Wedge cut or flat?

[Herbie33]

We are getting ready to start our second year of pinewood derby with the scouts. Last year we noticed most of the faster cars at the district were cut flat. Is there an advantage of flat cut rather than a wedge?

 

[Thinkin'Bout Racin]

We are getting ready to start our second year of pinewood derby with the scouts. Last year we noticed most of the faster cars at the district were cut flat. Is there an advantage of flat cut rather than a wedge?

Herbie,

I am not a Pro so take this advice with a grain of salt. I do feel however that I can offer sound advice in this area.

Physics dictate, if all else is equal, that a flat profile (thin to win), will be faster. This is simply because less air molecules need to be "pushed" apart with the thin design. If you are willing to use tungsten for weight, then there is no question that a thin car is faster.

If you are using lead for weight, then the issue is not quite as clear. A properly executed wedge car can win most dens, and even pack races. However, once you get to districts, the competition is tougher and therefore the thin design is more beneficial.

I am a bit of a glutton for punishment, so we built 6 cars for the open district race last year. Two of which were wedge designs. (I was working on a design for our scout workshop for this season) . The two wedge cars finished behind the 4 thin cars we had, but they both were slightly faster than all of the other cars including some well built thin cars with weight reduction. It appears that at least 4 of this years workshop cars are of the wedge design. Time will tell how they run.

 

[Skywalker Racing]

Thin to win! Wedge the leading edge to cut the air.

 

[Herbie33]

hERBIE,

I am not a Pro so take this advice with a grain of salt. I do feel however that I can offer sound advice in this area.

Physics dictate, if all else is equal, that a flat profile (thin to win), will be faster. This is simply because less air molecules need to be "pushed" apart with the thin design. If you are willing to use tungsten for weight, then there is no question that a thin car is faster.

If you are using lead for weight, then the issue is not quite as clear. A properly executed wedge car can win most dens, and even pack races. However, once you get to districts, the competition is tougher and therefore the thin design is more beneficial.

I am a bit of a glutton for punishment, so we built 6 cars for the open district race last year. Two of which were wedge designs. (I was working on a design for our scout workshop for this season) . The two wedge cars finished behind the 4 thin cars we had, but they both were slightly faster than all of the other cars including some well built thin cars with weight reduction. It appears that at least 4 of this years workshop cars are of the wedge design. Time will tell how they run.

hERBIE,

I am not a Pro so take this advice with a grain of salt. I do feel however that I can offer sound advice in this area.

Physics dictate, if all else is equal, that a flat profile (thin to win), will be faster. This is simply because less air molecules need to be "pushed" apart with the thin design. If you are willing to use tungsten for weight, then there is no question that a thin car is faster.

If you are using lead for weight, then the issue is not quite as clear. A properly executed wedge car can win most dens, and even pack races. However, once you get to districts, the competition is tougher and therefore the thin design is more beneficial.

I am a bit of a glutton for punishment, so we built 6 cars for the open district race last year. Two of which were wedge designs. (I was working on a design for our scout workshop for this season) . The two wedge cars finished behind the 4 thin cars we had, but they both were slightly faster than all of the other cars including some well built thin cars with weight reduction. It appears that at least 4 of this years workshop cars are of the wedge design. Time will tell how they run.

thank you for the advice!! Will definitely be doing a flat car this year. Also, we will be using tungsten. And I think most people could build a house in the amount of time my son and I have in one car, so I could not imagine building 6!! Lol

 

[Herbie33]

Thin to win! Wedge the leading edge to cut the air.

When you say "wedge the leading edge" do you mean the front top of the car or bottom? Or neither? Lol sorry I'm new to all these terms

 

[Skywalker Racing]

When you say "wedge the leading edge" do you mean the front top of the car or bottom? Or neither? Lol sorry I'm new to all these terms

We all were at one point; no worries.

Sand the front end till it comes to a point, so that you basically have a very thin wedge-shaped car. Some sand from both top and bottom, some sand top only. Up to you.

 

[Herbie33]

We all were at one point; no worries.

Sand the front end till it comes to a point, so that you basically have a very thin wedge-shaped car. Some sand from both top and bottom, some sand top only. Up to you.

Thank you, very much appreciated!

 

[Thinkin'Bout Racin]

And I think most people could build a house in the amount of time my son and I have in one car, so I could not imagine building 6!! Lol

Because we just found this site (last February) and wanted to learn, we did several different set-ups on the cars. Different WB's, different weighting, different profiles, some lead and some tungsten, different amounts of steer, some with fenders and some without. The wheel and axle prep was as consistent as I could make it. By doing all of this, it helped to steer me down the path of what works best and what might be the most efficient for a young Scout on a limited budget. We are just starting to apply some of what we learned on this years Cub's cars.

I believe this sport is all about learning ...one should never stop. If you do, you will literally get passed by.