Questions

[46u]

I did a search and came up with way too many pages to go through with my poor eyes so if some one could answer or point me in the right direction I would greatly appreciate it.

I have read on the COG some say 1/2 some say 3/4 and other say 1 inch. What normally is best for a car with all 4 wheels touching the track and what is the difference where you put the COG in this range?

One a car with 4 wheels touching is it better to make it run straight or make it a rail runner?

I have less the 2 days to get this car down and I was only able to start yesterday. The rest of the stuff is suppose to get here today.
Thanks Much
Jeff

[FatSebastian]

What normally is best for a car with all 4 wheels touching the track and what is the difference where you put the COG in this range?

It may be helpful to know what type of track you will be racing (wood v. aluminum, Besttrack's tight curve v. the large curve of Piantedosi's catenary-sag, etc.) to make a determination of what is best.

One a car with 4 wheels touching is it better to make it run straight or make it a rail runner? I have less the 2 days to get this car down and I was only able to start yesterday.

Because of your time constraint, I'd suggest you either email or PM Sporty, who is IMO the resident authority on 4-wheels touching.

[sporty]

Oh boy, thats a pretty tight time frame.

I do a four on the ground rail rider, but really cant teach you that in that amount of time. is this exstended or standard wheel base ?

I do not even know, if I would recommend trying to rail ride with so little of time before the race. How good of a builder are you ? what tools you got and how much time you got ? I mean working on the car time ?

10 hours ? this does not include paint time !

I am the kind of person that can give you advise, but my advise is only as good as your comprehension and builder skills.

Including that there are several areas to focus on.

[46u]

I did not find out from my daughter that my grandson 7 and I would have to build one till last Friday. Since there are not any hobby shops with in 100 miles of me that carry pinewood derby items I had to order them. Last order I am hopping to be here today. Car has to be ready for this Saturday.

Since I have spent MANY hours online reading and trying to learn. I have been trying to get my daughter to find out about the track to no avail. She has two sets of twins both under the age of 2 and my grandson which I am helping with the pinewood derby car so you can understand how she spends most of her time.

As far as pinewood derby cars I am new to. But I have been racing RC buggies for about 15 years and have a small engine machine shop in my basement. I have been riding and working on motorcycles none stop for over 40 years.

So you see my predicament. I have some of the special tools for building a pinewood derby car and hope one day to have them all as it looks like I have at least my other 3 grandsons to help in the feature and more then likely my granddaughter will want one as well.

I am a tool freak and even when working on motorcycles and my RC buggies I beleive in the right tool for the job. I am hopping before it is all over I will have all the special tools and even a 32 foot test track with a timing system but right now I just need to have one car ready for this weekend so I do not disappoint my grandson but would like it to be competitive.
Thanks all for doing all you can to help me.
Jeff

[sporty]

Then if you can watch my axle whole drilling tip videos. before you start. they first and most important part is good axle whole drilling and you may have those tools or something close to it. To get you started.

Then you go from there to axle work and wheel work. and then from there to deciding on RR to strait runner. and weight placement.

[FatSebastian]

Then if you can watch my axle whole drilling tip videos

...which I think is a reference to this post.

[46u]

We have to use a Cub scout slotted block. Only tools I have or coming are the derby worz axle installer, Pine car hub tool, Pine car axle straightener. All so have the derby worz hub saver tool which I found out will not work with the Pine car hub tool. I all so have a axle polishing kit and a set of turned wheels that should be here today.

I guess for now I will make it run straight and set the COG at 3/4 inf front of the rear axle. I have more then enough weights. We will start working on his car for 2013 a WHOLE lot earlier and should have more of the special tools.
Thanks for the input.
Jeff

[46u]

I did check the slots in the block with a square and they are square.

[sporty]

thats good that they are square, but the hard part is keep those axles true, when trying to put them in those slots. thats where one side of the wood is either softer or gives more and causes the axle not to be true and strait. something to keep a eye out for.
Sporty

[46u]

Thanks all! I understand this year is going to be mostly a learning experience. Mail lady just run so it is time for us to get back to work and do as well as we can. Will keep all posted how it turns out. I am going to take my video and still camera to the race.
Thanks again
Jeff

[46u]

I know nothing like most others here have but this is what we go up in the past 5 days. I all so have tools like Dremel, sanding tools, drill press and so one. Still have a lot to get. I all so have to show off my second set of grandchildren twins that are less then two weeks old. Children are great but grandchildren are even better!!!!!!!!!!!!

[Stan Pope]

Wow! There's a lot of PWD building fun awaiting you there! And you have time to learn a lot more before they are ready.

[sporty]

Awwww.


Thank You for sharing !


Sporty

[46u]

OK after about 8 hours LOL I have the axles, wheels and COG done. I went from my cheap postal scales to my triple beam. I wish the COG was a little more towards the back to meet the deadline it will have to run like it is. I had to route out on the front to just get it were it is now. I will never build another one where the back curves in at the bottom. Learning a lot!
Thanks All!
Jeff

[sporty]

that design is allot of wood. more wood. the less weight and the less weight, also means harder to get the cog where you want it. That design means you have to route out allot of wood to be able to add in 3 to 4oz of weight and get it where you want it.

It reminds me of my sons first car.


here, we did the back end close like that too. in a way. My grandpa cut thus shape out. we bought those decal, which they may even still sell for the pwd cars.





It never won a race, We were slow back then too !

Sporty