Your friendly neighborhood Laserman

Secrets, tips, tools, design considerations, materials, the "science" behind it all, and other topics related to building the cars and semi-trucks.
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whodathunkit
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Re: Your friendly neighborhood Laserman

Post by whodathunkit »

Joe,
Thanks for the Tungsten Puma Weights!
The weight's showed up in the mail today at Hi Noon.

But I want you to see this.
Image
Image
No Apologies needed over your packaging Joe.
Just wanted to show you how the mail runs around here with a little bump and grind racing.
It's a good thing you taped them in. :whew:

And do you remember that brass hub cap?
Be looking for it in the mail now that i have your address.

Whoda.
What type of automobile can be spelled the same forwards & backwards?
Laserman
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Re: Your friendly neighborhood Laserman

Post by Laserman »

Hi Sporty,

The fellas over at the NPWDRL (adult racing league) are blazing fast.

It is all about the wheel/ axle prep, and I have no patience for it.

I raced a car about 6 months ago and to say I did minimal wheel /axle prep would be an extreme understatement.

The times my car put up (compared to the other guys) reflected that fact.
Laserman
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Re: Your friendly neighborhood Laserman

Post by Laserman »

Hi Mark,

I was hoping that you would not display what a "Sanford and Son" operation I am running here, but now that the cat it out of the bag...
If I read correctly the USPS will deliver an envelope the is 1/4" or less, that weighs 13oz or less.
That would probably be a solid chunk of lead no?
Perhaps Stan (or someone with a mind for it could figure it out)
Tungsten is about 18g/cm
I think lead comes in at 11g/cm
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sporty
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Re: Your friendly neighborhood Laserman

Post by sporty »

Joe, check your email
ngyoung
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Re: Your friendly neighborhood Laserman

Post by ngyoung »

Pretty much everything that I have learned is on the forum that is associated with the NPWDRL. I started sending in proxy a car at the beginning of the year using completely BSA stock parts. I did the work prepping the axles and wheels using locally found supplies that I could justify using around the house for other none pinewood derby use.

For axle prep it wasn't much different than what is told here. I found a pack of fine grit sand paper at Hobby Lobby that goes from 400-14000. After filing the burs and tapering the axle head I went through the progression of sandpaper grits. I finished the axles off using Brasso metal polish I found at Home Depot and a scrap piece of leather.

For wheel prep I found Novus 2 plastic polish and a car paint polish/protecter called Liquid Glass. I used the Qtip stalk in a hand drill method to polish with the Novus then applied the LG like car wax. After that dried I buffed it out.

The 2 things that I did buy from a derby vendor to start were the Silver Bullet and the oil. I can't find jig in my area so I used Dupont chain saver on the axles before applying oil and installing the wheels.

Doing all the with stock parts yielded a 3.04 time in the BASX class which is no fenders and a wheel weight minimum of 2.4g. After getting grooved .092 steel axles and lathed wheels with the double step removed my time went to 3.02. I have since gotten some Red Rocket to replace the LG and started using delrin washers, the same wheels on new bodies I have gotten my times down to 2.99 with a best run of 2.987. The top guys that have been doing this for years are getting run in the low 2.97.

My next step I think I am keeping everything the same and only adjusting the COM to get more consistent runs. It was shaking bad in the last race. I had 2 rows of 6 in the back and 2 more rows right in front with some putty the fill in the rest. My COM was under 1/2". I should have moved it forward but I wanted to see how it ran as i and adjust from there since it was a new car body.

I am not a top racer and I am still learning new things a little at a time. Most of what I have applied and shared with others has come from the guys that have won or are running neck and neck with the winners, some of whom post on here as well.
Laserman
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Re: Your friendly neighborhood Laserman

Post by Laserman »

Laserman wrote:So I wanted to tighten up the gaps around the wheels with the last layer of wood.

At the same time I started to consider where I should put the remaining 1.5 oz

In the adult racing leagues it is en vogue to "bias" the weight towards the DFW side.

An idea is forming in my head

Image

Image

This thing is approaching bird skeleton qualities. (Always a plus)

I would really like to reinforce the skirt a bit with more plywood and get rid of the "body" between the front and rears altogether.

I am kind of getting attached to this design though and I am scared to push it too far.

It might be time to "man up"

Image
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whodathunkit
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Re: Your friendly neighborhood Laserman

Post by whodathunkit »

Joe it's look'n good!
What type of automobile can be spelled the same forwards & backwards?
Laserman
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Re: Your friendly neighborhood Laserman

Post by Laserman »

Image

Thanks Mark!

So I left a little space inside the rear fender area, because I figured I could fit some weight down there.

The more I learn about the PWD, the more I learn that it is a weight game.

Where ya want it, and where ya don't.

Image

Beyond that it's mainly semantics
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Re: Your friendly neighborhood Laserman

Post by Laserman »

Image

Well...

Here she is

From here in NYC she will be heading over to BR/ Maglev's neck of the woods in MO.

With their expertise I have a feeling that this half baked theory could become fully baked!

I managed to get quite a bit of weight really low on the rear fender area.

It occurred to me that even if the weight is in front of the rear axle, then by putting it lower on the car, one is getting it a little higher on the hill. Right?

Image
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sporty
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Re: Your friendly neighborhood Laserman

Post by sporty »

Well, either way. Its neat and I'm sure its been fun tinkering with it. :cry:
Sporty
ngyoung
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Re: Your friendly neighborhood Laserman

Post by ngyoung »

Whoa there LM. You just going to drop that pic with the weights on us and not talk about how you implemented a wheel weight inside a reversed wheel? You attach it permanently to the axle head?
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Re: Your friendly neighborhood Laserman

Post by DerbyAddicted »

Laserman wrote:Image

Well...

Here she is

From here in NYC she will be heading over to BR/ Maglev's neck of the woods in MO.

With their expertise I have a feeling that this half baked theory could become fully baked!

I managed to get quite a bit of weight really low on the rear fender area.

It occurred to me that even if the weight is in front of the rear axle, then by putting it lower on the car, one is getting it a little higher on the hill. Right?

Image

LOVE that car. Looks amazing! Damn, I may need to buy a laser set up. How expensive could it be?? Not too steep of a learning curve, is it? ;)
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whodathunkit
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Re: Your friendly neighborhood Laserman

Post by whodathunkit »

HI Joe,
Your weight is looking good and coming along nice for the reversed wheels.

Are you useing the max-v 0.65oz tungsten mini cylinders
and is that an older style wheel hub for the weight holder?

You have some of the craziest Ideas..

Whoda.
What type of automobile can be spelled the same forwards & backwards?
Laserman
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Re: Your friendly neighborhood Laserman

Post by Laserman »

Image

Here is another way to get some weight into the void in the rears when they are run reverse.

I think they look better this way with the Puma Racing Weights, but Bracketracer and Maglev will have to run the tests to see which setup the car likes.

Image
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Vitamin K
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Re: Your friendly neighborhood Laserman

Post by Vitamin K »

Man, these cars look like they're made of bone, vat grown in some secret genetics experiment laboratory. Sick, in the best sense of the word. :thumbup:

I'd love to see a time-lapse video of your build process, if you ever felt so inclined, Laserman.
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