prepreg fiberglass question

[Andrew Sarangan]

I've heard of prepregs which have the resin and hardener separated
within the fabric, which can be activated by applying pressure with a
squeegee or similar tool. I searched the internet but I can only find
the standard premixed prepregs which need to be kept in a refrigerator
and cured at elevated temperatures. Anyone know what I am talking
about or where I can buy this thing?

I am basically looking for a way to avoid having to hand make long
lengths of fiberglass tapes for noncritical applications. But it has
to cure fast at room temperature like any standard epoxy so the
premixed ones won't work.

Thanks!

[cavelamb himself[_4_]]

Andrew Sarangan wrote:
> I've heard of prepregs which have the resin and hardener separated
> within the fabric, which can be activated by applying pressure with a
> squeegee or similar tool. I searched the internet but I can only find
> the standard premixed prepregs which need to be kept in a refrigerator
> and cured at elevated temperatures. Anyone know what I am talking
> about or where I can buy this thing?
>
> I am basically looking for a way to avoid having to hand make long
> lengths of fiberglass tapes for noncritical applications. But it has
> to cure fast at room temperature like any standard epoxy so the
> premixed ones won't work.
>
> Thanks!
>
>
>
>

Prepregs are literally pre-impregnated with catalyzed resin.
They are kept from hardening by being kept at low temperature.

It has nothing to do with pressure - certainty not from
something as flimsy as a squeegee.

Sounds like you need to hit the books.
There are LOTS of tehm.
Try Amazon? :)

Richard
--
(remove the X to email)

[Andrew Sarangan]

On May 12, 9:58 am, cavelamb himself > wrote:
> Andrew Sarangan wrote:
> > I've heard of prepregs which have the resin and hardener separated
> > within the fabric, which can be activated by applying pressure with a
> > squeegee or similar tool. I searched the internet but I can only find
> > the standard premixed prepregs which need to be kept in a refrigerator
> > and cured at elevated temperatures. Anyone know what I am talking
> > about or where I can buy this thing?
>
> > I am basically looking for a way to avoid having to hand make long
> > lengths of fiberglass tapes for noncritical applications. But it has
> > to cure fast at room temperature like any standard epoxy so the
> > premixed ones won't work.
>
> > Thanks!
>
> Prepregs are literally pre-impregnated with catalyzed resin.
> They are kept from hardening by being kept at low temperature.
>
> It has nothing to do with pressure - certainty not from
> something as flimsy as a squeegee.
>
> Sounds like you need to hit the books.
> There are LOTS of tehm.
> Try Amazon? :)
>
> Richard
> --
> (remove the X to email)

I am very familiar with the standard prepregs and how to work with
them (as I indicated on the original post). But the type I am thinking
of is an unusual type. It has the resin and hardener separated by a
thin membrane inside the glass, and when you squeeze it hard the
membrane ruptures and mixes the two components (I think the color
also changes to indicate proper mixing). If you have a reference or
vendor for this item, I would appreciate any info.

[cavelamb himself[_4_]]

Andrew Sarangan wrote:

> On May 12, 9:58 am, cavelamb himself > wrote:
>
>>Andrew Sarangan wrote:
>>
>>> I've heard of prepregs which have the resin and hardener separated
>>>within the fabric, which can be activated by applying pressure with a
>>>squeegee or similar tool. I searched the internet but I can only find
>>>the standard premixed prepregs which need to be kept in a refrigerator
>>>and cured at elevated temperatures. Anyone know what I am talking
>>>about or where I can buy this thing?
>>
>>>I am basically looking for a way to avoid having to hand make long
>>>lengths of fiberglass tapes for noncritical applications. But it has
>>>to cure fast at room temperature like any standard epoxy so the
>>>premixed ones won't work.
>>
>>>Thanks!
>>
>>Prepregs are literally pre-impregnated with catalyzed resin.
>>They are kept from hardening by being kept at low temperature.
>>
>>It has nothing to do with pressure - certainty not from
>>something as flimsy as a squeegee.
>>
>>Sounds like you need to hit the books.
>>There are LOTS of tehm.
>>Try Amazon? :)
>>
>>Richard
>>--
>>(remove the X to email)
>
>
> I am very familiar with the standard prepregs and how to work with
> them (as I indicated on the original post). But the type I am thinking
> of is an unusual type. It has the resin and hardener separated by a
> thin membrane inside the glass, and when you squeeze it hard the
> membrane ruptures and mixes the two components (I think the color
> also changes to indicate proper mixing). If you have a reference or
> vendor for this item, I would appreciate any info.
>

Sorry, Andrew, never heard of them in private hands,


Richard
--
(remove the X to email)

Now just why the HELL do I have to press 1 for English?
John Wayne

[BobR]

