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Old 07-31-2010, 02:07 PM   #11
ebrabaek OP
Beastly Adventurer
 
Joined: Jan 2010
Location: El Paso,NM
Oddometer: 4,074
Heat testing is done.....

I try to stick with 2 main epoxy applications for simplicity. This one.....
http://cgi.ebay.com/EPOXY-RESIN-CRYS...item483544bccc

And this one.................
http://cgi.ebay.com/EPOXY-RESIN-HIGH...item483836807f

First one is one of the clearest transparent epoxy I have ever used. That is what was used in the CF cover in my other thread. It is extremely strong......and I have used it in applications up to 250 deg. F. with great results. It was my first choice, since it is extremely simple.... Mix...pour...your done. But as I started working on the foam mold..... I got concerned about the heat generated in the proximity to the header, and catalytic converter. Perhaps it is dumbfounded..... But I decided to use the high epoxy instead. It can handle temps of up til 400 deg.F. The trouble is that it need post curing heat treatment. I found that I can " cheat" the post cure schedule.... by leaving it in the sun in the hot desert..... for 4 hrs......That will yield around 200 deg.F. I also have found in earlier testing that once cured.....The max hte ( high temp) pox is stiffer and stronger than the max. clr. So results of the heat foam test........
After 1 hr in the sun...... 180 deg.F.............. No stress on the foam....


Then....under the heat lamp.......and at 290 deg. F. the foam began giving......


That is good news....... So I plan on 4 hrs in the sun.......then to elevate that up to 250 with the heat lamp for a few hrs.

Then it was on to the cast.......Smoothing out the corners......Since Composites don`t like sharp curves. There where a few gaps in between the foam, and the four holes I drilled for the lower mounts...... I filled them with this great stuff. Ever played with play dough..... Modelervoks.... For you fellow scandinavians...... This is an epoxy blend that after you mold it.....like clay hardens, and is tremendously strong.......


Then you gather the Honeycomb material........


Cut 3 strings......and put them in the desired position.......


Mark`em.......


Cut a v notch channel, and fill the very botom with the emc.........


Mold is now ready for it`s first and only cast........ After 4 layers of parafilm.....




There are a few things to note here........ It is properly not a necessity to use the honey comb construction. The impact protection necessary does not come from the honeycomb layup. That does just make this piece tremendously stiff, and I though I`d show it....and as of how to. But if it intimidates you.......Just skip that step. I created the cast with 1/2 inch clearance to the cat, and 3/4 to the header. I believe that if you bring that out to 1 1/4 inch.... you will be ok to use the max clr ( low temp epoxy)..... But only way to know.... Is to cast one.....
Ahhhhhh.... the labor of love......To spend two days .....although not continuously..... to create something that will be destroyed.......is sort of a funny thing. Even with the release agent...( parafilm).... I`m sure that when yanking the piece of the cast.... the foam will disintegrate.......
I always wait overnight with bigger projects...... Just to let it sit......perhaps I forgot something..... Something can be done better.....etc...
So until tomorrow.......



Erling
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