New Drive (CanAm) for BTR

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Mark Fox
Posts: 225
Joined: Mon Feb 09, 2009 10:11 am
Location: Balmain, Sydney

New Drive (CanAm) for BTR

Postby Mark Fox » Wed Jun 28, 2017 2:53 pm

Hi
Here is something that I have been meaning to finish for a while and I finally got to test it at HSC 'BiG TracK' last night.

It's mainly wire - big wire as you can see - a lot of .078, .093 and some .125 for the front axle struts - it's a b----r to bend!

The body is mounted onto a floating raft - it doesn't move much though as I believe that it is the actual weight separation that makes these things work rather than the actual way the weight is separated and moves - just my thoughts.
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Weight came out exactly what I was aiming for - as a matter of interest if you have never measured it a completed Retro CanAm will weigh in at : Chassis Weight including front axle and rear bearings plus 50 grams give or take a couple of grams with slight differences in running gear.
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It works a treat and was cutting very smooth 5.4's on the fast lanes - a little out of sorts on the drivers turn on Red and White but some tuning to b done.
Last edited by Mark Fox on Fri Jun 30, 2017 9:20 am, edited 1 time in total.
Regards - Mark 8-)

"Do Less with More Focus"

neiljb
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Joined: Sun May 18, 2014 6:44 pm

Re: New Drive for BTR

Postby neiljb » Wed Jun 28, 2017 5:38 pm

Thanks for sharing again. You must have used an hydraulic press to bend the wire that supports the front axle!!
Neil

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Mark Fox
Posts: 225
Joined: Mon Feb 09, 2009 10:11 am
Location: Balmain, Sydney

Re: New Drive for BTR

Postby Mark Fox » Wed Jun 28, 2017 6:02 pm

neiljb wrote:You must have used an hydraulic press to bend the wire that supports the front axle!!

No but I had to re-anchor the vice to my table and I thought I was going to break it :roll:
Regards - Mark 8-)

"Do Less with More Focus"

dtslot
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Joined: Tue Mar 12, 2013 7:34 pm
Location: NORTH RICHMOND NSW

Re: New Drive for BTR

Postby dtslot » Thu Jun 29, 2017 11:42 am

Nice one Mark,,,,,,,,super strength and light and best of all its pretty,,,,,Its an artwork
Darryl

brady
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Re: New Drive for BTR

Postby brady » Thu Jun 29, 2017 11:58 am

Hi Mark.I am very interexted to see how this one goes.I built a couple very similar in desig n for Raceworld a couple of years ago.I gave one away,it worked great,the other one I kept wasnt so hot.Nice clean build as usual mate.Regards Brad.

Greg Erskine
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Re: New Drive for BTR

Postby Greg Erskine » Thu Jun 29, 2017 12:44 pm

Thanks for posting Mark,

I would not have thought of going that thick of wire on a chassis. Very interesting and opposite to what they seem to be doing in the states.

BTW: I am enjoying and appreciate all your posts and probably don't thank you as I should. :)

regards
Greg

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Mark Fox
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Location: Balmain, Sydney

Re: New Drive for BTR

Postby Mark Fox » Thu Jun 29, 2017 8:31 pm

Thanks for the kind words guys.

The basic design is as as old as and I'm sure the design certainly went well on the King Brad.

Re Greg's comment:-
Greg Erskine wrote:I would not have thought of going that thick of wire on a chassis. Very interesting and opposite to what they seem to be doing in the states.

The only thick wire of any actual consequence here is the 078 rails - all the rest really just replace Brass plate to a degree excepting for the front axle struts.

I have built quite a few multi-rail cars as well and they go fine but have a look on Slotblog at some of the CanAm cars built and inspired by Bryan Warmack - 0.125 rails albeit flattened - go figure 8-)

A lot of decisions I make in a build are all about expedience.

For example in this build the rails are .078.
The tubes holding the raft/outrigger 'pans' have a .015 wall thickness.
This means that the bottom of the outrigger supports are .093 off the deck.
Bingo - just use .093 wire to construct the pans - strong and no mucking around to get the levels right.

QED
Regards - Mark 8-)

"Do Less with More Focus"

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Mark Fox
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Re: New Drive (CanAm) for BTR

Postby Mark Fox » Tue Aug 01, 2017 6:26 pm

Well I used this car at SSME to finish = 2nd with Darryl just behind Steve K and it was a really fast car setting fastest laps on 5 of 6 lanes but it seemed to have a lot of body vibration which I think came from the rattling body 'raft'.

Given that it showed real potential I decided to go back to a hinged pan type of layout which incidentally was what I planned originally before I got carried away.

Anyway here she is with hinges and a bit more rear bracket bracing.

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Regards - Mark 8-)

"Do Less with More Focus"

Greg Erskine
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Re: New Drive (CanAm) for BTR

Postby Greg Erskine » Wed Aug 02, 2017 9:14 am

Thanks for keeping us updated!

If I could ask a few question....

Do you set your front wheels to permanently touch the track?

How many thou do you space your guide?

regards
Greg

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Mark Fox
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Location: Balmain, Sydney

Re: New Drive (CanAm) for BTR

Postby Mark Fox » Wed Aug 02, 2017 9:58 am

Greg Erskine wrote:Do you set your front wheels to permanently touch the track?

Absolutely - this is critical for these cars. I take the body off the car and roll it around the track on the corners and on all of the lanes to ensure the front wheels are turning.
Greg Erskine wrote:How many thou do you space your guide?

The guide is spaced such that the front wheels are always touching as explained above plus an extra 10 - 20 thou. When you push down on the guide post (body off) the rear wheels should lift off the track as the car will use the front wheels as a fulcrum if the set up is correct.

Hope this makes sense - happy to discuss when I next see you.
Regards - Mark 8-)

"Do Less with More Focus"

Greg Erskine
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Joined: Fri May 05, 2017 5:20 pm

Re: New Drive (CanAm) for BTR

Postby Greg Erskine » Thu Aug 03, 2017 8:35 am

Thanks Mark,

I understand. :)

regards
Greg