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My sexy new JK C43 GTP car - step by step


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#1 Pablo

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Posted 02 December 2016 - 02:09 PM

Chassis prep 101: I didn't really find any serious burrs on the edges so I just gently:

- ran a small fine file to all edges top and bottom, followed by 400 grit

- spun a round file in all the holes - bite bars, bushing uprights, and body mounts

- wet sanded flat parts of both tops and bottoms with 400 grit wet/dry

 

IMG_3820.JPG

 

Not sure if I'm going to use the stock bite bars yet, so I left them alone for now.

 

I sanded the motor brace also, just to ensure it's fairly flat and has fresh new metal for solder.

Yes, it's overkill, but I have lots of time...   :)


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#2 Bill from NH

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Posted 02 December 2016 - 02:28 PM

We wondered where you were hiding the past couple of days! :)


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#3 Pablo

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Posted 02 December 2016 - 03:15 PM

Not hiding, just prepping cars for The Dungeon in 2017 :)

 

First thing I did on the center section was check the tilt.

I need "some" - the rules I'm building for are no fronts, no min. front clearance, and .032" min. clearance rear.

Mine, out of the bag, was angled very slightly down. Tongue Tweaker fixed it easily - I held the wings tight on the block and they stayed flat.

Then I checked it on my flattest block - it was plenty flat enough, nothing to correct.

 

IMG_3826.JPG

 

Pan section needed some minor hand tweaking to get flat, no problemo.

 

IMG_3830.JPG

 

I found doing one half first with the other half off the block, then the other half, then all together, makes it simpler.

When I get to the point of questioning which is flatter - the chassis or the block - I know I'm done.  :dance3:


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#4 Pablo

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Posted 02 December 2016 - 04:53 PM

Before I examine the stock bite bars, I was curious about something -

now that I have a flat two-part chassis, will straight pieces of (.039" front/.047" rear) wires pass through the holes freely?

 

IMG_3833.JPG

 

Yup. They went right through absolutely perfect.

While my test wires were in there, I noted the design of the pan movement limiters.

Fore and aft limits are perfectly equal, and left to right amounts are slightly more rear than front.

Very precise, obviously designed that way and the further I go, the more I like what I see.  :good:


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#5 JK Products

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Posted 02 December 2016 - 04:56 PM

  :popcorm1:


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#6 Cheater

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Posted 02 December 2016 - 05:04 PM

You are learning.  :)


He had a good teacher... LOL!
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Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#7 MSwiss

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Posted 02 December 2016 - 05:17 PM

Greg,

How many posts does Pablo have to make in this thread, for you to upgrade him to tome status?

Mike Swiss
 
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#8 JK Products

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Posted 02 December 2016 - 05:58 PM

See, I want him to stop for fear of giving away too many of our secrets!


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#9 Cheater

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Posted 02 December 2016 - 06:09 PM

How many posts does Pablo have to make in this thread, for you to upgrade him to tome status?


He's already got his own subforum.

When he's done this thread will almost certainly be moved to Tech How-Tos & Tutorials.


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Gregory Wells

Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#10 Pablo

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Posted 02 December 2016 - 06:21 PM

Jaroslav Recek obviously understands what makes a slot car handle.  :good:
 
Bill of NH suggested the forward bite bar could be assigned double-duty as a front axle - I checked it - he is right. Would take some clever technique, but it's totally doable. :D Just for those who are challenged with front wheel mandates...
 
Another tuning design feature I noted is the pan crossover (which makes the chassis a two-piece vs a three-piece) does not interact with the center section. In other words, you have the advantage of the pans being connected, without the disadvantage of friction with the center section when the body moves.
 
In a situation where you actually wanted that friction, you can add some Lexan strips under the crossover and get it.


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#11 Pablo

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Posted 03 December 2016 - 05:46 PM

Bite bars - here is what I found. The bends and curves that form the attachment end(s) make it practically impossible to lay it on a block and expect it to be flat. I tried to make them so, and couldn't. By no means is this a problem, and I'm sure you can just use them as is and do fine.
 
I set about to see if I could improve on them. My first thought was, small pieces of square tubing soldered to the pans rear, and .050" keepers outside of simple straight pieces of wire, front. The rear would be a piece of cake since it's basically the same way the Cheetah chassis bite bars are managed. The front would require some work - .050" keepers would be too sloppy over .039" wire, so I'd have to drill out some .063" brass tube to .039" and shim them up to make the keepers fit nice.
 
