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-   -   Reinforce interior plastic? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/reinforce-interior-plastic-1033384/)

driftxsequence 04-24-13 10:43 AM

Reinforce interior plastic?
 
I recently grabbed a full grey interior to get rid of my red / poop green interior. Upon removal I broke a few tabs, but not nearly as much as I expected. For those few I plan on getting a plastic epoxy and molding the metal clips right into the epoxy. However, One of the A-pillar trims cracked half way. I could super glue it from behind, which is no problem but the whole piece is rather flimsy. Is there any good way to maybe fiberglass the backside or run something the length to reinforce the piece from cracking again?

I did find this post which I may be useful for repairing the crack, but not strengthening the whole piece. https://www.rx7club.com/3rd-generati...w-pics-828143/

jjwalker 04-24-13 10:51 AM

If you don't want to fiddle with fiberglass, you can use bondo. Bondo dries incredibly hard

Prep the surface with some sanding, thin coat of bondo and boom, done.

j9fd3s 04-24-13 11:10 AM

i've found acrylic cement works really well on most of the FC interior

Brigdh 04-24-13 03:52 PM


Originally Posted by j9fd3s (Post 11448689)
i've found acrylic cement works really well on most of the FC interior

I know I've snapped some of the yellow plastic tabs that hold the gauge surround to the dash, which I've been meaning to fix. Do you know if acrylic cement works well for that area?

FelixIsGod29X 04-24-13 03:58 PM

JB weld that shit.

Aaron Cake 04-25-13 08:52 AM

I just buy new trim at the dealer. It's not worth the time and trouble to try and repair 30 year old sun baked plastic. For example, the S4 stereo surround is about $100. I went through 3 junkyard surrounds at $20 a piece in the span of a few years. And spent hours reinforcing and gluing them so they would "last" only to have them break somewhere else or the repair to fail. What's even the point when the new piece is $100 and will last another 20 years without issue?

In 20 years when this trim is getting rare at the dealer then we may have to look at repairing it...

To fix the broken cluster surround tabs on the dash, just make some new tabs out of 1/8" aluminum. Drill and tap the screw holes. Then adhere to the dash using strong epoxy and reinforcing cloth. See picture below:

http://www.aaroncake.net/misc/rebuil...d%20Mounts.jpg

clokker 04-25-13 09:30 AM


Originally Posted by driftxsequence (Post 11448661)
One of the A-pillar trims cracked half way. I could super glue it from behind, which is no problem

"No problem" but no good, either.
Most of our interior plastic is ABS and it needs a solvent based adhesive.
You can make your own ABS patching material out of ABS chips and acetone...mix together in a sealed glass jar, the acetone will dissolve the ABS and make a paste.
Thin or thicken the paste by adding more acetone or plastic to get the consistency you want (I like it to be maple syrupy...).
Prep the area around the repair by swabbing with pure acetone (this starts the melting process) and then apply (any way that seems suitable) the paste/syrup.

If you want easier, Weldon #16 medium bodied solvent cement will work but does not add the reinforcement possible with the thicker homemade stuff.

Customisbetter 04-25-13 09:46 AM

^Clokker you just made my day! Gonna start on my interior cracks tonight!

clokker 04-25-13 09:54 AM

2 Attachment(s)
This is an a-pillar I repaired on my car:
Attachment 674167

Attachment 674168

Depending on the ABS you're melting for the "glue", it may take a few days to prepare.
The smaller/finer/thinner the chips, the faster they'll melt.

driftxsequence 04-25-13 10:15 AM

Your pillar trim clip was broken as well :P Did you use ABS pipe commonly used for plumbing? Where can I find some? This looks like a nice little project. I dont want a rattling anymore.

Rob XX 7 04-25-13 10:21 AM

a 2 part adhesive would do the trick, these guy by many names you see them in the sealant section of the store with the plungers on them. They dry fast. I use structural urethane but its a special gun to dispense it not sure if they have small 2 plunger disposable kits

clokker 04-25-13 10:39 AM


Originally Posted by driftxsequence (Post 11449711)
Your pillar trim clip was broken as well :P Did you use ABS pipe commonly used for plumbing? Where can I find some? This looks like a nice little project. I dont want a rattling anymore.

Yes, the clip is broken but it doesn't matter since I swapped to manual belts (which removes the mousetrack that the clip fastens to...).
Yes you can- and I have- use(d) ABS plumbing pipe, the trick is to turn it into fine chips. I turned mine down on a lathe and got fine long "hairs" of plastic which melted down quite fast.
Larger chunks will just take longer (sometimes days, during which you may need to add more acetone to keep the mix relatively thin).

Rob XX 7 04-25-13 12:35 PM

what is ABS plumbing pipe? is that like PVC?

jjwalker 04-25-13 12:43 PM

ABS and PVC are two different types of plastic.

http://en.wikipedia.org/wiki/Acrylonitrile_butadiene_styrene
http://en.wikipedia.org/wiki/PVC

clokker 04-25-13 01:37 PM

ABS plumbing stuff is usually black, PVC is white.


Mostly.


/newt

Rob XX 7 04-25-13 09:01 PM

I didnt know they sold abs plumbing pipe. I know abs is different than pvc

pistolgrip 04-26-13 12:31 AM


Originally Posted by Aaron Cake (Post 11449637)
I just buy new trim at the dealer. It's not worth the time and trouble to try and repair 30 year old sun baked plastic. For example, the S4 stereo surround is about $100. I went through 3 junkyard surrounds at $20 a piece in the span of a few years. And spent hours reinforcing and gluing them so they would "last" only to have them break somewhere else or the repair to fail. What's even the point when the new piece is $100 and will last another 20 years without issue?

In 20 years when this trim is getting rare at the dealer then we may have to look at repairing it...

To fix the broken cluster surround tabs on the dash, just make some new tabs out of 1/8" aluminum. Drill and tap the screw holes. Then adhere to the dash using strong epoxy and reinforcing cloth. See picture below:

http://www.aaroncake.net/misc/rebuil...d%20Mounts.jpg

I'm with Aaron on this on in most every respect. :icon_tup: The one exception, I drilled a pilot hole in the yellow inner cluster shell and then attached the aluminum strips with a self taping screw.

Constant bombardment by the sun simply makes plastic more and more brittle

clokker 04-26-13 07:57 AM


Originally Posted by Aaron Cake (Post 11449637)
I just buy new trim at the dealer. It's not worth the time and trouble to try and repair 30 year old sun baked plastic.]


Originally Posted by pistolgrip (Post 11450553)
I'm with Aaron on this on in most every respect.

Me too, and the minute either you or Aaron donate new plastic to my project, I'll install it.

About the dash...
I agree that UV exposure has a deleterious effect but the fact is that the basic design is flawed and will inevitably break.
Those lower switch bezel tabs for instance...no sunlight is harming them, they break because they are flimsy little tabs cantilevered off the edge with no support or bracing.

My5ABaby 04-29-13 12:28 PM

I fiberglassed the entire back side of both of my a-pillars. I've had them in and out numerous times and haven't had any cracking from either.


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