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... and a foot-operated brake too!

Posted: Sat Apr 01, 2006 7:33 pm
by Teeeman
After 10 minutes of deliberation, and 30 minutes of work, it turned out to be rather easy to make the brake foot operated (have the option to easily switch back to hand op if this brings the stink once we try it).

-Terry


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Re: ... and a foot-operated brake too!

Posted: Mon Apr 03, 2006 5:31 pm
by clemsontigerfanatic
My car building days are now over. Race was April 1st. We had some steering wheels and foot brake cars. They are the way to go.
Our race had several wrecks (one car turned on its side) .

If I had to do over again I would have done at least a steering wheel.
Actually foot brake too.
I had one very nervous mom. After watching some of the wrecks I can't blame her.

Re: ... and a foot-operated brake too!

Posted: Mon Apr 03, 2006 8:03 pm
by Teeeman
fanatic: Did I read correctly that you did in fact build some wheel steered cars with footbrakes in the past? If "yes", do you have pics of how you did them?

-Terry







The general consensus on our car design is that we may get put into Unlimited... that is the opinion of 1 person, nobody else has spoken up, and the race organizers don't answer my e-mail as usual.

I have given it a lot of thought... per the rules, the only firm requirements we have are wheel diameter, width, axle/axle spacing, and total length.

The rest is open to interpretation, and we did a LOT of interpretation with the rest... but we strictly adhere to the core rules.

I will be "armed for Bear" if they try to outlaw us from Trophy class come Saturday... I'll have the rules and one well-prepared argument.

-Terry

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 6:39 am
by clemsontigerfanatic
We don't have that many cars in our races. Steering wheels and foot brakes don't make the car faster only safer. I don't have any pitcures sorry.

I have not built a steering wheel or foot brake car. I don't seem them as being that hard to do though. Just some pulleys and some cable or PVC pipe. I've seen both. I do like having a plan to go by though. I built pretty much by the Bear Book drawing.

I did observe the larger wheel cars seemed faster.

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 9:49 am
by Teeeman
Got a reply!

We are "go for Race!" with our new design, our local organizers only focus on the wheels, and we are legal.

I'm curious if upgrading from 8" to 10" Commtech wheels will help our speed (even asphalt has quite a surfce roughness, the larger wheels will require more inertial energy to spin BUT will traverse imperfections better).

We actually upgraded just to have larger bearing IDs so we could use thicker axles... not for performance reasons.


All the fancy-smancy overkill we put in our design was for but one thing: Safety!
Well, perhaps moving the seat so far to the rear was for performance only, but even the lofted wheel is there to give the car smooth steering (control).

I'll try to post up some pics in 3 days or so when we get this car together... I want to focus on the improvements to the seat and seatbelt especially.
And hopefully show the steering in action (if our 3/8 ply swivel plate won't side-flex too much in use).

-Terry

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 1:33 pm
by Smell of pine
We still have foot controlled steering, but used a self-centering system. We also have a very low center of gravity and a ramp with a very smooth transition.

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 4:01 pm
by Teeeman
Smell of pine wrote:We still have foot controlled steering, but used a self-centering system. We also have a very low center of gravity and a ramp with a very smooth transition.
Is the self-centering system like a caster (utilizing mechanical trail)?

-Terry

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 7:07 pm
by Smell of pine
Slightly, but it also includes a double pigtailed spring that wraps around the bolt, and is adjustable. I have a couple other ideas, but we're going this route this year.

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 7:13 pm
by Teeeman
Smell of pine wrote:Slightly, but it also includes a double pigtailed spring that wraps around the bolt, and is adjustable. I have a couple other ideas, but we're going this route this year.

All you need now is a damper and you will quite a nice working solution to standard steering :)

One of our nicest Pack Cubmobiles uses a double "screen door" spring (long coil springs you can buy at Lowes and other hardware stores for doors). It simply has one per side, pulling in opposition to each other (they run along the front axle, parallel, and attach to the center beam).
It is not very effective, though, needed heavier springs and greater pre-load on them... but it is the same idea in a less complicated fashion than what you did, I think.


-Terry

Re: ... and a foot-operated brake too!

Posted: Tue Apr 04, 2006 10:23 pm
by Smell of pine
Actually one of my other ideas involved a sort of damper. ;) Adjustable at that.

Re: ... and a foot-operated brake too!

Posted: Thu Apr 06, 2006 8:10 am
by clemsontigerfanatic
Teeman
One of the cars I saw this year had a hinged pushbar so that it swings down after the boys let go. You know how important aerodynamics is :lol:

Re: ... and a foot-operated brake too!

Posted: Thu Apr 06, 2006 1:03 pm
by Teeeman
clemsontigerfanatic wrote:Teeman
One of the cars I saw this year had a hinged pushbar so that it swings down after the boys let go. You know how important aerodynamics is :lol:

oh yeah.... oh yeah.....


we are going to be assembling tomorrow, it looks like... after 2 late nights in the garage and an offer for help from my neighbor tonight, we just may make Saturday's race (unpainted, unsanded).

Grrrrrr... we really needed those other 5 weeks to make this a comfortable, fun project...


-Terry

Re: ... and a foot-operated brake too!

Posted: Tue Apr 11, 2006 1:50 pm
by Smell of pine
Teeman,
Did you guys race Saturday? How did it go? The clock seems to be ticking quite rapidly for us. About 6+ weeks away, and PLENTY to do.

Re: ... and a foot-operated brake too!

Posted: Tue Apr 11, 2006 2:44 pm
by Teeeman
Yep, I put vids up I thought... (I'll make sure they are posted)...


plan to put the vid of my son up soon, but I went to bed early last night...
real early...


-T

Re: ... and a foot-operated brake too!

Posted: Tue Apr 11, 2006 2:49 pm
by Teeeman
Smell of pine wrote:Teeman,
Did you guys race Saturday? How did it go? The clock seems to be ticking quite rapidly for us. About 6+ weeks away, and PLENTY to do.


Here's the link to the post with videos:

http://derbytalk.com/viewtopic.php?t=1857


-T