IMG_3873.JPG
 
Wait a minute, hold the phone - about that time, I started to really understand the way the stock bite bar keeper bends work. They just need to be tweaked properly. All the small parts and tools got put away – all I need is a pair of pliers. My stock bite bars are done.   :dance3:
 
IMG_3867.JPG
 
Here is my method. The convoluted bends look complicated, but I finally realized they are very simple, and only perform one single basic function - keep the bite bar from falling out. They are well designed to do that, and I doubt it can be improved from that standpoint. The problem is, not only are they doing the basic job, they can also prevent the bite bar from being an "independent thinker." In other words, they are influencing the bite bar due to (unwanted) interaction with the chassis surfaces. So, I think all we need to do is ensure the bar is straight where it passes through the chassis holes, and prevent the curved/bent section from touching the chassis.
 
First, let the bent areas lay off the block while you ensure the main part is straight. Notice the light coming under mine – not good – easy to fix
 
IMG_3839.JPG
 
Now tweak the bent portion upward the way you want it oriented on your chassis. Just enough to ensure all of it ends up elevated off the chassis about 10 thou. Like this:
 
IMG_3862.JPG
 
Now the bite bars are laying exactly as they would without the keeper bends, and everything is still flat. Plus you still have the capability of rapid removal as designed.  :good:


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#12 Pablo

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Posted 03 December 2016 - 06:21 PM

Both tongue surfaces faced as usual with a Magnehone.

 

I'm not going to reinforce the tongue – JK says it's a stronger chassis, and my meaty fingers verify that. Whether due to the thickness, or different material, I don't know.

 

IMG_3879.JPG

 

Bunky, the gap between the pan finger and wing tip you called a flaw and fixed with a shim?  Well, I call it something else.   :dirol:


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#13 Pablo

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Posted 03 December 2016 - 08:05 PM

I checked the upright holes for accuracy and to see what size wheels will give me .032" clearance.

 

Looks like the JK C43 was designed for about .063" clearance using about .720" wheels. It's accurate enough so no drilling/filing/etc. is needed, and I'll probably race it with about .685" wheels.

 

Found a pair of VBX un-shielded ball bearings – after a lighter fluid bath they will be soldered in... tomorrow...  :)

 

IMG_3881.JPG


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#14 glueside

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Posted 04 December 2016 - 08:09 AM

Pablo gets it!!!
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#15 Koford fan

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Posted 04 December 2016 - 10:34 AM

I notice you have taped in middle on your bite bars. Any reason for it? Just test? How it looking without?

Great work so far.
Tom Blantern

#16 Pablo

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Posted 04 December 2016 - 10:38 AM

The bearing holes are precise enough, I didn't feel the need to jig it up before soldering home the BBs. Simply taped it down with axle center elevated .2975". This will make it (mathematically) clear .032" with .659" wheels or .062" with .720".
 
IMG_3885.JPG
 
IMG_3890.JPG
 
Slick 7 brace fits perfectly.
 
IMG_3889.JPG
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#17 Pablo

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Posted 04 December 2016 - 10:42 AM

I notice you have taped in middle on your bite bars. Any reason for it?

 
Good question, Tom, thanks. I simply wanted the bent end of the bar to sit high for the photo just to make my point clear about keeping it up off the chassis.
 
Without the tape, it doesn't sit so high. Doesn't have to – just enough so it isn't hindering the bar from doing whatever it wants.
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#18 JK Products

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Posted 04 December 2016 - 11:51 AM

The force is strong with this one.   :popcorm1:


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#19 Pablo

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Posted 04 December 2016 - 04:07 PM

Centerline permanently marked at the rear.
 
IMG_3906.JPG
 
I've been using a different technique than the usual sales receipt to set gear mesh on JK chassis lately. I like to end up with a 10 thou spacer inboard of the spur, so I tack the motor in with a 20 thou to the hilt.
Then the 20 thou is removed and 10 thou goes in. So far it's worked perfect every time.
 
Gears on my car will be 72 pitch 15/40. Hawk 7 motor has been broken-in and wire connectors tinned. You can see my tack solder blob on the lower forward edge

IMG_3912.JPG
 
I took the time to find the left/right balance point of the motor (at the angle it ends up in of course).

Previous chassis versions didn't always have the motor sitting in the perfect spot, so I'd compensate for it.
The C43 does. Laying flush with the gear side right in its nest, it's in perfect balance left/right. :good:

Also, the space between the endbell side and chassis on the C11 was really tight - the C43 fixes that.
 
