New Fox Chassis

Post by **Mark Fox** » Wed Mar 04, 2009 2:30 pm

Hi All,

As a followup to Stoo posting a pic of my new chassis - I thought a few more pics and details may be useful.

A few details: -

Weight is 118 grams.
Guide length is 4 15/16".
Wheel base is 4 1/16".
Rails are 16#.
Brass plate is 16#.
Body movement is via rattler pin mounts.
Apart from pin mount rattlers there is only very minimal chassis movement - the pans are attached to the front "crash bars" via .032" wire.
Front wheels are independent.

Some of the photos do not have the brass spring as I tested it without at first and then added the brass to try and stop a bit of tramping - it helped a bit but I will have to do some work on that area.
First up this car went really well clocking under 5 secs on all lanes at HSC except Black where the best time was in the 5.2 sec range.

Now some Pics: -

: Top shot with running gear.; IMG_2888.JPG (53.63 KiB) Viewed 14622 times

: Bottom shot with running gear.; IMG_2880-1.JPG (53.48 KiB) Viewed 14621 times

: Front Wheel set-up - JK wheels set up independently on an free running axle.; IMG_2889-1.JPG (49.3 KiB) Viewed 14621 times

: Front detail showing pan attachment via .032" wire and the pin rattlers of .062' pin tubing inside .062" ID square tubing (drilled out to .078" for more rattle).; IMG_2890-1.JPG (64.66 KiB) Viewed 14622 times

: Rear end detail - pan attachment and rear rattlers. Bracket is JK modified by elongating the motor bearing and motor mounting holes to allow motor to sit level with bottom of chassis.; IMG_2893-1.JPG (64.79 KiB) Viewed 14620 times

: Top shot showing the attempt at a damping system - more to do here re the damping.; IMG_2895.JPG (87.67 KiB) Viewed 14621 times

: Da Spring and rear pan mounting system.; IMG_2900.JPG (44.12 KiB) Viewed 14619 times

: Bare chassis from bottom - all brass sections are K&S .062" brass strip.; IMG_2902.JPG (62.29 KiB) Viewed 14621 times

: Bare chassis showing front detail - front wheels are supported by bent up .062" X .500" K&S brass strip.; IMG_2903.JPG (48.54 KiB) Viewed 14619 times

SlotBaker · Post by **SlotBaker** » Wed Mar 04, 2009 3:34 pm

Mark,
Nice build, with the (now) trade mark 'spring'.

Am I ok to copy to AR website?

Thanks for posting.

chadly · Post by **chadly** » Wed Mar 04, 2009 6:57 pm

Hi from Perth.
I am very interested in this retro thing, i love building and racing my own equipment. I'll try and get some pics up of my own design laser cut Group 12 chassis.

Retros look the goods for me though (brass and wire)!

What/where are the pivot points for this chassis? what exactly are the requirements for the rear end? Can we get away with just having the rear motor/axel bracket with nothing else attached? Are they (the pink PSE) the best gears to use? can you get other types of gears?
soooooooo many questions.
I think it is best answered in person but i'd like to have a go at making one myself. I might.........MIGHT be coming over later this year.

chadly · Post by **chadly** » Wed Mar 04, 2009 7:57 pm

drag cars

SlotBaker · Post by **SlotBaker** » Thu Mar 05, 2009 8:14 am

Nice frame chadly.
Looks like you will have no trouble building the retro frames.

I'm pretty sure that Mark hasn't used pivots in this frame, and has relied of rattle movement through the body mounting (& floating pin tubes), and torsion flex through the main frame, but I sure hope that Mark will chime in here if I've got that wrong.

As far as rear end goes, for the inline CanAm cars, there must be a 3 sided motor bracket used.

The fundamental aim for Retro is to simulate materials and ideas used to scratchbuild frames prior to 1969.

