What plastic?

[cse...@mts.net]

What is RIM or RRIM plastic exactly. Don't need to know how it is
injected or that RRIM is reinforced or that it's black. I need to
do some repairs and yes, SEM urethane should be an OK repair and so
should windshield urethane adhesive. But what is the stuff?

Pete

[Mr Potatohead]

You get your answer yet, Pete?

[cse...@mts.net]

On Thu, 23 Oct 2008 14:54:18 -0400, Mr Potatohead <bo...@home.con>
wrote:

I most certainly have not. And how come you don't have that answer.
I thought you knew most everything Fiero.

P

[Mr Potatohead]

Hell, what I don't know would fill several books. I'm a
bit surprised though that no one has answered you. There
was a good background on the different plastics used on
Fieros a while back. I'll see if I can find it.

[Les Benn]

There are two kinds of plastic on a Feiro Body one is the stuff that the
fenders are made of and the other is the flexible stuff for the bumpers.

I think the RIM stuff is the bumper plastic

<cse...@mts.net> wrote in message news:48fd24d3...@news.mts.net...

[Mr Potatohead]

Les Benn wrote:
> There are two kinds of plastic on a Feiro Body one is the stuff that the
> fenders are made of and the other is the flexible stuff for the bumpers.
>
> I think the RIM stuff is the bumper plastic
>

Ahh, Les,

How are you, these days?

Actually I understand that there are 5 kinds of plastic:
1. hard, flexible panel (doors),
2. hard, unflexible (hood, truck and rear clip),
3. very flexible, rubber-almost, (bumpers)
...and two others, I forget what they are.

Pete wants specifics, though, and I cannot find out
unless I wander into that maze called Pennocks. I was
rather hoping that PRand or someone else who monitors
here and knows about this stuff would step in. He
probably has already found out though.

Googling "RRIM plastic" brought up over 6500 sites and
I'm sure that by the time we found out about it within
the Fiero community, Pete will have found out that which
he needs to know. Huh? :-)

[cse...@mts.net]

>Actually I understand that there are 5 kinds of plastic:
>1. hard, flexible panel (doors),
>2. hard, unflexible (hood, truck and rear clip),
>3. very flexible, rubber-almost, (bumpers)
>...and two others, I forget what they are.
>

RIM is urethane (bumpers)
RRIM is fiberglass reinforced RIM (door, front fenders, rear
quarters)
SMC is sheet molded compound (all the hard parts)
TPO is thermo plastic olefin (rocker panel) No mention of repair
procedures for this stuff.
Interior plastic may be Vinyl, ABS, or polypropolene

I found out all this stuff reading my Helms manual. I'm prepared to
swear a solomn oath that when I read this manual some years ago, the
hard stuff was the RRIM - turns out it's SMC. The repair I want to do
is on the SMC, and that's the stuff I was really enquiring about.
Seems you can use damn near anything to do a repair including
polyester body filler on the SMC. Sure would be nice to use the most
compatible repair materials though.

Apollogies if I have led you down the garden path on the names of the
plastics. I'm sticking to this new story.

So, what is SMC? Recycled plastic bottles, old tires, dead cats,
used diapers, what?

Pete

[B Fuhrmann]

I have never found a specific material listed for the Sheet Molding Compound
used in the Fiero but the family is made of a thermoset material mixture
(base and catalyst) around a fiber reinforcement. The materials are molded
into a soft sheet that is then shipped to where it is formed and heated to
lock it into shape.
You won't be able to match the thermoset resin. It is not something that is
available for use outside of a factory that has the proper curing (heat
induced).

In my searches today, I found a message I left in '98.

> Here's something Paul Vargyas originally wrote...
>
> SMC
> Sheet Molded Compound
> RRIM
> Reinforced Reaction Injection Molding
> RIM
> Reaction Injection Molded
> TPO
> Thermo Plastic Olefin is used for the rocker panels.

Thanks for posting the list. None of these are "fiberglass" which is usually
used to refer to fiber glass mat in epoxy.

The reinforcement within the RRIM and SMC parts may be glass or other
fibers, but the fiber content will be a much smaller percent than in
"fiberglass" and the main plastic will not be an epoxy.
According to the 1988 service manual, glass fiber is used as the
reinforcement in the RRIM.

RIM and SMC refer to the method of making the parts. Proper repair requires
knowing the type of plastic used to make the part.
The service manual does not indicate the plastics involved, but gives
proper materials to use with each.

All parts must be cleaned of all dirt, wax, grease, and silicone (silicone
may be on the parts from the molding process).

SMC
If there is only surface damage, polyester body filler can be used.

If support is needed, use epoxy resin or other structural adhesive to hold
the support material and patch.
Epoxy and fiberglass cloth are recommended.

If structural strength is needed, use the procedure for RIM.

RRIM and RIM
For non structural repairs:
Use 180 grit paper to remove all paint around the repair area.
The repair material must not be applied over paint.
Use 50 grit to enlarge the damaged area and create a 1" wide tapered area
to allow the repair material to bond to the base plastic.
Use aluminum autobody repair tape (3M 06935 or 06936 or equiv) on the back
of any puncture to support the repair material.
Use 3M Flexible Parts Repair Material #05900 or 3M brand Structural
Adhesive #08101 or equivalent (these are two part compounds that need to be
mixed like epoxy).
Spread a thin coating of the repair material over the entire repair area.
Then build it up to a level slightly above the surrounding area.
Allow to cure for 30 minutes.
More of the repair material or 3M Flexible Parts Putty #05903 can be used
to fill in any remaining pits in the surface.
Do the usual sanding and painting.

Structural repair
Align and immobilize the repair area with body tape and spring clamps.
Sand the back of the repair area with 50 grit disk.
Cut a piece of fiberglass cloth to be at least 1 1/2 inch larger than the
damage.
Prepare and spread a 1/8" thick layer of flexible adhesive over the repair
area.
Apply the fiberglass cloth into the adhesive.
Immediately spread more adhesive over the cloth so that the weave is filled.
Let the adhesive cure and repair as for non-structural repair.

--
Bill Fuhrmann

<cse...@mts.net> wrote in message news:4903d62b...@news.mts.net...

[Les Benn]

doing good here tater. I hope you are having tons of fun.

"Mr Potatohead" <bo...@home.con> wrote in message
news:X1KMk.13470$xs1....@newsfe05.iad...

[Mr Potatohead]

Les Benn wrote:
> doing good here tater. I hope you are having tons of fun.
>
>

I'll start having fun again when this election is over
and these silly people get back to work in Washington.

But other'n that, my Fieros are all in the barn except
one and I'm ready for snow. Bring it on!! Yahhh! :-)