IMG_3904.JPG
 
Motor is in its happy place, now it's time to install some bracing...
Paul Wolcott

#20 Pablo

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Posted 04 December 2016 - 05:38 PM

I was planning to install a S7-389 motor brace up front but the bite bar won't allow it. The standard JK brace and gear side attachment point will be plenty strong enough.
 
IMG_3916.JPG
 
I'm done acid soldering so center section/motor, etc., got a warm soapy bath scrubbing.
 
IMG_3921.JPG
 
Soon you will see why I titled my thread with the word "sexy"... :)


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#21 Koford fan

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Posted 04 December 2016 - 05:50 PM

Nice work, Pablo. I like it.
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#22 Pablo

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Posted 04 December 2016 - 10:09 PM

Thanks, Tom. 
 
The rest of the assembly was easy, no problems, nothing special other than the usual "Wolcott Ranch" race car attention to detail:
 
- pan doesn't need nursing to attach it - drop it over the center section, insert bite bars with a click, done. Brilliant design.
 
- Parma flag blueprinted, all rotating surfaces faced, Koford aluminum drilled nut and two 10 thou bronze spacers for tuning (one top one below to start), Slick 7 wires, TQ clips, Prime braid, Koford axle.
 
- spur gear balance tested using the BBs on the car – screw was the heavy point – tried a few different screws until I found the one that made it happy. :)
 
IMG_3932.JPG
 
The wheels I'll be using are .680" OD Alpha Wonder rubber on carbon fiber hubs and are .800" wide. I used a single thin spacer between spur and BB, a couple thin spacers between spur and (left) wheel, and two 20 thou spacers on the right side. Look close and you can see my marks aligned.
 
IMG_3927.JPG
 
My opinion is, the C43 has raised the bar in many ways and it's probably the easiest flexi chassis to make race ready of any I've ever built.

I give it three thumbs up (that's the max Cheater Wells allows).  :good: :good: :good:
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#23 Pablo

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Posted 04 December 2016 - 11:47 PM

My "sexy" chassis is dressed with a skin from ralphthorneracing.com

 

IMG_3940.JPG

 

IMG_3949.JPG


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#24 Ralph Thorne

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Posted 05 December 2016 - 12:08 PM

What happens to those chassis skins when you solder motors in & out of a chassis? Years ago we made chassis skins using 3M colored plastic tape, but we never skinned the motorbox.

 
Shouldn't be an issue. They are made from a material designed to hold up to high temps. Personally I haven't had any problems yet.
 
The chassis skin and car look great as usual, Pablo.
 
Thanks for spending the time adding nice pictures and informative text.
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#25 John C Martin

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Posted 05 December 2016 - 02:28 PM

I can tell you the skins hold up on a chassis dragging on the chassis ears as well... very impressive product.


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#26 Pablo

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Posted 05 December 2016 - 06:43 PM

Painted body clips - Testors "Star Spangled Banner Blue" lacquer.
 
IMG_3966.JPG
 
Body is a 7 thou O/S Bentlee. Paint job is just a quickie with same paint as the clips. Numbers are German font waterslides from Pattos.
 
IMG_3985.JPG


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#27 JK Products

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Posted 06 December 2016 - 07:51 AM

Do they have separate categories for roller concours and body concours? You might need that, Pablo. 


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#28 Pablo

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Posted 06 December 2016 - 09:46 AM

That's way too much paint to qualify as a parking lot job.

 

:)  Concur, but I will say:

1. it's lacquer and all joking aside I want it to last at least three races.

2. the photo makes it look a lot denser than it actually is - in fact it is on the verge of not passing tech if there was a 'must be opaque" rule.

 

There is no official concours judging at The Dungeon, Tim, but photos are always taken of all the cars in all three classes.

Bud Greene, John Clow, and Bobby Page always show up with concours quality cars.

I have to say, during lane changes Bobby's cars on his pit caddy actually look like a real NASCAR pit.

 

For you "horsepower" freaks out there, just keep in mind I'm a "buy a motor, put it in the car" guy. No cherrypicking going on.

 

I do enjoy walking around during lunch within eavesdrop range of Red Valantine, muttering under my breath the words:

"Dyno... last night on the dyno... Bud's dyno... 110K RPM... real amp sucker... Norwegian squid bearing lube."  :crazy:


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#29 Fast Freddie

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Posted 06 December 2016 - 11:44 AM

Pablo,

Are those body clips bent to be race ready?  Do you have a specific procedure you go through to make them "Pablo style" race ready.

