267 replies to this topic

[Pablo]

I don't hear anyone saying why super hard rubber fronts are good for these type cars. So I'm going with my gut feeling. I have some new front hubs and firm donuts on order from JK.

 

Axle setup will be just like Marco's chassis - imitation is the sincerest form of flattery - I like everything about the way he did his, so mine will be copies. I'll call them "Marco Split Axles" 

 

 

 

[Bill from NH]

When they were available, Sonic's 4.5" fronts were some of the best. They weren't super hard rubber but i think they had two different firmness.

 

Some of the JK JRL fronts were made using less than super hard rubber. Then they had those plastic ones that rattled all over a track.

 

I've got some Fast 1's 4,5" fronts that came with over-sized firm foam for user sizingon a tire truer.

 

You shouldn't have any problem doing what you plan to do.

[Marco Carvalho]

Thank you Paul, but I need to give the credits to that design to Lineo Fernandes - he is a legendary slot car builder from Brazil.

But, I did improve two things on his original design: 1 - made it out of .055" wire to have some movement and a "suspension effect" plus, the use of some light camber to reduce drag on the fronts (and sometimes to fit and look better).

Great to follow your builds!

[Pablo]

Thanks Marco    I may even use some .047 

 

Question: positive or negative camber?

[Marco Carvalho]

Negative. Always!

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[Pablo]

Thank you. Makes sense on a twisty track 

[Pablo]

Can't tackle the front axle assembly until the front wheels arrive, so I turn my attention to the pan assembly. At Mike Katz' "School of heavy chassis for heavy bodies" I learned cars like this don't necessarily need lots of mechanical foof like intricate plumbing to work well. So my plan is heavy pans that fit the body sides like a glove, hung via simple hinges.

 

At some point this car is going to need to weigh at least 150 grams complete, and how I make the pans is going to be my last chance. It's a narrow car that needs to pack in a lot of heft in a narrow package. I'm thinking .032 pans …...

 

First step was mocking the chassis up with all four jig wheels and spur in their actual final resting places at the planned track widths - 2 3/4" front and rear. If I can squeeze 2 7/8" out of them during the assembly phase, super. Right now I just need to know how to cut and hang the pans. Note how I had to cut some meat off the top of the RGeo jig tongue - it was preventing the body from laying at ground zero 

 

 

 

Pretty simple except for the elephant in the room - the body skirts on this Lola are extremely curved at the bottom. I'll bet a modeler would call it sexy. I call it a roadblock. No worries - I have a plan 

 

[Don Weaver]

Curves are beautiful.... !!

[Pablo]

The motor was bottled and labeled as a JK Hawk Retro used once at an R4 event years ago. Can I get a definitive motor ID from someone who can keep up with the millions of motors JK makes? I'd hate to have it fail tech at BP. I can see the words "Made in China" on one side of the can, and nothing else, no RRRRRR. I have no reason to doubt my Sharpie labeling, but ………..

 

 

 

[Pablo]

Looks like I'm not the only one who can't keep track LOL  Hopefully Red Valentine will chime in, he is a toothbrush motor ID expert 

[MSwiss]

With a long shaft, it's most likely an early Retro Hawk.

It's not anything hotter.

[Pablo]

Thank you 

[Pablo]

.063 pans. I'm undecided on the hanger wire size, .032 or .055. If I go with the .032 I'll probably use dual twin setups a la Tony P.

Maybe even add a third single one amidships.......

 

 

[bluecars]

Early Hawk Retro.

[Pablo]

Thanks Red

[Pablo]

I fooled around with many different body mount combinations to deal with the curved sides. The best thing I found was .025 brass strips bent up in stages, to be soldered onto the pans and holes drilled for custom made body clips. Holes will be drilled in the body slightly bigger than the clips to allow a hair of wiggle.

 

For now, they are roughly formed and cut

 

[Bill from NH]

I've seen 1/4" strips like these used with body screws on some International chassis & others. I assume you're not going to mount your body with screws. These strips could be drilled & spaced out to fit pins, body clips, solid pin tubes, even floating pin tubes. Small squares of industrial strength Velcro would also work. 

[James Wendel]

Hardbody racers in my piece of Oregon usually put a ledge on the edge of the sidepan, either machined-in or a soldered-on L-bracket.  Then the body is simply taped to the sidepan, giving a secure yet flexible connection. 

 

The downside is the visibility of even clear tape and the fact that tape will remove waterslide decals.

[Pablo]

Progress:

 

[Pablo]

JK wheels arrived, rims are R3L6E, .530 OD X .235 wide; donuts are D2F, firm, .425 ID X about .870 OD

 

[Pablo]

I decided to go with .032 for hanging the pans, three sets of duals a la Tony P. - each wire will be independent.

 

Note to Bunky - in tight hinge spots like this one, don't forget to fabricate and install the wire before placing it. I made that mistake one too many times but not today 

 

[Pablo]

If you read Keith's rules very carefully like I did, you know I cannot mess with the body skirts, period. The width between them on this body at ground zero is exactly 2.425". So I am making my pans exactly the same. In the final stages I may sand a hair off the plastic to eliminate any rubbing.

 

Excuse the photos for lack of hands to stage the caliper but I hope you can see the temporary shimming of the pans out with .025" brass strips to make them perfectly placed at 2.425 

 

 

[Don Weaver]

Looking good!  Anxious to see how the body mounts up to the pans...

 

Don

[Rotorranch]

I thought you could straighten the rockers. Maybe I misread the rules?

 

Rotor

[Pablo]

What's a "rocker"?