Here are the current regs that we run with;
http://aussieretro.ascra.com.au/ca-regs081002a.pdf

The home of Retro racing is D3, and IRRA in the USA, and you can get more here;
http://slotblog.net/index.php?showforum=132

We follow the IRRA guidelines as it has been set up for universal use, and can be adjusted for local requirements.

"D3" is specifically SoCal, and their rules must be adopted 100% if you want to run under the "D3" banner.

Post by **Mark Fox** » Thu Mar 05, 2009 12:04 pm

SlotBaker wrote:Nice frame chadly.
Looks like you will have no trouble building the retro frames.

I'm pretty sure that Mark hasn't used pivots in this frame, and has relied of rattle movement through the body mounting (& floating pin tubes), and torsion flex through the main frame, but I sure hope that Mark will chime in here if I've got that wrong.

Steve you are correct re the mounting - the rattling pin tubes provide almost all of the actual separated movement with a little movement of the pan assembly provided by flex at the mounting point at the front which is 0.032 wire soldered directly to the front "crash bars" and then to the pans.

Steve you are welcome to post to AR site.

Lovely looking drag car Chadly - as Steve said you will have no trouble building for this class - hope we catch up some day.

chadly · Post by **chadly** » Thu Mar 05, 2009 4:30 pm

Sorry bout not sticking to just Retro, but i just love anything home built - drag, HO, 1/32, 1/24, 1/24 scale, electronic controllers. I'm biting at the bit to get my chassis photographed now. I left my USB-phone conector in Adelaide when i was over there.

The torsion chassis movement works well. I incorporated it into one of the first GTP 12 chassis' i built and used it to win the '95 WA state championships. I didn't use the idea again until my recent GTP 12 spring steel jobs, this time with the rattler pin tubes. I tried the torsion method again because thats what the slick 7 GTP 12 chassis' were using. The cars seem alot more "biteier" at speed. Having said that, Brad Bennett put together one of my chassis' using floating pans (lots of travel in all directions) and its almost as good.

Does anyone actually have any restrictions on hand controllers (apart from the obvious). You know, like "must be commercially available" or "must be the old resistor type"

SlotBaker · Post by **SlotBaker** » Thu Mar 05, 2009 5:07 pm

chadly wrote:(apart from the obvious)

Only restriction that I'm aware of, is that the controller must not add any voltage, in any way to the track.

Post by **stoo23** » Thu Mar 05, 2009 8:16 pm

chadly wrote:Hi from Perth.
Hi Chadley Welcome to the Forum.
Great to hear there is still Racing going on in WA !!

I am very interested in this retro thing, i love building and racing my own equipment. I'll try and get some pics up of my own design laser cut Group 12 chassis.
That's a Pretty cool looking 12 chassis! and Damn Fine Drag chassis/car !!

Retros look the goods for me though (brass and wire)!
Yep !!

What/where are the pivot points for this chassis?
Well, 'Fox', has already 'described' that,..BUT, the Style of Retro Car/Class we are currently running, the Actual 'Hinge' movements are 'Limited', as can be see from the rules.
The US D3/IRRA rules Also 'define' a number of Other Classes, that use various limitations or lack of regarding possible Chassis derivations and Motor choices.

For the Initial 'Retro/D3' concept, see here;http://socald3.com/
Some Great Names there, from the Huge past of US slot racing.

The idea , especially so far here, like in SoCal at BPR, is to Keep it Simple,..and So Far, it Sure seems to be Working.

Although initially the rules seemed somewhat limited chassis design Wise, I would Honestly say it HJas Not been, as there are Many different designs already running Here let alone in the States.

The choice of 'Sealed' Simple affordable Motors is I think a VERY Important aspect of what has made the racing So good.

what exactly are the requirements for the rear end?
Yeah, as Slotbaker said, a Three sided motor bracket, which Doesn't actuallyt Have to 'Support the Rear Axle, But Must extend to Toiuch Whatever Housing Is supporting the axle. We are Not running Ball Bearings, which although being a BB supporter myself, has NOT proven to be an issue, Fox and Myself are Both running the Slick7 Bushings and so far I would have to say they are proving to be Excellent!!!!

