On Feb 9, 2:30 pm, "Jim" wrote:
Thank you to all of you who have provide tips on Pinewood Derby cars
in response to a previous post. We would like to ask a couple of
follow-up questions:


My answers are based on what me and my son did for his car (1st place
his Webelos division). YMMV, but it worked for us.

1. What is the best way to make sure that the axle slots are square to
the body of the car? We have the clear plastic tool sold at the Scout
shop that helps make the determination. However, we were not sure the
besy way to "straighten" the slots and then get the nails/axles to
follow the new line of the slot.


Depending on the rules you can do a couple of things. Last year we
didn't use the slots that were there but rather drilled holes in the
side with a drill press. This year, we did something a little
different. We filled in the slots with a filler and re-cut the slots
ourselves. We simply used a square and laid out the first axle.
Then, we very carefully measured that point ot the rear axle and laid
out and cut that axle.

2. We used the dry lube sold by the Scout shop. Everyone has been
mentioning using graphite. We are only allowed to use dry
lubrication, but we can use graphite. Is that what is typically sold
in the Scout shops? In other words, do we need to look specifically
for dry graphite lube or is all of the dry lube graphite anyway?


If it's sold by the scout shop you should be in good shape. One of
the things we did was to polish the snot out of the axles. An
additional step that someone recommended was to place your nail in a
drill press with the wheel on. Hold the wheel as the nail is spinning
and add lube to the axle while it's spinning. Apparently, that helps
to further polish out the axle and embed lube in the wheel and axle.
Seems to have worked for us.


3. How do you straighten the axles in order to make the car go
straight? When we tried to do this last year after the axles were on
the car, it seemed to be impossible to move them and have them stay in
place. Is there a good process for doing this? What are some steps
before and after the wheels are on the car?


Bruth force! Actually, if you lay it out carefully you will get a
fairly straight riding car. Any adjustments would be simply grabbing
the wheel and bend it by hand. It doesn't take much.

Just a couple other things that might make a difference. I've heard
that having 3 wheelers makes a difference. Check your rules on that
one. That is, one of your wheels simply doesn't touch the track. The
friction of three wheels is less than four. Also, on the wheels
themselves some people make the part of the wheel where the nail goes
through convex. Again, less friction. And last, again with the
wheels, people also sand back, at an angle, the portion of the wheel
that could touch the car.


Thanks again for your advice. We are looking forward to using all of
these tips when we build our next car.

Jim