Built the car Backwards

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knightp25
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Built the car Backwards

Post by knightp25 » Thu Jan 08, 2015 7:54 am

Just realized i built the car backwards, the shorter axle is in the front and the longer portion is in the rear.

Will this make a difference, and should i just buy a new car and start over again. any thoughts?



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Vitamin K
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Re: Built the car Backwards

Post by Vitamin K » Thu Jan 08, 2015 8:03 am

knightp25 wrote:Just realized i built the car backwards, the shorter axle is in the front and the longer portion is in the rear.

Will this make a difference, and should i just buy a new car and start over again. any thoughts?
It makes a difference, because the other way around lets you get your center-of-mass further back while maintaining better stability down the track.

Has the car already been weighted? How far are you along with construction?



knightp25
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Re: Built the car Backwards

Post by knightp25 » Thu Jan 08, 2015 8:11 am

i put weights in the car and have it painted, just have to polish the wheels and put them on



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Vitamin K
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Re: Built the car Backwards

Post by Vitamin K » Thu Jan 08, 2015 8:22 am

I hate to tell anybody to totally scrap a car, but I guess you have to decide what your priorities are. Without knowing what you've done for your build, it's hard to say how much of a difference the wheelbase placement is going to make for you. Are you and your scout(?) heavily focused on winning, or do you just want to have fun building and running a car?

You can still get speed gains with good alignment and polished axles and bores.
knightp25 wrote:i put weights in the car and have it painted, just have to polish the wheels and put them on



ngyoung
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Re: Built the car Backwards

Post by ngyoung » Thu Jan 08, 2015 9:15 am

Is the bottom still flat? You could still re-drill the axle holes if the body style will allow you to. Does your rules allow for extended wheel base? You may only need to move the back wheels farther back if they do. If they require using axle slots you just need to make a new slot by sawing up to your new holes to expose them. Can you provide a picture? What tools do you have at your disposal for drilling?

For moving the weight you can get light weight epoxy putty from a hobby shop to fill the old weight pockets. I guess it also depends on what type of weighting you did. Plates or cubes in the bottom? Holes drilled in for cylinder rounds? If you can post a pic of the bottom we may be able to better help you as well.



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Noskills
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Re: Built the car Backwards

Post by Noskills » Fri Jan 09, 2015 3:49 pm

I'm with ngyoung. The front wheels are now in the perfect spot. Move your read axel to 5/8 in the end and you are in good shape.
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Stan Pope
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Re: Built the car Backwards

Post by Stan Pope » Fri Jan 09, 2015 8:00 pm

I'm in favor of preserving the Cub's effort if at all possible (without sacrificing performance). So, I'd try to make the car he has built work.

Do your rules allow drilled axle holes? Do your rules allow wheelbase other than original slots?

Recover by:
Moving weight and
1. Sawing fresh axle slots in the right position, or
2. Drilling axle holes in the right position, or
3. Drilling axle holes at 5/8" from rear,
according to rules limitations.


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Rfieldbuilds
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Re: Built the car Backwards

Post by Rfieldbuilds » Sat Jan 17, 2015 12:55 am

Ok. I hate to admit it. But yes, I've been there before. My son took first place in OUR derby... I make mistakes in coaching my son every year.
In the end, each tip you employ will add speed. Depending on your competition, these will either add up to help you towards a first place finish or a second place finish, or something else in Packs with tight competition. In PWD, effort=reward.
Always "Do Your Best" as a coach and mentor, your efforts will be rewarded.
Regarding your present situation, consider your Pack, the reward for your son in his efforts, and is he willing or not to rebuild?

Edit-
To be honest, we have built two cars this season and realized we made mistakes. We (I) am hoping he will build another car tomorrow at our Council workshop which I host.

Keep at it and realize that an inventor fails 99% of the time and is successful maybe only 1% of the time. This is what has made America GREAT!



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