Every so often I see a post from a new PWD enthusiast asking for step-by-step instructions for building a car so I thought I'd document the process I just went through to build an Outlaw car.
But, let me preface this post by saying that it's a culmination of everything I learned from Stan Pope's on-line manual and from this forum. None of the concepts or construction steps are original ideas that I came up with.
So, here goes:
First, I doodled an design during a boring meeting at work. I then used Excel to make a 7" X 1 3/4" grid paper that helped me accurately make a template. Here's the design I chose:
You can see that I went with a very thin design. I drilled axle holes using a floor drill press and I placed them as high as possible while still maintaining 3/8" clearance under the car. I'm using 1/4" tungsten cubes for weight and this allowed almost all the weight the be level or under the plane of the axles. You can see that I used a scroll saw to cut the shape and that I removed a lot of wood. The final wood weight was about .3 ounces. I know that some builders go for < .2 ounces but I chose to not go that light.
Next, I calculated the weight. I planned to used 4 rows with 6 cubes in each row. I row of 6 cubes weighs 1 ounce. I had to also throw in a .3 ounce lead weight to get to 5 ounces. Here's a pic of the weight. You can also see that I'm using razor wheels premounted on bearings that I bought from MaxV. The total weight not including the epoxy I'll be using plus paint was 4.9 ounces. That was a mistake because after I poured in the epoxy the total weight came to 5.15 ounces and I then had to drill out a little of the lead. No big deal, though. Note that I use a scale from Harbor Freight. I think you can get them on-line for $9.95.
I then got the car ready for pouring the epoxy. I use 5 minute, 2 part epoxy from Devcon:
Here's a pic of the car ready for epoxy. Note that I place it on wax paper and that I tape a small piece of wood on the back to contain the epoxy. That tape also keeps the epoxy from getting in the axle holes.
And here is the car 15 minutes later. Note that the epoxy dries clear and very smooth. The stuff is fantastic to work with.
Even though the directions on the epoxy says it is totally dry after a short time, I let it sit at least a full day to make sure it's fully cured. Then, I use my bench mounted belt sander to sand the small piece of wood off the back of the car and to sand down the top. This took about 1 or 2 minutes. Epoxy is very easy to work with. Note that I placed the car on one of the pieces of grid paper I made using Excel. You can see I laid out the grids so that when I hand drew the design I made sure it was accurately balanced. This is a rail rider and I removed 3/32" of wood from the front right wheel.
And then I was ready for priming and painting. I like to use round toothpicks in the axle holes and then balance it on little blocks. This keeps paint from getting in the holes. The weather here in WI has been around - 25 to - 35 with wind chills so I had to paint inside this year. However, I used a paint mask and fans to deal with the fumes.
I like the Dupli-Color primer/paints and used this combo:
Both dry in about 10 minutes. The high build primer is very forgiving and does a great job of filling imperfections.
And here's the final result. The COM is exactly 5/8" in front of the rear axle. I ran a few tests on a 32' Piandosi 3-lane track and ran sub 2.3's. My son's Pack and District winner runs 2.35's. I was expecting the Outlaw to be a bit faster than it is but I'm still happy with it. Total construction time was less than 2 hours, and the work was done in 15 minute increments over 10 days. I hope you find this post useful.
I liiiiiike it!
No paint, just lacquer. We call her "Disclosure".
