Pinewood Derby ??
Feb 9th 2010, 2:38 am
#16
Unmitigated Gall
Joined: Dec 2006
Location: it's still too dark to tell
Posts: 16,162
Re: Pinewood Derby ??
Not me though, really!
I just went a little nuts that last time according to my wife...
But it was worth it!
Did you know that tungsten is about 1.8 times as dense as lead? This means a tungsten weight will be smaller than a lead one of the same weight. Smaller means more precise placement on the car which means you can more easily fine tune your weight distribution.... Tungsten weights run about $5 an oz. To think I had my boy using lead fishing weights or steel washers...
Actually for that last race we didn't use tungsten (Everywhere was out of it
) and we ended up using 300grain .44 magnum bullets that were lead with a copper jacket. Just the bullet, which I had a bunch of for reloading, not the whole cartridge case.
This link kind of explains it...
http://www.pinewoodpro.com/weight-sets.htm
I just went a little nuts that last time according to my wife... But it was worth it! Did you know that tungsten is about 1.8 times as dense as lead? This means a tungsten weight will be smaller than a lead one of the same weight. Smaller means more precise placement on the car which means you can more easily fine tune your weight distribution.... Tungsten weights run about $5 an oz. To think I had my boy using lead fishing weights or steel washers...
Actually for that last race we didn't use tungsten (Everywhere was out of it
) and we ended up using 300grain .44 magnum bullets that were lead with a copper jacket. Just the bullet, which I had a bunch of for reloading, not the whole cartridge case. This link kind of explains it...
http://www.pinewoodpro.com/weight-sets.htm
Feb 9th 2010, 3:03 am
#17
Forum Regular
Joined: Apr 2005
Posts: 168
Re: Pinewood Derby ??
When we did pinewood derby just after we moved here there was a similar father in the pack. He worked at CU Boulder as an astronomer.
Come time to build the cars he created a mathematical model to determine the best weight placement, then HE built the car. After carefully shaping the block and aeorodynamic styling etc, he had drilled out a chamber at the back of the car and filled it with molten lead. (no little lead weights glued to the bottom of the car for him
Come derby day he did however let his son place his car on the track. My son was 8 at the time, all the work on the car was his - it looked like a cheese wedge but he was proud of it. He made it to he final with the astronomer - there were some worried looks on faces but in the end the astronomers car won - but it really was only by a whisker.
All the kids knew the score - they wern't blind - most of the congratulations amongst the kids went to my son - he was as pleased as punch.
Come time to build the cars he created a mathematical model to determine the best weight placement, then HE built the car. After carefully shaping the block and aeorodynamic styling etc, he had drilled out a chamber at the back of the car and filled it with molten lead. (no little lead weights glued to the bottom of the car for him
Come derby day he did however let his son place his car on the track. My son was 8 at the time, all the work on the car was his - it looked like a cheese wedge but he was proud of it. He made it to he final with the astronomer - there were some worried looks on faces but in the end the astronomers car won - but it really was only by a whisker.
All the kids knew the score - they wern't blind - most of the congratulations amongst the kids went to my son - he was as pleased as punch.
Feb 9th 2010, 5:35 am
#18
Unmitigated Gall
Joined: Dec 2006
Location: it's still too dark to tell
Posts: 16,162
Re: Pinewood Derby ??
It's not pretty... but like I told my son, "Pretty" doesn't win races Boy!!!
Feb 9th 2010, 5:43 am
#19
Lost in BE Cyberspace
Joined: Feb 2009
Location: North Charleston,SC. born in Stockport,UK.
Posts: 10,109
Feb 9th 2010, 8:05 am
#21
Unmitigated Gall
Joined: Dec 2006
Location: it's still too dark to tell
Posts: 16,162
