Full Weight On Derby Car
Full 5 Ounces for Optimum Performance
This is a very common mistake made by first time derby car builders. A derby car relies on gravity to make it move down the track, the more weight you have, up to a certain point, the faster and farther, your car will travel. 5 ounces total weight with wood, wheels, axles and added weight is optimal and usually the rule for most races. Your car will be weighed by the check-in crew at your race. Their scale may be different from yours so be prepared to make adjustments when you get to the event. Make sure you arrive early enough to make any adjustments needed.
The best type of material for weight
You may think that anything that you can attach to your car will be sufficient in bringing it up to full weight. This is not true. Many people will improvise and use coins, solder, metal and even action figures, but these are not the best way to add weight to your car. You want weight that is very dense (small but heavy - packed tightly together) so you can keep the weight in the area that will give your car the best performance.
Lead is one of the best and cheapest types of material to use for your car. Many people say not to use lead and I do caution it is poisenous, but only if you don't handle it correctly. When handling lead do not touch your mouth, don't handle it around food items and make sure you wash your hands after handling. I am not an expert on the safety of lead so make sure you check this out thoroughly before using it. I will say that I have used lead for most of our derby cars.
Lead is very dense and can be molded and shaped into several ways to fit into your car. You can use lead car weights, fishing sinkers or do like I do and purchase it online in a 3/8 rod which is easy to install into the car after drilling. You can use a hammer to shape it the way you want, if possible. I use the 3/8 rod so I can drill into the wood block using a 25/64 brad point drill bit and slide the weight into the body. This gives your car a sleek look as you don't see any added weight outside the body.
Lead weight works for several applications, especially a wedge car.
Tungsten steel is one of the most dense materials you can use for your derby car. I think it has been said that gold is denser, but I don't think you want to put that in your $3.75 derby car. Tungsten steel is close to 5 times more expensive than lead, but it is much more compact for the amount of weight. You would usually want to use tungsten steel when you are making a very low profile and or extended wheel base car. You can put more weight in a much smaller area with tungsten but this is only an advantage if you need the smaller portions to get your center of gravity correct. Many car builders are using this material more and more as it gets very competitive.
You can use just about anything to bring your car up to 5 ounces but if you want the best performance you need to use either Lead or Tungsten Steel so you will be able to have the right amount of weight in the proper places. If you are a first time builder, lead is probably your best bet for the price and to experimentation.