101 replies to this topic

[Pablo]

Second "rough cut" on the rears:

 

[Pablo]

As of today, I'm going to "QA" my main rail rods/wires.

 

 

Out of a "three-pack", two needed about 1.5" of bad spots removed from the centers, and one was unusable for rails IMO.

 

[dc-65x]

Holy smokes, Pablo. Checking for straightness on the main rails with a dial indicator. You've got me beat there!   I thought I was being fancy rolling the rails on a flat to check for straightness.
 

Bent mail rails do suck...

 

Onward, Pablo... 

[SlotStox#53]

Just the old eyechrometer for me. 

Wheels and tires looking good, sir. 

[Pablo]

Thanks, guys. 

 

Getting off to a slow start; last week I was sick, now I'm struggling with planning phase details I should have worked out weeks ago.

I now realize the magazine article doesn't address three big issues: wheelbase, guide lead, and if the rails are tapered towards the front or not.

And I thought I had the perfect steel washers for the axle tubes, and didn't.

 

Nothing is ever easy at The Wolcott Ranch, so I'm used to it.  One good thing, I found the "secret drawer" at Lowe's stashed with K&S stuff. 

 

Thanks to some help from my good friends, I may actually solder something here soon.

[Pablo]

Found steel washers, perfect ID (slightly bigger than the axle) but OD was a little bigger than I wanted (.310"). So I turned 'em down a little, to about .265". I'll polish them after they are soldered to the tube pieces.

 

 

Genuine Russkit 495 bracket

- modified to accept inside rails

- axle tubing holes hogged out to 7/32" with a Uni-Bit

- motor bushing and mounting holes slightly enlarged and countersunk

- flattened, straightened, and sanded clean

My flag blueprinting mini-jig is a nice tool for this.

 

 

Motor bracket is ready.

 

[Bill from NH]

Wheelbase and guide lengths are usually dictated by the body used. I haven't had the body you plan to use, so I'd say measure it twice, cut once.

 

If I was building a generic 1/24 F1 chassis, i'd use a 4.25" wheelbase and a .75" guide lead. These dimensions would fit the majority of the 1/24 cigar-shaped F1 bodies.

 

Nope, this Team Russkit car doesn't use tapered rails. Construction photos and the Martin Windmill cars will back this up.

[Pablo]

Wheelbase and guide lead lengths are usually dictated by the body used.

 
Ouch. My ears are burning so bad I had to run get some ice. 
 
Thanks, Bill, for the confirmation of "no taper" on the rails. 

[Hworth08]

The open wheel cars back then, as today, were a handful to race but a ton of fun. A 4.5 inch wheelbase and as long a guide as the body allowed made them easier to race.

 

Car Model rules may have been strict enough to keep the wheelbase close to the original. Otherwise Bill is close to correct.

[Pablo]

The orange wheels are slightly wider than the blacks, so I planned tube lengths for them at 3.00".

 

Twin Slick 7 20 thou steel spacers on each side to allow a needle oiler to lube the washer faces.

 

The black wheels will use an .063" against the hubs and a single Slick 7 against the washers for 3.00".

 

By adding an extra .063" spacer on both sides to either setup, the width will be about 3-1/8" or 79.4 mm.

 

Just to triple-check my math, I mocked it all up.

 

 

[Asp]

The wheelbase of the real Honda was 2390 mm, which will give a scale wheelbase of around 4.00"... too short maybe for good handling.

[Pablo]

Noose measured the body today; wheelbase will be 4.00" and guide lead 5/8".

[Asp]

Close to scale wheelbase then... very good.

[Don Weaver]

Whoo! That be short. 

 

Don

[Cheater]

Pablo,

 

Since the rear tire diameter of the car is known, use the cover photo to calculate the wheelbase of the car shown there, just as a double-check. Or use a pic from the article.

[Pablo]

Wheels complete at .880" OD and 1/2" tread on track.

 

One SBR tire has a small bubble on the sidewall, an imperfection in the donut.

No big deal, so I left it alone.

 

[Pablo]

Washer ends pre-polished with 2000 sandpaper
 

 
.300" tube pieces go through the bracket sides and up against the bushing flanges.
When I torched the bracket/bushing/tube joints (both at the same time) the acid and solder wicked out into the washer/tubing ends.
Good thing I had them secured and in perfect position at the time (Thanks, dc-65x.  )
I added a little more solder to them for aesthetics.
 

 
Care must be taken to ensure the washers don't end up touching the axle and rob horsepower
 

 
I'd like to thank a lot of people for helping me get this car started, dc-65x, Tony P, Bill from NH, John Havlicek, and especially Noose.

If I forgot anybody, get in line behind Noose for an opportunity to throttle me - I've been driving him crazy with questions and favors for two days now.

[Cheater]

I know just how Noose feels, since you used to do the same thing to me... LOL!

[Bill from NH]

You're closer to him than the rest of us are. You might not be off the hook yet.

[Cheater]

BTW, Pablo, is that all you got done today? LOL...

[Pablo]

Correct, sir. 

[endbelldrive]

Lookin' good, Paul. Setting up the inline bracket and bushings used to take me a long time for some reason. I think it might of been one of those goofy zen warm-up things or it could be I was making it up as I went along and didn't have the design figured out. Probably the latter. 

[Pablo]

Thanks, Bob. "Goofy Zen warm-up" made my ears tickle.

All "jiggyed up", but I decided to wait for the body before soldering the rails.
 
Meantime, lots of prep work to do.
- inside of front axle tube polished with 2,000 grit wet/dry
- first rail bent at 90-1/2 degrees (vice 90) to allow for downward tilt of bracket
- bracket bracing wires pre-tinned to prevent oxidation
 

 
I discovered a neat new trick. When spinning tubing in a drill to finish the ends, direction of rotation doesn't matter.
 

 
By using it in reverse, the chuck doesn't continually lose its grip.
The downside is, at some point I will forget it's in reverse and try to drill something. 
Won't be the first time...
 
Hey, Cheater, you want me to build up that sweet jig motor for you when I get done with it?
It only got hot a couple times. I could have it done by later tonight...?

[Pablo]

All chassis parts prep complete.
 

 
Weight was polished by set-screwing it to a piece of tube, spinning it with the drill, and hitting it with 2000 grit.

Then I polished the bore with a spinning 1/8" axle wrapped with the 2K grit.


 
Funky said, "That's overkill", but I had fun doing it.

[Cheater]

If you are having fun, that's all that matters.

As Rick always says, "Onward!"