of wire on the back of each stack.....boo boos



Off to the world of acid fumes and burned fingers

[TSR]

Rick, looks like a "star" wind from the glob on one pole...???

[havlicek]

Howdy Joe!...time to sit back and watch the master One of the great things about Rick's builds (besides the actual builds themselves of course) is how well he documents them and gives the reader both the "nuts and bolts" as well as a sense of the history involved. It all gives the projects a sense of...context that is so important in my mind. Maybe folks who see these cars as "relics" compared to the latest-greatest nuclear-powered 10 gram zipper see this all as "quaint", but this is where it all came from! It's obvious we're dealing with a guy here that loves the sport! Back to our regularly-scheduled show!

-john

[Jairus]

Oh, John, what the heck are these little twists of wire on the back of each stack.....boo boos

Not John.... but I think those wires do not carry current. Those look like "straps" to hold down the winds to me.

[Tex]

Man, I LOVE the look of those arms that are totally encased in epoxy! Smooooooooth.

[dc-65x]

Man, I LOVE the look of those arms that are totally encased in epoxy! Smooooooooth.

Check the one out on the top left:



I'm going to do something with that one some day .

Rick, looks like a "star" wind from the glob on one pole...???

.... but I think those wires do not carry current. Those look like "straps" to hold down the winds to me.

"Star" wind, "straps"..........so much to learn. I would welcome tutelage on these matters . I did have a real problem getting the comm tabs and tab windings to clear the inside of the end bell as you will soon see...........

Thanks for the input .

[havlicek]

Hi Rick,

Sorry, I didn't notice your question earlier, but my answer is..."beats me" Hazarding a guess, I'd have to agree with Jairus and say they're an attempt to corral those unruly wires into some semblance of order If it were a "star wind" (which I've never done and my understanding is that they offer no advantages in most cases), I think there'd be only a single pigtail for all three poles.

-john

[dc-65x]

Star winds, pigtails, globs on one pole................BAM!

Check this thing out:





It's got globs on all three poles and three pigtails:



But it's a triple wind from the Squire E. Openshaw Jr. collection:



I looked carefully at my other armature again and I was mistaken. It only has the pigtails on 2 poles.....a double wind perhaps??????????????

[havlicek]

The mystery continues...as long as it runs, it could have oxtails AND pigtails :-)

-john

[dc-65x]

Okie Dokie, I'll put the motor on hold for now as I've done some solder'n . With the 4 main rails bent to shape, trued up and the ends left long everything just fell together in the jig:



There are pins to line everything up nice and square:



Pins align the front body mount/drop arm up stop:



More pins align the drop arm pivot tubes:



OOPS! what a mess "life's messy, clean it up" :



When this happens to you just suck the crap-O-la out of there :



All better now :



Out of the jig and ready to be trimmed up. The long ends on the main rails help me make sure they lined up vertically. It does look goofy though :



I find it easier to use one long piece of tube for the drop arm pivot and cut the center out. Sometimes there is stress built up and when the tube is cut it will grab and break the cut off wheel. You can first cut the tube in half and gently move the wheel side to side as you cut. This widens the kerf so the wheel won’t break:



All 12 pounds of excess brass is trimmed off and the K&S Metals Company should be very happy with my technique :



All the solder on top of the rails where the iron touched will be sanded off with 320 and then 600 grit sandpaper. This is completely unnecessary but I like the way it looks to have as much of the brass exposed as possible. I'll also chamfer the ends of all the rods and tubes where they were cut off. This usually takes me longer to do than the actual building.
But, when I'm done, you can run your hand over the chassis and not feel any shape edges. Just like my old German Journeyman Machinist teacher taught me........thanks Otto!

"Get to the burr bench apprentice!"

"OK Otto."

Onward.............

[dc-65x]

Here it's deburred and sanded:



Here it's been gone over with a wire wheel in a Dremel at LOW speed for a coarse polish:

[Duffy]

Okay, I see what John Havlicek meant about how you document a build! If ever there was a use for the popcorn-noshing Smiley, this is it. (I still won't use the silly things.)

To me, with any build, the thoughts along the way & the problems solved are where the life is. Telling that story the way you do here is a real gift to us. Thanks!

Duffy

[havlicek]

Super nice Rick. Are you using Sta Brite?

-john

[dc-65x]

Thanks Duffy. "Solving problems along the way" is an understatement for the bone head thing I've done on this chassis. The front and rear uprights for the outer rails were not supposed to point straight up. I wanted to angle them to the outside. There is something like that going on (I think) on the rear of Kenny's Lotus. Removing the outer rails will be an adventure if I decide to do it. Anyway, I'll post pictures of the finished chassis as it is now while I decide if I'm going to tear it apart.

Hi John, yup Stay Brite silver solder and Stay Clean acid flux.