2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

umm plexi glass under the hood?

Thread Tools
 
Search this Thread
 
Old 05-20-03, 08:19 PM
  #1  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
umm plexi glass under the hood?

what temp do you think under hood this whould be subjected to?

I have loads of plexi glass, im thinking of making a cold air box... it seems that plexi would be a good way to keep heat out of the box... but im not sure at what temp the plexi will become soft. maybe more important at what temp does it start to break down and release fumes/gas.
It would be a bad *** looking cold air box.. but if its not gonna last but one summer day then it may not be worth the trouble.

so here is the question...

plexi glass or not to plexi glass.

Remember now i have it. so it would be free.

jaared
Old 05-20-03, 08:20 PM
  #2  
sold--no longer in debt

 
cloead's Avatar
 
Join Date: Dec 2002
Location: Cleveland, Ohio
Posts: 1,659
Received 11 Likes on 3 Posts
I would think plexiglass would melt pretty fast.. but I don't know for sure.
Old 05-20-03, 08:24 PM
  #3  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
guess ill have to do the oven test...
Old 05-20-03, 08:34 PM
  #4  
sold--no longer in debt

 
cloead's Avatar
 
Join Date: Dec 2002
Location: Cleveland, Ohio
Posts: 1,659
Received 11 Likes on 3 Posts
Lol I guess... be sure to set it on like... I don't know in an old pan or something so it doesn't drip everywhere.
Old 05-20-03, 08:41 PM
  #5  
Former Moderator. RIP Icemark.
 
Icemark's Avatar
 
Join Date: Apr 2001
Location: Rohnert Park CA
Posts: 25,896
Likes: 0
Received 19 Likes on 19 Posts
plexi should be fine, but it is very heavy when compaired to alum sheet
Old 05-20-03, 08:51 PM
  #6  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
not the plexi iv got... its 1/8 inch..

im doing the "oven test" now

ill post the results in a few more min

jaared
Old 05-20-03, 08:52 PM
  #7  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
how hot will it get in there?
Old 05-20-03, 08:57 PM
  #8  
Ho's and Cadillac Doors

 
2ndGen.rocket's Avatar
 
Join Date: Apr 2002
Location: ATL, GA
Posts: 2,703
Likes: 0
Received 1 Like on 1 Post
i made one out of plexi. It was actually Rhino Glass that I nabbed from the factory I worked at for the summer. It didn't come close to melting or getting soft, however it is a BITCH to work with. Cutting it sucked, drilling it sucked, getting it to fit sucked.
Old 05-20-03, 08:58 PM
  #9  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
umm how hot?
Old 05-20-03, 09:04 PM
  #10  
Rotary Freak

 
Join Date: Apr 2002
Location: Boulder, CO
Posts: 1,739
Likes: 0
Received 0 Likes on 0 Posts
maybe 200* F? more for a turbo car maybe.
Old 05-20-03, 09:09 PM
  #11  
Ho's and Cadillac Doors

 
2ndGen.rocket's Avatar
 
Join Date: Apr 2002
Location: ATL, GA
Posts: 2,703
Likes: 0
Received 1 Like on 1 Post
I had a Mechanical Temp gauge that was sitting just under my hood for a while, it never went over 150F in my N/A
Old 05-20-03, 09:26 PM
  #12  
SOLD THE RX-7!

 
Scott 89t2's Avatar
 
Join Date: Mar 2001
Location: Vancouver, BC, Canada
Posts: 7,451
Likes: 0
Received 0 Likes on 0 Posts
lexan would be much better if you want something clear
Old 05-20-03, 09:33 PM
  #13  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
HA! ok new idea...

umm ok so the oven test proved to me that i need to save the plexi for something more useful.

ok here is the result of a single layer @ 200 degrees. i set the timer for 10 min.. but i took it out after 6 min.


-------------------------------------------------------

ok here is the doubble layer with support @ 200 degrees.. it lasted fine for the 10 min! (just a lil' soft)


---------------------------------------------------------

so I upped the temp to 300 and had to take it out after about 5 min. (started to smell and turned white)


--------------------------------------------------------


Now it didnt melt and go to **** at 200... but it hazed.. then at 300 it turned white and was very soft once i took it out.... it stayed bendable for a good 10 min after it was out!

So ill use some metal, well it was worth a try!


jaared
Old 05-20-03, 10:13 PM
  #14  
on the road to insanity

iTrader: (7)
 
seveninphilly's Avatar
 
Join Date: Feb 2002
Location: Bristol, PA
Posts: 586
Received 0 Likes on 0 Posts
Re: HA! ok new idea...

Originally posted by Jaared
umm ok so the oven test proved to me that i need to save the plexi for something more useful.

ok here is the result of a single layer @ 200 degrees. i set the timer for 10 min.. but i took it out after 6 min.


-------------------------------------------------------

ok here is the doubble layer with support @ 200 degrees.. it lasted fine for the 10 min! (just a lil' soft)


---------------------------------------------------------

so I upped the temp to 300 and had to take it out after about 5 min. (started to smell and turned white)


--------------------------------------------------------


Now it didnt melt and go to **** at 200... but it hazed.. then at 300 it turned white and was very soft once i took it out.... it stayed bendable for a good 10 min after it was out!

So ill use some metal, well it was worth a try!


jaared
here is just a guess, but try that with a stock air box and see what happens....

I would guess it melts.

Anyone dare me?

