The Lotus Cars Community banner
1 - 9 of 9 Posts

·
Registered
2006 Elise
Joined
·
492 Posts
Discussion Starter · #1 ·
The splitter that came with the car is cracked at the front edge, so I bought a Moto-Build replacement. I don't have the time to learn how to repair it. So if anybody wants to buy it, it's available.
Looking at the photos, the old one is not as shiny, and the underside appears very different than the Moto-Build.
Thanks,

1293706
1293707
 

·
Premium Member
Joined
·
4,135 Posts
I may be wrong but that looks like a splitter from Wirewheel. Hays sold me one a few years ago. Splitters are like brake pads. Expendable.
 

·
Registered
'05 Elise, LRG
Joined
·
20 Posts
Any functional difference(s) between the 2 types?
Thanks,
For this purpose not really
To provide a little more detail on this, one of the goals of glass reinforcement is to provide increased strength and durability to the resin system. Under stress, the resin transfers the force to the fibers in the composite structure, and the glass fibers then support the majority of the load since the resin is softer and weaker. Since the resin is just holding everything together, we can think about how the chopped glass vs the weave behaves by pretending the resin doesn't exist. If you were to take a pile of 3" long glass fibers and pull on piece of that pile you might get a small wad of fibers that would break off the main pile just because they were tangled up enough in the piece you pinched. However, if you take a woven piece of cloth and pull a corner, you're likely to take the whole thing with you. The woven glass fibers are stronger as a system than the chopped glass, because the fibers are longer and transfer force between themselves more effectively.

So functionally, if the resin system is the same a woven reinforcement will always be stronger than random oriented reinforcement. Think plywood vs. OSB.

However, one of the limitations of chopped glass mat is that it's not compatible with epoxy resin systems. Epoxy resins will almost always give you superior mechanical properties compared to any alternative system, especially with how precisely they can be tuned. That includes strength, durability, chemical resistance, impact resistance, and UV resistance, among others.

For these two splitters, the Motobuild is using the chopped fiber because it's cheaper and easier to work with. And as MCD noted, it's probably "good enough" for this purpose. It might be more susceptible to impact damage, but that depends on which resin each is using as well, so that can't be said with any sort of definitiveness.
 

·
Administrator
Joined
·
8,356 Posts
You can get epoxy compatible CSM that is stitched vs with binders. You can use epoxy still but the binders don't dissolve and appear white.
The higher your fiber to resin ratio is the stronger your product will be. This is one reason pre preg is often used because a stronger lighter weight product can be engineered and produced.
There are three main types of resins with polyester at the bottom in terms of strength and cost and epoxies at the top. There is also vinyl esters which offer the best bang for the buck in many applications.
Here's a really informative link on resins Learning Center - About Resins
 
  • Like
Reactions: Darren Donovan

·
Registered
'05 Elise, LRG
Joined
·
20 Posts
You can get epoxy compatible CSM that is stitched vs with binders. You can use epoxy still but the binders don't dissolve and appear white.
The fun method I learned about a few years ago is reaction injection molding, but that's specialty above specialty. Basically you mix and cure your resin inside the auger. The risk is obviously that you get a runaway exotherm and cure the resin inside your machine, seizing it up completely. There's research being done on how to control the orientation and distribution of the composite filler material (be it glass or nanoparticles) during the process, since fibrous materials will tend to orient with flow direction - obviously not ideal for isotropy.
 

·
Administrator
Joined
·
8,356 Posts
The fun method I learned about a few years ago is reaction injection molding, but that's specialty above specialty. Basically you mix and cure your resin inside the auger. The risk is obviously that you get a runaway exotherm and cure the resin inside your machine, seizing it up completely. There's research being done on how to control the orientation and distribution of the composite filler material (be it glass or nanoparticles) during the process, since fibrous materials will tend to orient with flow direction - obviously not ideal for isotropy.
Before getting into infusion I first learned about exotherm while anchored out and was joining inner and outer skins on my boat after the balsa core got waterlogged. I had a diamond pattern drilled in the deck and after thoroughly drying, mixed some WEST 105/205 and cabosil. I 3/4 filled each hole at at that age just didn't think about the hot sun and 100 deg temps next thing I knew I had six smokestacks going on deck and the boat was locked. Sure wish I had drank more beer the night before damn near lost the boat lol.
 
1 - 9 of 9 Posts
Top