On May 12, 9:05*am, Andrew Sarangan > wrote:
> On May 12, 9:58 am, cavelamb himself > wrote:
>
>
>
>
>
> > Andrew Sarangan wrote:
> > > *I've heard of prepregs which have the resin and hardener separated
> > > within the fabric, which can be activated by applying pressure with a
> > > squeegee or similar tool. I searched the internet but I can only find
> > > the standard premixed prepregs which need to be kept in a refrigerator
> > > and cured at elevated temperatures. Anyone know what I am talking
> > > about or where I can buy this thing?
>
> > > I am basically looking for a way to avoid having to hand make long
> > > lengths of fiberglass tapes for noncritical applications. But it has
> > > to cure fast at room temperature like any standard epoxy so the
> > > premixed ones won't work.
>
> > > Thanks!
>
> > Prepregs are literally pre-impregnated with catalyzed resin.
> > They are kept from hardening by being kept at low temperature.
>
> > It has nothing to do with pressure - certainty not from
> > something as flimsy as a squeegee.
>
> > Sounds like you need to hit the books.
> > There are LOTS of tehm.
> > Try Amazon? :)
>
> > Richard
> > --
> > (remove the X to email)
>
> I am very familiar with the standard prepregs and how to work with
> them (as I indicated on the original post). But the type I am thinking
> of is an unusual type. It has the resin and hardener separated by a
> thin membrane inside the glass, and when you squeeze it hard the
> membrane ruptures and mixes the two components *(I think the color
> also changes to indicate proper mixing). If you have a reference or
> vendor for this item, I would appreciate any info.- Hide quoted text -
>
> - Show quoted text -

I have seen what you are discussing in a clay like form but never in
an impregnated glass. The concept sounds great but I can't see how
you would ever achieve a good and consistant mixture.

[Bob Kuykendall]

On May 11, 9:56*pm, Andrew Sarangan > wrote:
> ...I am basically looking for a way to avoid having to hand make long
> lengths of fiberglass tapes for noncritical applications. But it has
> to cure fast at room temperature like any standard epoxy so the
> premixed ones won't work.

For that application I'd be inclined to consider pre-pregging chunks
of cloth with UV-curing vinylester, and sandwiching it between two
sheets of one-mil nylon sheet. Chuck it into a ziploc bag in a dark
cabinet. Then cut strips of tape off the edges and use them at need.
After applying, zap with UV light or just point at the sun.

Thanks, Bob K.

[T.L. Davis]

On Sun, 11 May 2008 21:56:48 -0700 (PDT), Andrew Sarangan
> wrote:

> I've heard of prepregs which have the resin and hardener separated
>within the fabric, which can be activated by applying pressure with a
>squeegee or similar tool. I searched the internet but I can only find
>the standard premixed prepregs which need to be kept in a refrigerator
>and cured at elevated temperatures. Anyone know what I am talking
>about or where I can buy this thing?
>
>I am basically looking for a way to avoid having to hand make long
>lengths of fiberglass tapes for noncritical applications. But it has
>to cure fast at room temperature like any standard epoxy so the
>premixed ones won't work.
>
>Thanks!
>

If this stuff doesn't exist, based on the responses, I would suggest
patenting the concept. Imagine a two (or greater) sandwich of S
glass, with encapsuated layers of resin and catalyst. The fabric is
draped over a male plug (permanent or removable). It is then vacuum
bagged. The compressive force of the vaccuum ruptures the
encapsulations and the binary system begins to mix. A vibrating or
centrifugal base could be used to acheive optimal mixing of the
components. What you could wind up with is a near perfect composite
structure,not dependent on squeegee force or perfect application of
squeegee pressure (impossible given time constraints and the stress
from time pressure).

If it does exist, I'd like to know how to obtain it also.

T.L. Davis

[Maxwell[_2_]]

"T.L. Davis" > wrote in message
...
> On Sun, 11 May 2008 21:56:48 -0700 (PDT), Andrew Sarangan
> > wrote:
>
>> I've heard of prepregs which have the resin and hardener separated
>>within the fabric, which can be activated by applying pressure with a
>>squeegee or similar tool. I searched the internet but I can only find
>>the standard premixed prepregs which need to be kept in a refrigerator
>>and cured at elevated temperatures. Anyone know what I am talking
>>about or where I can buy this thing?
>>
>>I am basically looking for a way to avoid having to hand make long
>>lengths of fiberglass tapes for noncritical applications. But it has
>>to cure fast at room temperature like any standard epoxy so the
>>premixed ones won't work.
>>
>>Thanks!
>>
>
> If this stuff doesn't exist, based on the responses, I would suggest
> patenting the concept. Imagine a two (or greater) sandwich of S
> glass, with encapsuated layers of resin and catalyst. The fabric is
> draped over a male plug (permanent or removable). It is then vacuum
> bagged. The compressive force of the vaccuum ruptures the
> encapsulations and the binary system begins to mix. A vibrating or
> centrifugal base could be used to acheive optimal mixing of the
> components. What you could wind up with is a near perfect composite
> structure,not dependent on squeegee force or perfect application of
> squeegee pressure (impossible given time constraints and the stress
> from time pressure).
>
> If it does exist, I'd like to know how to obtain it also.
>
> T.L. Davis

Something sensitive enough to be ruptured by a vacuum bag would be real
susceptible to handling damage. A single blem in a large panel could scrap a
lot of expensive material. The UV-curing vinylester would seem more user
friendly.