Physics and the Pinewood Derby video

[cozybldr]

I was watching the video "Physics and the Pinewood Derby" just to see if there was anything that he may have covered that I didn't know. Hey, you never know, he might have something. He made mention of a couple takeaways that I saw.

1 - The wheels are life limited to 20 runs. For some reason, I think that is suspect considering the tuning you guys do and the racing you do.

2 - Tap the bores with a 4-40 tap. This is one that I have heard before but that it takes a left and a right tap. Now, I have to take exception with this because I have never heard you fast racers doing this. I know most of us do the polishing of the bores and seem to do well, graphite or oil. What is the experience of the group with tapping? I suspect that against normal wheels it is an advantage, but not against the polished axles and bores we do.

3 - Reducing the wheel diameter. He takes all of his weight off the outside making his wheels smaller. For some reason, this is suspect to me. I always thought that the larger the diameter the wheel, the less pressure and rolling resistance. Maybe I am wrong?

4 - I outright laughed when I saw the wheel alignment and his axle hole drilling methods. Nuff said.

Other than that, it was not a bad video and I liked the math and science for the kids to learn. Maybe you could get lucky and build a car that outruns DD4H, but I somehow doubt it. I mean, really, free hand drilling the axle holes on the table with a Dremel?? Then using setscrews to align each axle? I am so glad I found the Block.

Rick

 

[DNA RACING]

i am not familiar with that vid, but there are a ton of guys out there who found stuff that worked for them, on a scout or local parents race. this guy may actually get those methods to work for him. but the real trial by fire would be for him to send his cars to a league race. I think he would be getting smoked, ALOT !
2 years ago when i was racing with another league, I contacted "coach" from coaches secret dry lube. after all his braging about how his lube was much faster than oil and he held the world record for PWD cars I called him on his claim. He came up with excuses and never did show.....If you want the fastest and best building "tips and tricks" you are in the right place right now.

 

[PxTx]

The taping of the wheel bore to minimize contact area intriges me. Is there a previous discussion thread on this?

 

[cozybldr]

Tapping a thread form into the wheel bores is an old speed trick. It does 2 things: reduce the bore inside the wheel and supposedly reduce friction because of less surface area contact. I have never heard of any of the top racers using it. I might be wrong, but everybody I know is polishing the bores. It reminds me of truth being stranger than fiction. Old VW Bug roller bearings cranks were supposed to reduce friction losses in the bearing area. Science proved that the plain bearing cranks actually had less friction because the crank was floating on a pressurized oil film. That is why I asked the question. My understanding of the tap is you need both a left and a right hand tap to get it to work right. Yet, I haven't seen or heard any League racers using it.

 

[Chief]

[font="times new roman, times, serif"]It was my experience with the tapping of the wheels that it did work, however it worked to well. I also had to try about four different styles of axles with them as well. What it did for me was it made the wheels unscrew if you will from the body of the car, BUT, it screwed the wheels

into the axle head which actually slowed the car, i tried it with graphite and oil both and same results. End result, new axles and new wheels and I had to start from step one all over again. Also I have a worthless left handed tap now too.[/font]

 

[Kinser Racing]

Tapping a thread form into the wheel bores is an old speed trick. It does 2 things: reduce the bore inside the wheel and supposedly reduce friction because of less surface area contact. I have never heard of any of the top racers using it. I might be wrong, but everybody I know is polishing the bores. It reminds me of truth being stranger than fiction. Old VW Bug roller bearings cranks were supposed to reduce friction losses in the bearing area. Science proved that the plain bearing cranks actually had less friction because the crank was floating on a pressurized oil film. That is why I asked the question. My understanding of the tap is you need both a left and a right hand tap to get it to work right. Yet, I haven't seen or heard any League racers using it.

You haven't heard about it because it doesn't work. /images/boards/smilies/smile.gif

 

[Quicktimederby]

Tapping a thread form into the wheel bores is an old speed trick. It does 2 things: reduce the bore inside the wheel and supposedly reduce friction because of less surface area contact. I have never heard of any of the top racers using it. I might be wrong, but everybody I know is polishing the bores. It reminds me of truth being stranger than fiction. Old VW Bug roller bearings cranks were supposed to reduce friction losses in the bearing area. Science proved that the plain bearing cranks actually had less friction because the crank was floating on a pressurized oil film. That is why I asked the question. My understanding of the tap is you need both a left and a right hand tap to get it to work right. Yet, I haven't seen or heard any League racers using it.

You haven't heard about it because it doesn't work. /images/boards/smilies/smile.gif

+1

 

[ljo]

That dvd is bogus.