I haven't always understood your method on how to bend the clips. Do you install the long leg in the front and then tape over the rear leg? 

I have a new C43 that I'm going to use the clips instead of pin tubing. I'm a proponent of pin tubes on just about everything and have used them since the early '90s but I thought for this chassis and one other one I have I'll give the clips a try.
Fred Younkin

#30 Tim Neja

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Posted 06 December 2016 - 11:45 AM

Always good to see how much prep these little chassis can take in helping them perform better!! It's amazing how many things can be checked and realigned on such a simple stamped frame.  

Thanks for all the tips, Pablo, and for taking the time to post about them with pictures for us less adept folks!!

Merry Christmas to all you slot heads!! :)
She's real fine, my 409!!!

#31 Pablo

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Posted 06 December 2016 - 04:55 PM

Yes, Fred, those are modified clips. The best way to learn it is watch the fast flexi racers.

I did post my method a while back, page #1, post 14, and page #2, post 62, here:
 
New Kurtis proxy car built by Pablo
 
After I punch the holes first time, I mount the body on the clips and note if there are any needing to go higher/lower or right/left.

Then I place squares of bulletproofing on the insides over the holes. Punch the final holes with the desired corrections.
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#32 Pablo

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Posted 07 December 2016 - 02:31 PM

When you punch your body mount holes, it leaves a raised nub where it exits.
Slice it off with a sharp blade (I use a scalpel), otherwise your body won't move freely.
 
IMG_4002.JPG
 
Clips are secured with tape. This also reinforces the bottom of the body skirt, precluding fouling.
Normally for a race car I use filament tape but this time I wanted to show off my sexy blue clips.
Transparent tape works fine.
 
IMG_4011.JPG
 
Cheater Wells and Jay Guard taught me this stuff years ago and it still works. :)
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#33 Pablo

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Posted 07 December 2016 - 03:32 PM

I forgot about the rear wheels needing an additional 10 thou OD to clear. :)

Other than that, this car is ready to test and tune. Weight is 86.6 grams.
 
IMG_4032.JPG
 
IMG_4029.JPG
 
IMG_4030.JPG
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#34 Pablo

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Posted 07 December 2016 - 04:16 PM

As an addendum, I'd like to say the rear upright brace probably isn't needed, as this chassis material is quite strong.

But I had one sitting here just collecting dust so I used it. No doubt in my mind it was simply overkill.

I chose not to double the tongue - due to the same reason - strong steel, and I didn't consider it necessary.  :)


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#35 Cheater

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Posted 07 December 2016 - 04:31 PM

As an addendum, I'd like to say the rear upright brace probably isn't needed.


Maybe, maybe not.

I think most racers underestimate the forces involved in the motor bracker/rear axle assembly, especially with inlines but also with anglewinders. And even more so with fast cars on highly-banked tracks.

One way to check whether an upright brace is warranted is to take your thumb and forefinger and squeeze as hard as you can to try to force the uprights toward each other. If you feel any movement at all, install a brace.

Here's a snippet from the T-Flex Tome giving another method for checking whether an upright brace is worth installing.

"On banked tracks, running fast C-can motors, a rear upright brace is necessary to keep the rear axle from binding in the banks; the rear of the chassis will flex under the loads it sees. You can usually see this yourself on an unbraced chassis: space the motor from the axle with a piece of paper when soldering it in place, and then take a black magic marker and color the axle for about 1/4 inch at the point where the can is nearest the axle. After racing a while, you will usually see that the can has been touching the axle, as evidenced by a silver stripe rubbed into the black marking."


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Never forget that first place goes to the racer with the MOST laps, not the racer with the FASTEST lap


#36 Pablo

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Posted 07 December 2016 - 05:45 PM

I did give it the squeeze test, believe me. I immediately sensed it doesn't need a brace.

Did it anyway just to show off. :)
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#37 Half Fast

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Posted 08 December 2016 - 11:10 AM

This step-by-step set-up guide deserves a place beside Greg's Turbo-Flex magnum opus! :good:

 

Cheers.


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Bill Botjer

Faster then, wiser now

 

 


#38 Pablo

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Posted 15 January 2017 - 02:16 AM

Track test was delayed a week due to icy, windy weather across the southern continental USA on Jan. 7.

 

My sexy new C43 GTP car worked great (yesterday), just like I expected. Right out of the box it was perfectly race ready.

