What's new
By:
Filters

Hotwheels Racing

Rooney77

Rooney77

Bearded lady
Joined
May 20, 2020
Member Number
494
Messages
313
Loc
TX
I work with a lot of nerds, not surprising given the field I'm in. Anyway, one of my coworkers built a badass hot wheels track to race on with timing and everything. My son (10yrs old) has jumped off the deep end on it and is now trying to figure out what makes the cars faster.

Me being the engineer, I'm trying to use this to explain how weight effects them since it's a slanted track, friction of the wheels on the track and wheel to axle friction.

A buddy has the faster car at less than a second. To beat him I'm hunting a heavy car with the skinniest wheels I can find.

Someone here has to know of something that meets that spec. Narrow wheels like those on the front of a gasser and heavy. Anything? I'd like to prove to him how all these things effect the car.
 
Tractor Monger said:
Add lead
Click to expand...
I've busted a few apart to experiment with weights. There's definitely a line where it's too much. I've figured out that weight should be the last thing you play with. Wheel interaction with the track, wheel tracking, axle to wheel interaction all play more key roles.

We've run a few firetrucks that were pushing 60 grams but had wide wheels and they couldn't hang with the audi with better axles and tracking that weighed half as much.

It's been fun experimenting to figure it out. And I'm enjoying guiding him and watching him put it all together.
 
We've been doing the graphite thing and I'm gonna try polishing the wheels.

I'm just curious if anyone knows of a particular model that's got all 4 wheels narrow and is decently weighted?

I've got some replacement axles I'm looking to try but I'm trying to keep it looking as "stock" as possible.

My main goal is to teach my kid how to think his way through the issue by identifying the setbacks and figuring out solutions for them.
 
Rooney77 said:
We've been doing the graphite thing and I'm gonna try polishing the wheels.

I'm just curious if anyone knows of a particular model that's got all 4 wheels narrow and is decently weighted?

I've got some replacement axles I'm looking to try but I'm trying to keep it looking as "stock" as possible.

My main goal is to teach my kid how to think his way through the issue by identifying the setbacks and figuring out solutions for them.
Click to expand...

Use the same car as the fast guy. :homer:
 
align the tires to the track is something I remember being good for derby cars, make it so not all wheels touch the track for less resistance, we used tungsten for weight instead of lead since it was denser.
 
SLOWPOKE693 said:
Sand the tires down so only the width of a needle touches the ground. Graphite on the axles and lead in the nose. Done
Click to expand...
Does that work and does it go straight?

Thanks for the racing rabbit hole OP, glad I have kids to use an excuse:laughing:

if skinny is better, maybe pull these?

1000030536.jpg


www.target.com

2013 Jeep Wrangler Unlimited Moab Edition Gecko Green "Sport Utility" Limited Edition 1/64 Diecast Model Car by Auto World

Read reviews and buy 2013 Jeep Wrangler Unlimited Moab Edition Gecko Green "Sport Utility" Limited Edition 1/64 Diecast Model Car by Auto World at Target. Choose from contactless Same Day Delivery, Drive Up and more.
www.target.com www.target.com
 
We used to try to align them, then set 1 wheel higher so it didn’t touch the track. Less friction with 3 wheels. We had someone do that with the block and was very quick with no other mods. We used to have an adult pinewood derby the week after the kids cause the track was setup.
 
We had some track with a motor that would speed them up and fling them off the track if they weren't just right, we used the little crack scale and made some charts and taped coins to the bottom of them to find the sweet spot

Ymmv



And I'd shave the tires down, from the inside out, ie, narrower tires, same track width
 
cervelorod said:
We used to try to align them, then set 1 wheel higher so it didn’t touch the track. Less friction with 3 wheels. We had someone do that with the block and was very quick with no other mods. We used to have an adult pinewood derby the week after the kids cause the track was setup.
Click to expand...

That's where I learned to sand the tires down so that there was just a rib in the center touching the track. It beats the 3 wheel trick because it's even less friction than doing that. I won a couple pinewood derbys back in the day with help from my motorhead uncle. :smokin:
 
Also, if you can get lead ahead of the front axle put it there. Add lead until it's so heavy it lifts the rear tires and then remove just enough to put them back on the ground. That trick removes even more friction between the track and wheels and also "pulls" the car down the track.
 
grumpy356 said:
Any pics of the tracks?
Click to expand...

I'll get some. It's impressive.

SLOWPOKE693 said:
Also, if you can get lead ahead of the front axle put it there. Add lead until it's so heavy it lifts the rear tires and then remove just enough to put them back on the ground. That trick removes even more friction between the track and wheels and also "pulls" the car down the track.
Click to expand...

From my experimenting, the weight needs to be centered. Too far forward and the ass wags, especially in the transition from incline to flat. Too far back and the same effect just in reverse.

We are timing down to 3 decimal places so it's getting stupid competitive, especially for a group of adults.
 
Rooney77 said:
I'll get some. It's impressive.



From my experimenting, the weight needs to be centered. Too far forward and the ass wags, especially in the transition from incline to flat. Too far back and the same effect just in reverse.

We are timing down to 3 decimal places so it's getting stupid competitive, especially for a group of adults.
Click to expand...


How steep is the track?
 
SLOWPOKE693 said:
lead in the nose. Done
Click to expand...
That certainly depends on the track and the “rules”. Pinewood derby is weight all the way in the back. It increases the potential energy because the weight is stored higher on the track and falls longer. Very noticeable.

Curved tracks can certainly change that.

3-wheel motion helps with friction and steering. Less wobbles and tracking. You can usually ride a rail for steering.


Edit: After seeing that track, definitely weight in the back. Car balance over the rear axle.
 
Last edited:
NPKennny said:
That certainly depends on the track and the “rules”. Pinewood derby is weight all the way in the back. Increases the kinetic energy because the weight is higher on the track and falls longer. Very noticeable.

Curved tracks can certainly change that.

3-wheel motion helps with friction and steering. Less wobbles and tracking. You can usually ride a rail for steering.
Click to expand...
Riding a rail is an increase in friction. So you'd need to be sure the roi you got from the lack of tracking made up for the increase in friction of rubbing the rail.

It's a game of give and take. Finding the right combo.
 
Rooney77 said:
Riding a rail is an increase in friction. So you'd need to be sure the roi you got from the lack of tracking made up for the increase in friction of rubbing the rail.

It's a game of give and take. Finding the right combo.
Click to expand...
wobble scrubs speed, so a light rail ride is better than a wobble, and three wheels are faster than four
 
Stingray said:
wobble scrubs speed, so a light rail ride is better than a wobble
Click to expand...
Agreed depending on the degree of wobble. And if tracking is off enough that you're steering into the wall then it's a negative impact. Also, wobble on narrow wheels has less effect than wider wheels. There's no real rules of thumb here.

Also, if it's open wheel and the wheels themselves are riding the rail then the impact is amplified.

It's crazy how seemingly nonissues become issues at this scale. You can't apply 1:1 logic to it.
 
Rooney77 said:
Agreed depending on the degree of wobble. And if tracking is off enough that you're steering into the wall then it's a negative impact. Also, wobble on narrow wheels has less effect than wider wheels. There's no real rules of thumb here.

Also, if it's open wheel and the wheels themselves are riding the while then the impact is amplified.

It's crazy how seemingly nonissues become issues at this scale. You can't apply 1:1 logic to it.
Click to expand...
Hot Wheel scale is not 1:1:flipoff2::flipoff2:

Following...
 
You must log in or register to reply here.
Top Back Refresh