Aero design question - Page 3 - Fuel Economy, Hypermiling, EcoModding News and Forum

rkcarguy · 04-07-2009, 06:06 PM

Quote:

Originally Posted by theunchosen

Using sprayed in FG could be. . .risky. I've had FG cary body parts explode on the highway from rocks. It makes a lovely mess.

If you wanna go FG all you need to do is get a mold fabbed, put a liner down, lay Fiberglass cloth(Fiberglass Cloth in bidirectional weave) coat in resin and fixative and sit and wait. It heats up a little you wait 45 minutes pop it out sand, smooth paint bolt.

My first boss used to own a small company that made composite aircraft parts and small boats. They would coat the prototype with a waxy non-stick stuff, then lay a fiberglass mold over it and build up many layers. After it dried they would remove it, beef it up with a wood structure, and do some finish work such that the items done in the mold came out needing minimal handwork. I have never done this work myself but I understand it and know how it works. Fiberglass stinks and I have no desire to work with it myself unless I had a totally ventilated filtered room to work in wearing a haz-mat suit( I have neither). My machinist/fabricator work already cost me my lower back(reason I am at a desk now), and I'd like to retain a healthy respiratory system.

theunchosen · 04-07-2009, 06:40 PM

Ah, yes you could layer it. . .I forgot you said it was a bathtub. . .manufacturer? The woven cloth is not as bad as the spray by a long shot. I made a duplicate of my current front bumper in case it exploded too.

Although the current bumper is easily 2-3 times stronger. The weave gives the material MUCH more strength than spray but it takes more time than spraying it and heating. With most resins out there you don't have to heat it or vacuum pump, but if you want you can get pre-impregnated for the ultimate in strength-density.

rkcarguy · 04-07-2009, 08:00 PM

^^ Or use carbon fiber cloth instead...but I'd like to drive this thing not sit and drool on it all the time and get pissed everytime I get a rock ding.
Hoping to have Autocad in the mail today when I get home....

theunchosen · 04-07-2009, 09:51 PM

Quote:

Originally Posted by rkcarguy

^^ Or use carbon fiber cloth instead...but I'd like to drive this thing not sit and drool on it all the time and get pissed everytime I get a rock ding.
Hoping to have Autocad in the mail today when I get home....

only downside is CF is way more expensive. . .and its actually heavier. If you wanted to do the chassis CF is the way to go but for body FG I would recommend some form of very resilient paint lol. FG is as light as it comes and since body panels don't support weight. . .

Yeah. . .rocks are the bane of composites. . .or at least CF and FG. I'm still looking for something thats a much thicker paint that might be able to dissipate rock impact energy. . .

rkcarguy · 04-08-2009, 12:17 AM

Quote:

Originally Posted by theunchosen

only downside is CF is way more expensive. . .and its actually heavier. If you wanted to do the chassis CF is the way to go but for body FG I would recommend some form of very resilient paint lol. FG is as light as it comes and since body panels don't support weight. . .

Yeah. . .rocks are the bane of composites. . .or at least CF and FG. I'm still looking for something thats a much thicker paint that might be able to dissipate rock impact energy. . .

Vacuum formed tupperware body panels=Win

theunchosen · 04-08-2009, 12:22 AM

laugh laugh laugh FTW!

evolutionmovement · 04-08-2009, 05:51 PM

Rubberized undercoating could absorb some minor impact damage to composites. Wouldn't look so nice and would be heavy, but would probably work.

rkcarguy · 04-10-2009, 12:29 PM

Autocad came wednesday and drawings are in progress. It's funny because so far it looks similar to a flatter 1st gen MR2...
I'm talking to a friend of mine who seems to think I'm not too far off taking a mold off of the original nose fabrication and using it to vacuum form ABS or Polycarbonate sheet....
I really like the K-1attacks nose and have styled mine similar however more neutral shaped as far as aero and no batmobile vents holes and stuff.
Getting headlights at 24" on center from the ground is proving to be the hardest part, because the whole thing is only 28" off the ground to the bottom of the glass....
I'm thinking I need some really wide thin headlights lol...

winkosmosis · 04-10-2009, 02:20 PM

Try putting the headlights in pods, mounted on aerodynamic stalks. I think that would minimize the disturbance to the flow over the vehicle itself.

It's actually practical because the vehicle can use off the shelf projector headlights like these

Low beam http://www.rallylights.com/detail.aspx?ID=1800

High beam http://www.rallylights.com/detail.aspx?ID=1801