 

In the short amount of time I had to test, here are my findings/opinions:

 

1. My estimation of needing to add a 5 thou flag spacer to compensate for the Ralph Thorne chassis skin was spot on and I was happy with my scum patterns.

 

Instead of burn marks on the underside of the chassis where it normally shorts out and slows you down, I got a slick surface that is slightly scratched.

 

The skin, IMO, performed exactly as advertised. It's still intact and all I did after the race was wipe it with lighter fluid. I give this product an A+.

 

2. I have no scientific data to back it up, but the C43 worked super for me, first time out. I didn't adjust a single thing. It will dive into a corner and plant as well as, if not better than, any JK chassis I've even driven.

 

I did way overcook some entrances into the dead man and every time it would forgive, plant, and turn.

 

Usually my JK chassis perform this way, so I'm used to it. All I can say is, this one does it and maybe a better driver could push it even further.

 

Here is the braid wear and scum pattern after the race:

 

IMG_4645.JPG

 

And after I wiped it with lighter fluid:

 

IMG_4659.JPG

 

Skin still looks great and ready to rock n roll again.

 

The 7 thou Bentlee body was completely destroyed in a really bad crash but the car worked fine right to the end.  :)  :good:

 

Damage assessment to follow, tomorrow, but I don't think there will be much.


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Paul Wolcott

#39 Samiam

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Posted 15 January 2017 - 09:34 AM

I seem to have exceeded my " Like " quota so here's my :good: .


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#40 Pablo

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Posted 15 January 2017 - 02:32 PM

Post-race teardown: zero damage, other than a destroyed .007 Bentlee body and the clips need a new paint job :laugh2:

Believe me, it took some really hard hits. The C43 is still perfectly flat and true. I didn't even bother to remove the bite bars.

It's ready for the next race :D

 

IMG_4666.JPG

 

I oiled and braid juiced the car a half hour before the race. Other than an emergency body fix and changing lane stickers, that's all I did.

No frantic motor cooling, tweaking, juices, magic squid oil potions, nothing. Change lane sticker and slap it down.

 

Just for trivia's sake, this car (with chassis skin) weighs about 5 grams more than my C11 car. I don't think it even matters.

 

My conclusion is, the new JK C43 chassis is a winner and, as advertised, much stronger than previous JK chassis.

It retains the magic handling flex of previous versions. Easy to race prep and very low maintenance.

You won't see top level racers ripping the body off and tweaking the C43 back into shape between each heat like the C11's.

I give it an A+ :good: :good: :good:

 

Mission accomplished. I'll go back to my vintage trailer now

 

image5.JPG


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Paul Wolcott

#41 JK Products

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Posted 15 January 2017 - 03:20 PM

Hey Pablo, 

 

You musta used one o dem "screamer unicorn" motors cause you tore the hubs right off the back of a dat bad boy. 

 

Thanks for the kind words.

Tim 


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#42 Pablo

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Posted 15 January 2017 - 03:38 PM

Yep, drove the wheels right off it :laugh2:  Motor was a Hawk 7 with a new secret break in method - dry at 3 V for 15 mins.

No testing no tachometer reading no dyno no cherry picking - bought one and put it in the car. Just the facts  :dance3: 


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Paul Wolcott

#43 elinsley

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Posted 15 January 2017 - 06:53 PM

Awesome build, Pablo!!


Eric Linsley

#44 Ralph Thorne

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Posted 16 January 2017 - 12:35 PM

Also that RTR skin only serves to raise the chassis cg .005, it only looks cool.

 

Dave, the chassis skin does look cool as you stated! However they are actually only .002" thick, and that would be such a small change in CoG that it would be virtually unnoticeable. The big plus to them is that they prevent braid arcing which is very much appreciated by track owners.



#45 Pablo

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Posted 16 January 2017 - 01:50 PM

25 thou JK C11 with steel 25 thou pans, no skin. The clearance rules it runs on is: no limitation in front, min. .032" rear.

The turn marshal says "Hey Pablo, your car is sparking over here" as I'm turning the fastest times on the track and winning the race.

I just grinned, nodded, and kept the trigger pulled as hard as I could :laugh2:

 

IMG_4675.JPG

 

IMG_4673.JPG

 

IMG_4683.JPG

 

The thickness of the skins issue may have been my fault, if it was I apologize.

I theorized some more flag spacing may be needed in order to compensate for the addition of the skin, so I guessed and added a 5 thou.

The first thing I checked after a few practice laps was the scum patterns. I was happy with what I saw and it worked fine so I didn't change it.

