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ghostwalker · 06-02-2011, 11:37 AM

hmmm...I'll split this up

palemelanesian
nope brakes weren't stock the previous owner swapped them from a 99 integra I had to replace them because the car sat for a year and a half while he was deployed. Now that they're fixed I love them.
finger measurement might very a bit I lift steel all day at work and mine are rather thick.

California
nice FE!
shop manual ....sweet
the the rear seat stuff I was talking about in that magazine was a delete. The thing that was so funny to me was you spend $300, lose the ability to carry rear passengers, and save 3lbs of weight. I do have to admit it did look nice but so does the original backseat and I think i would rather drag the 3lbs then spend the $300 for it. There was a lot of plywood in it. If I fabbed my own I was thinking more along the lines of aluminium panels with lightning holes. Covered in color-matched carpet to the interior like if the factory did a 2 seater. I don't know if I will do it sunken for extra cargo and reduced weight or even with the hatch area for a better look.

Splashing 101
making a fiberglas part by creating a mold from an original part is called splashing. It sounds simple but the devil is in the details
1. shrinkage- a part cast from this style of mold will be smaller then the original. epoxy resins shrink less then polyester but they do shrink.
2. lockins- all those channels and lips on car body parts that are no problem in sheetmetal can be a real pain when you're trying to make a mold or cast a part. They can lock the mold onto the original part to where you can't get it off with messing up one of them. To avoid that you have to make a multipart mold and come up with a method of aligning them while making the mold and realigning for casting the part. The worse your alignment the more patching and sanding you will have to do. If it's truly bad then your unlikely to ever get a part that looks worth a damn.
3.mold release- If anyone is going to try this method make sure to polish your mold with a good wax like carnuba and use a mold release like PVA(polyvinyl alcohol).
4. resources-There's a couple of decent books of making fiberglas car parts (I have one by John A. Willis), if you google chavants modeling clay they have some videos on fiberglas molding (you can substitute wood, bondo, plaster for clay you just have to use rougher tools like sanders. Probably the best book I've ever seen on mold making is thurston james's "the prop builders molding and casting handbook." If you want to get your feet wet with mold making start there and if your going to to do fiberglas use use a good epoxy resin (try a boat supply place) polyester sucks.
I use these as references since I learned how to do most of this stuff as an aircraft structural mechanic and as an industrial model maker.
5. cloth- spend the extra money for a tight weave fiberglas cloth. Something like a nice 5 ounce and cross lay (30 or 45 degrees) layers it so the so the threads of 2 layers aren't in line with each other.
6. Use a respirator rated for resins and good latex or vinyl gloves

I've seen some pretty rough looking wheel arch covers on this site (sorry guys) that would probably look nice if they were done in glas. Making nice curves ,I believe, is much easier in it then in most other materials.

What I was ranting about in my original post was that "dry carbon fiber" does save a lot of weight because it's pre-preg with exactly the correct amount of resin and it's ALL carbon. Say same strength at 15% of the weight of the original part. What they were selling was one layer of carbon backed up with fiberglas (random fiber mat at that read: crap glass) for like $700 for a hood. Their part weighed half as much as the original and you had to dig for that info. My contention is a woven cloth/ epoxy resin could be made just as strong if not stronger at the same weight. I made a 1/2 inch thick seat ring like this for a prototype and we couldn't destroy it with a 10 lb sledge. Also since it would be all the same material it would swell and shrink with temp changes better and be less likely to delaminate. I think they're just taking advantage of kids who hear "carbon fiber" and reach for their wallets without checking the details and I think it's sad.

okay I'm done ranting thanks for the input guys I'll tape the ride height soon-GW

06-02-2011, 11:37 AM	#9 (permalink)
ghostwalker EcoModding Lurker Join Date: Apr 2010 Location: texas Posts: 24 ghost's gocart - '97 honda civic cx Thanks: 2 Thanked 6 Times in 4 Posts	hey guys hmmm...I'll split this up palemelanesian nope brakes weren't stock the previous owner swapped them from a 99 integra I had to replace them because the car sat for a year and a half while he was deployed. Now that they're fixed I love them. finger measurement might very a bit I lift steel all day at work and mine are rather thick. California nice FE! shop manual ....sweet the the rear seat stuff I was talking about in that magazine was a delete. The thing that was so funny to me was you spend $300, lose the ability to carry rear passengers, and save 3lbs of weight. I do have to admit it did look nice but so does the original backseat and I think i would rather drag the 3lbs then spend the $300 for it. There was a lot of plywood in it. If I fabbed my own I was thinking more along the lines of aluminium panels with lightning holes. Covered in color-matched carpet to the interior like if the factory did a 2 seater. I don't know if I will do it sunken for extra cargo and reduced weight or even with the hatch area for a better look. Splashing 101 making a fiberglas part by creating a mold from an original part is called splashing. It sounds simple but the devil is in the details 1. shrinkage- a part cast from this style of mold will be smaller then the original. epoxy resins shrink less then polyester but they do shrink. 2. lockins- all those channels and lips on car body parts that are no problem in sheetmetal can be a real pain when you're trying to make a mold or cast a part. They can lock the mold onto the original part to where you can't get it off with messing up one of them. To avoid that you have to make a multipart mold and come up with a method of aligning them while making the mold and realigning for casting the part. The worse your alignment the more patching and sanding you will have to do. If it's truly bad then your unlikely to ever get a part that looks worth a damn. 3.mold release- If anyone is going to try this method make sure to polish your mold with a good wax like carnuba and use a mold release like PVA(polyvinyl alcohol). 4. resources-There's a couple of decent books of making fiberglas car parts (I have one by John A. Willis), if you google chavants modeling clay they have some videos on fiberglas molding (you can substitute wood, bondo, plaster for clay you just have to use rougher tools like sanders. Probably the best book I've ever seen on mold making is thurston james's "the prop builders molding and casting handbook." If you want to get your feet wet with mold making start there and if your going to to do fiberglas use use a good epoxy resin (try a boat supply place) polyester sucks. I use these as references since I learned how to do most of this stuff as an aircraft structural mechanic and as an industrial model maker. 5. cloth- spend the extra money for a tight weave fiberglas cloth. Something like a nice 5 ounce and cross lay (30 or 45 degrees) layers it so the so the threads of 2 layers aren't in line with each other. 6. Use a respirator rated for resins and good latex or vinyl gloves I've seen some pretty rough looking wheel arch covers on this site (sorry guys) that would probably look nice if they were done in glas. Making nice curves ,I believe, is much easier in it then in most other materials. What I was ranting about in my original post was that "dry carbon fiber" does save a lot of weight because it's pre-preg with exactly the correct amount of resin and it's ALL carbon. Say same strength at 15% of the weight of the original part. What they were selling was one layer of carbon backed up with fiberglas (random fiber mat at that read: crap glass) for like $700 for a hood. Their part weighed half as much as the original and you had to dig for that info. My contention is a woven cloth/ epoxy resin could be made just as strong if not stronger at the same weight. I made a 1/2 inch thick seat ring like this for a prototype and we couldn't destroy it with a 10 lb sledge. Also since it would be all the same material it would swell and shrink with temp changes better and be less likely to delaminate. I think they're just taking advantage of kids who hear "carbon fiber" and reach for their wallets without checking the details and I think it's sad. okay I'm done ranting thanks for the input guys I'll tape the ride height soon-GW