New Drive (CanAm) for BTR

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Mark Fox
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New Drive (CanAm) for BTR

Post by Mark Fox »

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-)

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neiljb
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Re: New Drive for BTR

Post by neiljb »

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
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Re: New Drive for BTR

Post by Mark Fox »

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-)

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dtslot
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Re: New Drive for BTR

Post by dtslot »

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

Post by brady »

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

Post by Greg Erskine »

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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Re: New Drive for BTR

Post by Mark Fox »

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-)

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Mark Fox
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Re: New Drive (CanAm) for BTR

Post by Mark Fox »

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-)

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Greg Erskine
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Re: New Drive (CanAm) for BTR

Post by Greg Erskine »

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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Re: New Drive (CanAm) for BTR

Post by Mark Fox »

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-)

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Greg Erskine
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Re: New Drive (CanAm) for BTR

Post by Greg Erskine »

Thanks Mark,

I understand. :)

regards
Greg
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