 

Anyway, the skins don't conduct electricity so those days are over for me :victory:


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Paul Wolcott

#46 gotboostedvr6

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Posted 16 January 2017 - 01:57 PM

The next thing I purchase at the track will end up being one of those skins.
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#47 Greg VanPeenen

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Posted 16 January 2017 - 08:42 PM

Paul,
 
Great build and a great read.
 
I have one question.
 
I have a diamond tool for spot facing the guide tongue top and bottom and the guide making sure everything is flat. I just came up from the work shop where I was working on two of the new JK chassis. Found the same thing with the tongues on both as they also had a slight downward tilt fixed that and then went to spot-face the guide tongue and found the top needed a little clean up then checked the bottom side and both needed extensive work to get them flat on the bottom.
 
I was wondering if you did this and found the same thing and just overlooked telling us.
 
Love your builds.

Greg VanPeenen

#48 Pablo

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Posted 16 January 2017 - 11:42 PM

Thanks for the kudos, GVP, and thanks for asking the question.  :)

 

No, I didn't overlook posting about facing the tongue - look at my post #15 on page 1, a very sexy faced tongue if I do say so myself  :crazy:

 

Years ago Greg Wells started training me on flexi building and I've been fortunate to have learned from his vast knowledge along with many other greats.

 

PA Watson, Jay Guard, Bill Fernald, Danny Zona, JC Martin, Biscuit, Swiss... I could go on. But the times, they are a changin' and the chassis have changed.

 

What worked on a T-Flex may or may not apply to a C11 or a C43. But some things will never change, like the importance of a smooth flag rotation.

 

My late night conversations after a day's racing with Greg and Jay always ended in agreement that a perfectly-faced flag and tongue with minimal wobble was optimum.

 

Having the hole slightly larger than need be was not considered bad. In other words, allow the flag to move laterally but keep the wobble minimized.

 

Swiss school of flag wobble suggests a "looser" flag connection is not a problem and he proved it in actual track experiments. Sorry if I didn't word that right but it influenced my thinking.

 

So my mindset nowadays is to make the rotation as perfect as possible but don't overthink it, and error on the side of "loose." If it self-centers every time but needs the nut a little looser to make it happen, I'm fine with it.

 

GVP, I don't know what tools you are using for adjusting tilt and facing. Here is what I use:

 

- The reason I like using a Tongue Tweaker to adjust tilt instead of just a bolt and nuts is, the washers are large and strong enough to adjust the entire rotating surface of the tongue as opposed to just bending a piece of it. I hold the Tweaker in one hand and hold the chassis down tight on a flat block so I'm only bending the tongue.

 

It's tricky on a stamped steel chassis – bend just a portion of the tongue and you end up with a creased tongue. Let the chassis lift off the block when you tweak it and you end up with a bent chassis with perfect tilt.

 

- You call it "spot-facing" and I don't know what that is or what tool you are using. Here is what I use:

 

tool.jpg

 

That's probably a lot more info than you bargained for, but I hope some of it may help you.

 

I didn't have any problem adjusting my C43 tilt and facing was easy.


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#49 Pablo

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Posted 01 April 2017 - 09:57 PM

My sexy C43 won GTP today.  :dance3:


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Paul Wolcott

#50 Pablo

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Posted 09 April 2017 - 04:54 PM

Here is are my second post-race inspection results:

 

-rear clearance check - more than enough remains - matter of fact, too much. My notes say .690 give the required .032 but I had them at .697.

I put 'em on the Hudy and spun to check for concentricity. They looked fine, so I took 'em down to .692 and called it done.

 

-thin yellow lead wires did their job fine for 2 races, but I don't have enough confidence or love for them to attempt 3. So they will be changed.

 

IMG_5539.JPG

 

-7 thou Bentlee body was an enamel paint color experiment for one of my vintage butyrate builds. It served it's purpose but is done.

 

IMG_5541.JPG

 

-new Ralph Thorne 5 thou Warrior body, rattle can painted with Testors One Coat Lacquer

 

IMG_5548.JPG

 

-my read of the scum pattern is slightly more than I like up front, and almost none in the middle and rear. To compensate, I'll add a 5 thou spacer to the flag and I've already lowered the rear by trimming the wheels. No welding burns, and I enjoy thinking it keeps my motor happy. You can debate the theory one way or the other all you want, but the fact is the competition cooked a motor trying to beat me  :)

 

IMG_5552.JPG


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