I'll bet the plexi works fine
Old 05-20-03, 10:27 PM
  #15  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
i got enouf of this stuff to try makin one...

i guess it is worth a try... it sure would look nice clear and all...

im gonna keep the stock intake/scoop thingie over the fan shroud, and make a ram air thing from the F.T.P. hole too.

hella air is good!

jaared
Old 05-20-03, 10:46 PM
  #16  
Edmond Dantes

iTrader: (1)
 
Spraintz's Avatar
 
Join Date: Jun 2002
Location: Dallas, Texas
Posts: 1,930
Likes: 0
Received 0 Likes on 0 Posts
i knew a guy who tried to make a hood out of acrylic sign material with steel supports. it melted after 1 autocross run.

since "PLEXIGLAS" is juat a tradmarked name for clear acrylic then I am afraid it might melt.
Old 05-20-03, 11:15 PM
  #17  
on the road to insanity

iTrader: (7)
 
seveninphilly's Avatar
 
Join Date: Feb 2002
Location: Bristol, PA
Posts: 586
Received 0 Likes on 0 Posts
So I tried to follow your work

200 Degrees



here is the oven at 200 insert stock air box. 200 For 10 min not much it was warm smelled a bit, but felt strong for the most part

300 Degrees


A new game it was all soft. Not as bad as your plexi, but soft none the less

When was the last time you put your hand on the stock air box and it burned?

Draw your own con conculutions(sp?)

Last edited by seveninphilly; 05-20-03 at 11:19 PM.
Old 05-20-03, 11:29 PM
  #18  
Daily Domestic Killer

 
BlackRx7's Avatar
 
Join Date: Mar 2001
Location: San Antonio, Tx, USA
Posts: 2,425
Likes: 0
Received 0 Likes on 0 Posts
lexan is the ****, a friend of mine worked at a aircraft assembly plant (small time) he nabbed me like 20 sheets of 15x15 inch lexan and a few aircraft alumiun sheets
Old 05-20-03, 11:37 PM
  #19  
Senior Member

 
Kanaida's Avatar
 
Join Date: Jun 2001
Location: Columbus, Ohio
Posts: 270
Likes: 0
Received 0 Likes on 0 Posts
lexan hatch window.... mm... yummy..... hood made of all lexan... yummier.....


-Kanaida
Old 05-21-03, 12:48 AM
  #20  
Like Ghandi with a gun

 
Kenteth's Avatar
 
Join Date: Mar 2003
Location: Rapid City, SD
Posts: 4,584
Likes: 0
Received 0 Likes on 0 Posts
I think the air box should be alright. Unlike the rest of the engine which is heated by ambient air and rising heat from the engine, the airbox has a constant supply of new cool air from outside. The air is constantly moving through the box touching all the inside surface area to keep it cool. Just my two cents. I'd say it wouldn't reach above 175 unless using some massively thick plexi, in which case the moving air inside the box may not be enough to keep cool the outside of the plexi.

Remember in science class when you put the match under dixie cup filled with water and it wouldn't burn. Same theory, just distorted and shorted a great length since air is xx times less dense than water.
Old 05-21-03, 12:51 AM
  #21  
Like Ghandi with a gun

 
Kenteth's Avatar
 
Join Date: Mar 2003
Location: Rapid City, SD
Posts: 4,584
Likes: 0
Received 0 Likes on 0 Posts
a better question to ask is why does it take longer for cars to warm up in -10 degree weather. Its not because of the ambient air, its because of the moving air hitting the radiator.

This of course saying you have a stuck open thermostat or something illogical like that.

Moving air cools greatly, thats why we make air to air intercoolers.
Old 05-21-03, 01:26 AM
  #22  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
holy sheet man!!! you did it.. HA! stock airbox in tha oven...

well lookin that the result of that... im gonna make a airbox out of my "plexi".. its not the plexi brand.. when i went to buy the sheet, they had plexi and a better brand (more shatter resistant) so i upgraded to it...

Ill post pics of it in the different stages... im gonna work on the car all weekend. I hope i get it runnin too.. my starter went bad.

with all this talk im gonna heve to make it look good...

Does any body want me to save the measurements? maybe make a template? i guess i will just incase someone wants it later.

jaared
Old 05-21-03, 01:39 AM
  #23  
Kim
OBEY YOUR MAZDA

 
Kim's Avatar
 
Join Date: Oct 2002
Location: Denmark
Posts: 3,060
Likes: 0
Received 2 Likes on 2 Posts
Plexiglass(Acrylic) or Lexan(Polycarbonate) can be painted from the inside of the box that youre making and it looks really shiny from the outside.
Just look at a R/C racecar body which is lexan painted from the inside.
Kim
Old 05-21-03, 01:44 AM
  #24  
Ahhhhhhhh hhh....

Thread Starter
 
Jaared's Avatar
 
Join Date: May 2003
Location: www.wRongPeople.com
Posts: 837
Likes: 0
Received 0 Likes on 0 Posts
im gonna rock the clear.... thinkin of some custom ingraved something... ideas are flowing like crazy... man i WAS bored... but i found a cure.

jaared
Old 05-21-03, 01:55 AM
  #25  
Kim
OBEY YOUR MAZDA

 
Kim's Avatar
 
Join Date: Oct 2002
Location: Denmark
Posts: 3,060
Likes: 0
Received 2 Likes on 2 Posts
You got me thinking, I work with plastic injection moulding so at work we have alot of scrap lexan that could be used for an C.A.B.
Thanks




All times are GMT -5. The time now is 09:07 AM.