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Why is plastic more pts than aluminum?


Ogren-Engineering
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Really, the sheet plastic is 3pt per sq. and the sheet alloy is 2pts.     Why not more inline with actual cost?? 

 The roll of plastic is about 1$ per sq. ; http://www.ebay.com/itm/Speedway-25-ft-Roll-Airdam-Body-Extension-Plastic-White-1-8-Thick-/131500510352?hash=item1e9e0a8c90:g:U~wAAOSw3ydVu7wO&vxp=mtr

 

 The sheet aluminum is at least 4$ per sq; https://www.metalsdepot.com/catalog_cart_view.php?msg=

 How do we get this fixed??  Is this simply an oversite?  Thanks,MM 

Edited by flyinglizard
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It dates back to the Lexan wars of 2014. None of these really make any sense any more, seems like any car with front end aerodynamics = splitter and 10 points and any car with rear aerodynamics = wing and 10 points. Who really cares about anything else?

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8 minutes ago, mhr650 said:

It dates back to the Lexan wars of 2014. None of these really make any sense any more, seems like any car with front end aerodynamics = splitter and 10 points and any car with rear aerodynamics = wing and 10 points. Who really cares about anything else?

 

 

"The Lexan War of 2014"  :o lol

 

Don't forget "The brake pad wars of 2014" either.

 

I remember impound being:

Team A -  "I am protesting your glass windows"
Team B - "Oh yea? I am protesting your brake pads"

Team C - "Rabble rabble rabble........cardboard windows".......rabble 

 

 

 

 

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44 minutes ago, TiredBirds said:

4x8 sheet of 1/8 scratch resistant lexan (something you could use for a front or rear window) $380 (or more) $11.87 sq foot. You can't really use .060 for much.

 

And a 4x8 sheet of 1/8 aircraft quality MIL-P-6070 plywood is $140, $4.38/sq ft.  High-end plywood is ~1/3rd the price of high-end plastic.  Yay proportions!

 

While we're on the topic, does Jabroc count as wood?  :ph34r:

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2 hours ago, TiredBirds said:

4x8 sheet of 1/8 scratch resistant lexan (something you could use for a front or rear window) $380 (or more) $11.87 sq foot. You can't really use .060 for much.

Sure you can.

 

This is Polyethelene in .11 thickness.

http://www.speedwaymotors.com/Colored-Plastic-Rolls-10-Ft,1557.html

 

This is polystyrene in .060 (BTW, .080 or .125 are only marginally more expensive).

http://www.ebay.com/itm/YELLOW-STYRENE-POLYSTYRENE-PLASTIC-SHEET-060-THICK-24-X-24-/331023362230

 

I chose .060 specifically.  Its the right thickness and strength to make splitter parts, side skirts, etc.  

 

Also, Lexan is free for windows, hatches, etc (as it should be, its a safety matter.  Opaque window coverings even being allowed, much less encouraged by the rules, were monumentally stupid)

 

 

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41 minutes ago, Huggy said:

Also, Lexan is free for windows, hatches, etc (as it should be, its a safety matter.  Opaque window coverings even being allowed, much less encouraged by the rules, were monumentally stupid)

Agreed. IMO the stupid part was tech not having the testicular fortitude to tell these teams who showed up with cardboard and tarp window coverings: "hey, you knew what the intent of the rule was and you're weaseling around the specific wording. Here's your 'fix by next event' ticket, next race we will charge you full lexan points on your cardboard". /rant

Edited by enginerd
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55 minutes ago, Huggy said:

Also, Lexan is free for windows, hatches, etc (as it should be, its a safety matter.  Opaque window coverings even being allowed, much less encouraged by the rules, were monumentally stupid)

 

They look really good though. This was our car during the 2014 Lexan war. 

 

1tcfe2PFtCInmJSWgrm7P3HBj_qVbO4SpJRS33eF

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3 hours ago, TiredBirds said:

4x8 sheet of 1/8 scratch resistant lexan (something you could use for a front or rear window) $380 (or more) $11.87 sq foot. You can't really use .060 for much.

has the price gone up alot?

Last time i bought a 4x8x3/16" sheet of scratch resistent poly carbonate (lexan), it was about $105 CAD.

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9 minutes ago, swrving said:

has the price gone up alot?

Last time i bought a 4x8x3/16" sheet of scratch resistent poly carbonate (lexan), it was about $105 CAD.

?? I just called a few places to get a quote. ebay has some in 1/8"x2x4' for 140 plus shipping but we need about 60x40

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What are tarps made out of?

 

 

Oh yeah....

"Made of woven polyethylene, tarps are weather and tear resistant, UV lamination, heat-sealed sea...."

 

" Polyethylene or polyethene is the most common plastic."

 

 

That whole thing was a complete and total Tech FAIL.   Any team running 'tarps' over window openings should have been charged the 3 points/sq ft for plastic.

Edited by NigelStu
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Anyway...  Fiberglass and Fiber-Reinforced Plastic fall under 'plastic', which seems to be a valid/reasonable point gain at 3 / sq ft (much easier to shape/mold something fiberglass than wood, and can provide good strength/rigidity).

 

Seems to me that the point structure should change.  

 

I would like to see:

Wood/plastic/metal sheet - 2 pt / sq foot

fiberglass/FRP - 3 pt / sq foot

Metal tubing - 5 pt / linear foot

3D plastic/FRP/Metal printed stuff - 5 pts / ?? (lb?)

Carbon fiber / Kevlar - 10 pt / sq foot.

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1 hour ago, NigelStu said:

What are tarps made out of?

 

 

Oh yeah....

"Made of woven polyethylene, tarps are weather and tear resistant, UV lamination, heat-sealed sea...."

 

" Polyethylene or polyethene is the most common plastic."

 

 

That whole thing was a complete and total Tech FAIL.   Any team running 'tarps' over window openings should have been charged the 3 points/sq ft for plastic.

Quite right. Although intent and enforcement of the rule was for lexan, the specific wording in the rulebook said "plastic".

 

And going back to my previous point, the intent of the rule was to assign a point value to the perceived improvement in aerodynamics. Therefore, ANY material accomplishing the same end result as a lexan window should have been valued the same. 

 

That was a tech fail.

 

@red0 I was absolutely aware of that. Also aware of you guys using sheet metal on the sides because it was less points than lexan.

I blame Condren. 

Edited by enginerd
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2 hours ago, NigelStu said:

What are tarps made out of?

 

Oh yeah....

"Made of woven polyethylene, tarps are weather and tear resistant, UV lamination, heat-sealed sea...."

 

" Polyethylene or polyethene is the most common plastic."

 

That whole thing was a complete and total Tech FAIL.   Any team running 'tarps' over window openings should have been charged the 3 points/sq ft for plastic.

 

We started running our cars in WRL after 2014, but if we continued we planned to use stretched animal hide in place of the tarp so that way it would not be "plastic".

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