Can we get away with just having the rear motor/axle bracket with nothing else attached?
????

Are they (the pink PSE) the best gears to use?
Good Question?!!,..lol, There Are also the Black Cox clone style, I think maybe Champion ?

can you get other types of gears?
??,..Yeah!,..I would have thought a Good Drag Racer would have Known That !!,..lol
Sonic make a Range of 64 pitch Crowns, (For Drag Racing!), that quite a Few people are using overseas,..Some have even run Slot.it or Similar 1/32 scale crowns,. The PSE ones Are a Wee Bit 'O a Hassle', as they are 1/8th and we run 3/32,..DOH !!. so one spends a bit of time 'Sleeving' Gears,..
I think Perhaps even Valiko also Make some crowns.

Worth noting also is the fact that one can utilise either a Standard 'In-Line' style Motor Bracket, or What has become known as a 'Hypoid' bracket, (the terminology Not actually being correct), which Has the Motor Flat on the deck, thereby Making the Motor shaft 'Lower' that the Axle, which with the Angled Pinions, like the GT1 & ARP, allows you to theoretically get as smooth a Mesh .
Sure Works OK and a Very Smooth and Silent Gear Mesh IS Possible.
Perhaps on a Very Fast Track an Offset setup may Lose some Power through extra 'Friction'.

soooooooo many questions.
So Little Time !!!,..lol

I think it is best answered in person but i'd like to have a go at making one myself. I might.........MIGHT be coming over later this year.

Why NOT !!??,...lol

Have a Look Here;http://slotblog.net/index.php?showtopic=7441 also if you have a Good look around Generally, on SlotBlog, I think you will find a Wealth of Really Interesting Stuff !! Some Really Great Builders and Racers there !!
and also here; http://albums.phanfare.com/3996070/2009/
for 'Inspiration' whatever, lol
Keith Tanaka's site Really is Very Good and worth having a good look at, plenty of Great 'Detail' chassis pics and more.

Come on Over !! Always Welcome,..Plenty of Fast 'Loaners' even if Ya Don't have a car with Ya !!

So,..Where the Heck Can,..or Do you Race ?? Got any Pics/Links ??

Tell us all More !!

Cheers,
Stoo

chadly · Post by **chadly** » Fri Mar 06, 2009 3:09 pm

Not any real quick/light 24th racing, like i was brought up on. I race alot of HO's and plastic 1/32 stuff (all underground/backyard stuff).
The really quick HO's gets me my "lets go fast" fix, but we also race the older non-mag traction T-jet cars which are a very fun and inexpensive (most of the time) way of racing. Go to www.ravenspeedway.webs.com and you can see the HO track i am currently building myself.
With the 1/32nd stuff, the guys aren't really into modifying cars, ect. Its more about drinking beer, watching dvd's (some about cars) and having a bit of fun. Syd Miller, who has the MJK distributorship here in WA, has just built a new little track. It is fast (right up my ally) which has sparked some interest (particularly because i'm all of a sudden 3/10ths quicker than them). There is talk of getting some international 32 and possibly some scratchbuilt 24th racing happening.

I am really interested in metal inline gears. We use the sonic 64 pitch gears on most drag cars but i think they only go as low as 45 tooth. The plastic grey things are rearly straight and some are totally stuffed new! The pink PSE gears are ok (do you know you can get alloy gear savers which stop them from flexing). The plastic 1/32 gears are ok (50 pitch, not 48). I have seen some nice metal 3/32 inline gears but they were on some 1/32 cars from the 60's, i'm sure someone still makes them though.

tty later, i gotta run.

chadly · Post by **chadly** » Tue Mar 24, 2009 5:29 pm

It took me a while, but i promised. The pics are not great quality either. They are mainly lazer cut GTP 12 chassis', but i'm sure you could get something out of them.

more later......