Cant do that!

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Nice! Speed Bump.

I am very curious to know your findings as well.

I can speculate that the reason BR decided to post this riddle on this particular topic is because of his distaste for the rears touching the rail.

Hi Opa,

I really like that phrase "point of diminishing returns"

I drew it up like you said and understand where you are coming from with the wheel bore but I was searching for a different diminishing number.

The space between the rail and the wheel will start to diminish after 5.9*

This to me would indicate the very upper end of the scale for the rears.

The best number is probably in there somewhere, and dependent on many factors such as the builders preference.
 
laserman said:
Hi ODD,

I think that if a flat axle will not want to migrate, but a 3* axle will want to migrate, then at a 6 degree angle it will want to jump out there quicker.

The body should probably be angled to match the angle of the inner bore at 90* so that the gap can be the same at any angle. (I think)

The only reason that I can think of that this is not talked about more often here is:

One would need a pin slightly smaller than 3/16" diameter under the Silver Bullet in order to achieve it.

I think 3/16" comes out to about 6.5* so I am going to look for a long pin that is a tad smaller.

Probably the fellas with bigger set ups do it all the time.
Click to expand...

I wouldn't make the body side 90º to the bore, make it a little less to minimise the contact area if it rubs.

You're right Joe. I don't like when the rears rub the rail at all but that's not why I try different cants.

6º might be a little too far SB, but my two fastest SS cars so far are both "not three degrees".
 
bracketracer said:
laserman said:
Hi ODD,

I think that if a flat axle will not want to migrate, but a 3* axle will want to migrate, then at a 6 degree angle it will want to jump out there quicker.

The body should probably be angled to match the angle of the inner bore at 90* so that the gap can be the same at any angle. (I think)

The only reason that I can think of that this is not talked about more often here is:

One would need a pin slightly smaller than 3/16" diameter under the Silver Bullet in order to achieve it.

I think 3/16" comes out to about 6.5* so I am going to look for a long pin that is a tad smaller.

Probably the fellas with bigger set ups do it all the time.
Click to expand...

I wouldn't make the body side 90º to the bore, make it a little less to minimise the contact area if it rubs.

You're right Joe. I don't like when the rears rub the rail at all but that's not why I try different cants.

6º might be a little too far SB, but my two fastest SS cars so far are both "not three degrees".
Click to expand...

Hi Stephen,

Oh yeah! This riddle keeps getting better and better.
Please give me three guesses before posting the answer.
"Why do you try different cants?"

I am a very simple creature that has difficulty imagining beyond the realm of a static builder, so I only have one guess at this time. Given more time I am sure I can come up with others.

Is it to maximize the width of the base to create a more stable platform?

Does anyone know what those fellas that play wheelchair basketball have for a cant?

Thanks.
 
laserman said:
I am a very simple creature that has difficulty imagining beyond the realm of a static builder, so I only have one guess at this time. Given more time I am sure I can come up with others.
Click to expand...

I have seen enough of your work to know that statement is crap. You are a highly imaginative and creative person!
 
Ha! Thanks Stephen,

I guess it was crap since simplicity is something I have fought against for about 5 years now.

Louie the 14th has been more to my taste lately, but I used to be a big fan of the Bauhaus.

However, the 4th dimension is a hole new animal to me and I am enjoying unraveling it's mysteries.

Ok! second guess.

I will try to make this one my "far out" guess.

edit: Please skip that guess.

Thanks again,
 
Ok. Here is my guess from what I know of BR

It has something to do with the contact area between the outer hub (with step removed),
and the head of the axle.

This would have to be the outer limits of my left hand side of the brain thinking.

From here on the guesses may get a bit more unlikely.

Thanks
 
Nope. That last guess makes no sense either. I think.
It must be the wheels migrating quicker and staying there with more force.
 
OK Stephen,
I give up.
Why is it that you like more than 3* cant?
I am fully expecting a punch line here.
It is amazing how many nuances can be found with a block of wood, 4 nails, and a few discs.
It reminds me of chess. Simple rules but an infinite number of possible continuations.
 
After a certain point having the wheel that canted it will lose forward speed because the wheel wants to travel in an arc in the direction it is leaning. Take a coin and roll it on a flat surface. It will roll in a straight line but once it starts to tilt the path of least resistance sends the coin traveling in a curve. Having that on top of the increased pressure the outside of the bore to the top of the axle and the inside edge of the bore to the bottom of the axle increases with the angle as the axle holds the wheel from going in the direction it wants to roll.
 
Aww man. Now that is a good point too!

I feel like I did when I was 12 years old watching the presidential debates.

The first guy would speak and I would say "now that makes sense".

