Plastic Deathgrip Handles?

The plastic handle on the CF base is pretty stiff actually. When I had
a plastic base that was where all the flex came from.


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jrdugueod wrote:
Strength is not the only benefit of CF, it is very stiff making hopping
easier.


In all actuality carbon fiber really isn't that rigid, yes it is far
superior to the plastics used but aluminum is stiffer, about twice that
of carbon fiber!

Carbon fiber is stronger and lighter, But not as tough as aluminum.

So if rigidity is really that important why don't you use an aluminum
seat-base?

Some Proof!

This is 15-5 steel.
18143

This is Ti-6AL-4V Titanium
18145

This is 7050 Aluminum
18144

My dad has the cart for carbon fiber but it's number is around 5.

My personal opinion aluminum would be better than carbon fiber (as a
seat-base) and titanium would be better yet.

For the sake of it the plastic probably has an Elastic Modulus of 1 or
2. (I don't know what plastic is used so I won't guarantee that)


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Joe2005

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Evan Byrne wrote:
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if u've ever worked with carbon fiber, u'll understand why aluminium
will never be as good for a seat base.

Aluminium first has plastic properties. So when enough force is applied
it will bend, weakening it and rendering the base pointless.

Carbon fiber will elastically deform a tiny weeny bit, and then break.


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brendan
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brendan wrote:
if u've ever worked with carbon fiber, u'll understand why aluminum will
never be as good for a seat base.

Aluminum first has plastic properties. So when enough force is applied
it will bend, weakening it and rendering the base pointless.

Carbon fiber will elastically deform a tiny weeny bit, and then break.


As I stated before carbon fiber *_IS_* stronger,
just not as rigid.

So what do you want out of a seat base rigidity or strength? This is
a serious question.

And what do you mean elastically deform a tiny weeny bit, then break?
Carbon fiber is flexible (but springs back). So are you saying that
it's yield tolerance is low and will break shortly after deforming?


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Joe2005

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Evan Byrne wrote:
So use a shock frame and learn to take the force with your butt? Too
hard to do? I think not!
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Joe2005 wrote:
As I stated before carbon fiber *_IS_* stronger,
just not as rigid.



Yes, but you can shape carbon fiber to be rigid in the directions you
want it to be. Just like a tube or I beam is more rigid than a flat
sheet. Design the part right and you can make it rigid where it needs
to be.

You could make a seat base out of aluminum. But the machining to get
it in the same shape as the CF or plastic seat base would be expensive
(fancy CNC milling). Or you could cast it, but cast parts aren't as
strong as the same part machined from a block of aluminum. Forging is
going to be expensive as well due to the die costs.


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i still like the viscount seat for trials, fits my hand well for seat
out, is super stiff and sturdy, accepts all handles with self tapping
screws, only downside is, it's heavy. hell i even like sitting on it
more than a torker lx seat.


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Seems like since plastic bases do seem to last some period of time
before they broke, some design changes could make them much stronger,
and yet still keeping the price -way- down from carbon fiber.

If you all remember fugeo's old seat reinforcment, this is a great way
to go. Its absolutly tank proof, and its cheap. It would be interesting
to see a company like k1 or kh to make a sweet (stock) part like this.
It would lengthen the lives of the seats almost to that of a carbon
base and could be way cheaper, light too, seeing as how light they can
get aluminum posts these days.


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carbon fiber is elastic (meaning it deforms plastically but springs back
into place)

but it does not deform plastically at all (or hardly any)

This is not necessarily ideal for a seatbase since more rigidity would
be better, but a metal seat would bend (plastically) unless it was very
thick then weight is involved, and manufacturing costs.... You would
need a bend in the metal and this owuld be expensive to
mould/bend/forge/cnc out


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brendan wrote:
carbon fiber is elastic (meaning it deforms plastically but springs back
into place)

but it does not deform plastically at all (or hardly any)

This is not necessarily ideal for a seatbase since more rigidity would
be better, but a metal seat would bend (plastically) unless it was very
thick then weight is involved, and manufacturing costs.... You would
need a bend in the metal and this owuld be expensive to
mould/bend/forge/cnc out



So your saying it's flexiable but dosen't deform from it's origional
shape. Gotcha.


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Joe2005

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Evan Byrne wrote:
So use a shock frame and learn to take the force with your butt? Too
hard to do? I think not!
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john_childs wrote:
Yes, but you can shape carbon fiber to be rigid in the directions you
want it to be. Just like a tube or I beam is more rigid than a flat
sheet. Design the part right and you can make it rigid where it needs
to be.

You could make a seat base out of aluminum. But the machining to get
it in the same shape as the CF or plastic seat base would be expensive
(fancy CNC milling). Or you could cast it, but cast parts aren't as
strong as the same part machined from a block of aluminum. Forging is
going to be expensive as well due to the die costs.


I'm pretty handy with metals but I don't know much about composits.

So that means I understand what you mean about the Aluminum seatbase
but being more expesnive (more overhead = gotta make a LOT to keep the
price down)...But I don't get what your saying you can make the carbon
fiber to be rigid in the direction you want it to be. Could you try
and explain this a little more clearly.


--
Joe2005

*Come To The Dark Side* we have cookies!

Evan Byrne wrote:
So use a shock frame and learn to take the force with your butt? Too
hard to do? I think not!
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