Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now

Now available from EcoModder: ScanGauge II fuel economy gauge.  Click for details.  

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 11-18-2012, 03:03 PM   #161 (permalink)
EcoModding Lurker
 
Join Date: Jun 2010
Location: Central NY
Posts: 21
Thanks: 0
Thanked 4 Times in 4 Posts
The thing to remember with epoxy is the hardener is not really a catalyst like with polyester resin. The ratio of A to B must be exact since the molecules need to cross link with each other. Extra of either part means molecules lying around with nothing to cross link to. In other words it may feel hard eventually but it won't have the same properties and strength. It may not matter much in a non stressed area of course.

  Reply With Quote
Old 11-18-2012, 04:07 PM   #162 (permalink)
ron
Master EcoModder
 
Join Date: Nov 2011
Location: slo county ca.
Posts: 277

double eagles - '99 Dodge ram slt
Team Cummins
90 day: 19.48 mpg (US)
Thanks: 24
Thanked 17 Times in 16 Posts
the hardener was with poly resin as i recall 1986-7 we made containers for aircraft ,I didnt do the digging the layup dept did that . It was one of there x employees that sabotaged the tank . and without it they didnt work. I didnt know the dif between epoxy and poly thanks JRP3 .
  Reply With Quote
Old 11-20-2012, 01:58 AM   #163 (permalink)
B.O. Zen
 
Join Date: Feb 2009
Location: Folsom, CA
Posts: 190

Pickup - '99 Toyota Tacoma 2wd, Regular Cab, Short Bed
90 day: 34.62 mpg (US)
Thanks: 111
Thanked 125 Times in 54 Posts
The resin got hard enough that I could sand on it, so I decided to call it good and use the part. It's not structural anyway. I mixed up a bit more resin and finished saturating the glass that wraps around the edges (pictures next post) and got started on the other side. If all goes well, should be doing body filler and primer in the next week. I don't expect I'll get much done over Turkey Day weekend.

Oh, I found that epoxy resin does not seem to loosen masking tape along the edge of fiberglass... it might be different with polyester resin, but all the bits of tape I used on this piece are a part of it now. :`}
__________________
  Reply With Quote
Old 11-20-2012, 02:00 AM   #164 (permalink)
B.O. Zen
 
Join Date: Feb 2009
Location: Folsom, CA
Posts: 190

Pickup - '99 Toyota Tacoma 2wd, Regular Cab, Short Bed
90 day: 34.62 mpg (US)
Thanks: 111
Thanked 125 Times in 54 Posts
Oh, I also cut some pieces of lexan and glued them into the air holes in the plastic valence below my bumper! Progress!
__________________
  Reply With Quote
The Following User Says Thank You to a8ksh4 For This Useful Post:
aerohead (11-21-2012)
Old 11-20-2012, 04:20 AM   #165 (permalink)
Prime Directive Violator
 
Join Date: Jun 2012
Location: Mesa, AZ
Posts: 2,394

Bacon - '99 Subaru Forester L
90 day: 27 mpg (US)

Chorizo - '00 Honda Civic HX, baby! :D
90 day: 43.52 mpg (US)
Thanks: 306
Thanked 281 Times in 207 Posts
This has been a very interesting read. Very impressive!
  Reply With Quote
Old 11-20-2012, 11:50 PM   #166 (permalink)
B.O. Zen
 
Join Date: Feb 2009
Location: Folsom, CA
Posts: 190

Pickup - '99 Toyota Tacoma 2wd, Regular Cab, Short Bed
90 day: 34.62 mpg (US)
Thanks: 111
Thanked 125 Times in 54 Posts
Alright, here are some results from last night's work. I had started the other day by pouring resin in the middle of the front of the passenger side panel. Last night I worked resin in around the edges of the front and around the back. Had to just use my rubber gloves to work most of the stuff on the back because it was odd shapes and folds and kinds of messy. All of the surfaces that are visible from outside the truck came out pretty clean.






I found a better way to drape the fabric over the driver side panel so that I don't need to make any cuts, except at the corners to cut down on bulk on the back. It's amazing how much this twill weave can be contoured around weird stuff:


And the resin hardened in the middle of the second panel:


I think that the mix ratio wasn't as bad as I had thought on the first panel. Once the second batch was applied to the rest of the fabric around the edges and onto the back, the middle tightened right up (didn't add any additional resin to the middle). I think that, maybe, having tension on the fabric from getting it wrapped all the way around took some of the give that I was feeling out of the middle of the big smooth front surface.
__________________
  Reply With Quote
The Following 5 Users Say Thank You to a8ksh4 For This Useful Post:
aerohead (11-21-2012), bryson (11-21-2012), KamperBob (11-21-2012), NeilBlanchard (11-30-2012), slowmover (11-22-2012)
Old 11-30-2012, 02:04 AM   #167 (permalink)
B.O. Zen
 
Join Date: Feb 2009
Location: Folsom, CA
Posts: 190

Pickup - '99 Toyota Tacoma 2wd, Regular Cab, Short Bed
90 day: 34.62 mpg (US)
Thanks: 111
Thanked 125 Times in 54 Posts
I got a little more work done on the 2nd panel this evening. It's looking a lot more clean than the first one.


The adhesion isn't going to be super good on the back, but I'll be able to trim out the couple of big wrinkles when it cures. I didn't use any peel-ply type stuff this time. I just wet the fabric down and pulled it around the edges. It seems like the sharp edges came out really clean this way. The peel ply might still be a good idea for any flat surfaces like the back.
__________________
  Reply With Quote
The Following User Says Thank You to a8ksh4 For This Useful Post:
NeilBlanchard (11-30-2012)
Old 11-30-2012, 09:25 AM   #168 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 5,679

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 51.26 mpg (US)
Thanks: 1,157
Thanked 1,269 Times in 762 Posts
Question: what are the weights of the fiberglass fabrics that you are using? Just curious - and where did you buy them?
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 11-30-2012, 12:13 PM   #169 (permalink)
B.O. Zen
 
Join Date: Feb 2009
Location: Folsom, CA
Posts: 190

Pickup - '99 Toyota Tacoma 2wd, Regular Cab, Short Bed
90 day: 34.62 mpg (US)
Thanks: 111
Thanked 125 Times in 54 Posts
The fabric is 8.8oz twill E glass. I also got some 6" wide 9oz stuff that I'm planning on using to back up any corners and edges that I want to be stronger. They're from TAP Plastics.
__________________
  Reply With Quote
Old 11-30-2012, 01:07 PM   #170 (permalink)
Do more with less
 
Join Date: Jul 2010
Location: North Eastern Missouri
Posts: 882

OD - '05 Ford Econoline
90 day: 18.64 mpg (US)

Joetta - '86 Volkswagen Jetta Turbo Oil Burner
TEAM VW AUDI Group
90 day: 49.71 mpg (US)

Benzilla - '85 Mercedes Benz 300D
90 day: 28.08 mpg (US)
Thanks: 55
Thanked 154 Times in 95 Posts
I would recommend that you lay the fabric on the bias. It will conform better. If you use a second layer or more change the angle of the fabric threads to improve overall strength.

__________________
"A man is not finished when he is defeated. He is finished when he quits."
Richard M. Nixon


"The reward of suffering is experience."
Harry S. Truman

“There's no way to rule innocent men. The only power any government has is the power to crack down on criminals. Well, when there aren't enough criminals, one makes them. One declares so many things to be a crime that it becomes impossible for men to live without breaking laws.”
Ayn Rand
  Reply With Quote
Reply  Post New Thread

Thread Tools





Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com