Then the other guy and I would say "well, that makes sense too!"

At this point in life I realize that one guy (or maybe both) is just up there saying things everyone wants to hear.

When it comes to moving parts, things are still very murky for me.

It doesn't stop me from sounding off and chiming in.

Luckily the fellas here are very patient and gently steer me in the right direction.

Often times letting me believe that I came across the answer myself.

This is a really humble bunch here.
 
ngyoung said:
After a certain point having the wheel that canted it will lose forward speed because the wheel wants to travel in an arc in the direction it is leaning. Take a coin and roll it on a flat surface. It will roll in a straight line but once it starts to tilt the path of least resistance sends the coin traveling in a curve. Having that on top of the increased pressure the outside of the bore to the top of the axle and the inside edge of the bore to the bottom of the axle increases with the angle as the axle holds the wheel from going in the direction it wants to roll.
Click to expand...

But the coin in your example goes straight until it slows below a certain speed. What if that certain speed as it applies to a PWD car is after the finish line?

Some of us are assuming that 3º applies enough pressure between the outer hub of the wheel and the axle head to stabilize the back of the car optimally without producing too much friction.

Have you ever ran a car with 1-1.5º of rear cant? On a bad run you can see and hear the rear of the body banging back and forth between the wheels. More cant would lessen the likelihood of that happening. I'm just saying that 3º may not be enough cant for your setup.
 
bracketracer said:
ngyoung said:
After a certain point having the wheel that canted it will lose forward speed because the wheel wants to travel in an arc in the direction it is leaning. Take a coin and roll it on a flat surface. It will roll in a straight line but once it starts to tilt the path of least resistance sends the coin traveling in a curve. Having that on top of the increased pressure the outside of the bore to the top of the axle and the inside edge of the bore to the bottom of the axle increases with the angle as the axle holds the wheel from going in the direction it wants to roll.
Click to expand...

But the coin in your example goes straight until it slows below a certain speed. What if that certain speed as it applies to a PWD car is after the finish line?

Some of us are assuming that 3º applies enough pressure between the outer hub of the wheel and the axle head to stabilize the back of the car optimally without producing too much friction.

Have you ever ran a car with 1-1.5º of rear cant? On a bad run you can see and hear the rear of the body banging back and forth between the wheels. More cant would lessen the likelihood of that happening. I'm just saying that 3º may not be enough cant for your setup.
Click to expand...

I'd love to see you prove it. I'm not being sarcastic or anything either, I really would love to see it. /images/boards/smilies/thumb.gif
 
Kinser Racing said:
I'd love to see you prove it. I'm not being sarcastic or anything either, I really would love to see it. /images/boards/smilies/thumb.gif
Click to expand...

Well, the car I built that way finished 24th at the last race in SS Pro (I was .002 and eight places behind you) with my less than stellar prep skills, with the time it ran I believe it would have came in second in both SS Nov or Am at the same race. It's the same car that I debuted with a win in SS Am back in August. If I ever get good at prepping I hope to move up!
 
bracketracer said:
ngyoung said:
After a certain point having the wheel that canted it will lose forward speed because the wheel wants to travel in an arc in the direction it is leaning. Take a coin and roll it on a flat surface. It will roll in a straight line but once it starts to tilt the path of least resistance sends the coin traveling in a curve. Having that on top of the increased pressure the outside of the bore to the top of the axle and the inside edge of the bore to the bottom of the axle increases with the angle as the axle holds the wheel from going in the direction it wants to roll.
Click to expand...

But the coin in your example goes straight until it slows below a certain speed. What if that certain speed as it applies to a PWD car is after the finish line?

Some of us are assuming that 3º applies enough pressure between the outer hub of the wheel and the axle head to stabilize the back of the car optimally without producing too much friction.

Have you ever ran a car with 1-1.5º of rear cant? On a bad run you can see and hear the rear of the body banging back and forth between the wheels. More cant would lessen the likelihood of that happening. I'm just saying that 3º may not be enough cant for your setup.
Click to expand...

This is good stuff Stephen

I know you had to run 4 on the floor with no cant for your boy's scout race.

This must have clearly demonstrated the obstacles one easily overcomes when canting, and the struggle one goes thru when it is disallowed.

If a little is good, then maybe more is better.

Since 1 bad run could set a racer back considerably in the standings, consistency would have to be of prime concern.

I for will be doing some extreme canting.

Besides that it looks more dynamic and visually stunning.
 

 3Phase -

That made me laugh and for that I give you a short video .... Have a wonderful day!!!

[video]https://www.youtube.com/watch?v=gASY7Lj5GPQ[/video]
 
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