Need Advice on Repairing Dash Pad Plastic on a 96

[Greg G.]

Hi Folks:

The plastic framed instrument panel pads are fairly delicate on a C4. I have one where someone had it off sometime in the past and the thin plastic framework was broken in the process. I tried CA adhesive in a repair attempt but it broke at the repair site as soon as I started tightening the screws. I need an adhesive that is either stronger or forms a stronger bond to whatever the type of plastic the pad substrate is made of. Anybody had any success with this?

Thanks, Greg

[Joe L.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Hi Folks:

The plastic framed instrument panel pads are fairly delicate on a C4. I have one where someone had it off sometime in the past and the thin plastic framework was broken in the process. I tried CA adhesive in a repair attempt but it broke at the repair site as soon as I started tightening the screws. I need an adhesive that is either stronger or forms a stronger bond to whatever the type of plastic the pad substrate is made of. Anybody had any success with this?

Thanks, Greg

Greg-----


I THINK the dash pad substrate material for C4's is linear polyethylene or polypropylene plastic. These are among the most difficult of all plastics to bond to and/or repair. I believe that Permatex/Locktite now has an adhesive available that will repair such plastics.

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Greg, I'm up against the same thing with my '90. (We have the same style dash.)

I bought Kurt Lammons' book on how to repair plastics. He's quite thorough and informative on ABS, PVC, SMC, and the various bumper materials.

As a matter of fact, I'm going to call the guys at his company in a few minutes because I have delamination of the foam/vinyl interface from the ABS substrate.

If you've removed the pad from the dash structure, most likely there is no "ABS" or other identifying marks. I think those marks are on the side that the foam is bonded to. (Could be mistaken here but that's my best guess.)

I've actually purchased the last one in existence and expect that they'll be shipping it today. It also has a bit of delam at the leading edge, that is, the edge just under the windshield. At least none of the tabs on the new one are broken.

I'll post what I learn from Lammons and company.

[Greg G.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Thanks for the excellent info Bruce and Joe! Mine is broken at a couple of the attachment points on the plastic frame or the substrate where the instrument panel pad assembly attaches to the windshield frame. Identifying the plastic type will be critical to obtaining a strong repair and I will be very interested in finding out what it is. I may also be interested in finding a copy of that book too Bruce as it sounds like it should be in the toolbox of every C4 owner! With broken plastic around the attachment points on the substrate the instrument panel upper trim pad cannot be securely mounted to the car. This one is primarily broken adjacent to the defroster duct where there are locations for two screws that attach it to the windshield base. What is most likely the type of plastic I am dealing with here and what would be the best recommended repair method?

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Greg, let me type this out quickly, then I'll google Kurt's book and post the particulars but...and here's the good news: he shows you, in text and photos, precisely how to reconstruct those tabs.

In the next few minutes, I'm going to close my door, call over there and chat with those guys, then return here and post what I've learned along with the exact title and isbn of Kurt's book.

There are a whole slew of us out there with this cover and it's time we learned how to repair/restore them.

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Kurt is in a meeting at the moment but I was told to call back in an hour.

Meanwhile, here's a link to his book: (admins, can I do this?)

http://www.amazon.com/How-Repair-Pla...5302799&sr=1-3

[Joe L.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Greg, I'm up against the same thing with my '90. (We have the same style dash.)

I bought Kurt Lammons' book on how to repair plastics. He's quite thorough and informative on ABS, PVC, SMC, and the various bumper materials.

As a matter of fact, I'm going to call the guys at his company in a few minutes because I have delamination of the foam/vinyl interface from the ABS substrate.

If you've removed the pad from the dash structure, most likely there is no "ABS" or other identifying marks. I think those marks are on the side that the foam is bonded to. (Could be mistaken here but that's my best guess.)

I've actually purchased the last one in existence and expect that they'll be shipping it today. It also has a bit of delam at the leading edge, that is, the edge just under the windshield. At least none of the tabs on the new one are broken.

I'll post what I learn from Lammons and company.

Bruce-----


Yes, I think I was mistaken thinking that the substrate plastic was linear polypropylene or polyethylene. I think you're correct and it is acrylonitrile-butadiene-styrene (ABS) or polyvinylchoride (PVC). That's good news, too, since these are a LOT easier to bond and repair than linear polyethylene or polypropylene.

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Just got off the phone with Kurt Lammon. What a NICE guy!!

Anyway, I emailed him a couple of pictures that show the delamination.

He said that if he couldn't diagnose it from the pics, he'd be glad to take a look at my original and devise/advise a repair.

So...as soon as I hear back from him, I'll post the results and we'll go from there. There's HOPE !!! (Finally)

[John H.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

I think you're correct and it is alkyl-benzyl-sulfonate (ABS)

Joe -

Some still-active neurons from the "old days" coughed up "acrylonitrile butadiene styrene" as the composition of ABS plastic; is that the same or similar to the one you noted?

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

John, you've nailed the correct composition.

[Joe L.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Joe -

Some still-active neurons from the "old days" coughed up "acrylonitrile butadiene styrene" as the composition of ABS plastic; is that the same or similar to the one you noted?

John-----


No, I blew it on that one. ABS is an abbreviation for TWO different substances: one of these is acylonitrile-butadiene-styrene which is the plastic. The other is alkyl-benzene-sulfonate which is a detergent. From my working days, the alkyl-benzene-sulfonate was "drilled into my head" as the compound associated with the abbreviation ABS. So, I incorrectly "regurgitated" it in my previous post. I don't know how I did that since I know that alkyl-benzene-sulfonate is a detergent and not a plastic. In fact, when I typed it out something in the back of my head told me it's not right but I didn't take the time to check it.

I corrected it in the previous post.

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

John-----


No, I blew it on that one. ABS is an abbreviation for TWO different substances: one of these is acylonitrile-butadiene-styrene which is the plastic. The other is alkyl-benzene-sulfonate which is a detergent. From my working days, the alkyl-benzene-sulfonate was "drilled into my head" as the compound associated with the abbreviation ABS. So, I incorrectly "regurgitated" it in my previous post. I don't know how I did that since I know that alkyl-benzene-sulfonate is a detergent and not a plastic. In fact, when I typed it out something in the back of my head told me it's not right but I didn't take the time to check it.

You guys ought to come spend a few days with us in the airline. We've been making acronyms since Wilbur told Orville it would never fly and....we've never stopped.

[Bruce C.]

Repairing Dash Pad Plastic on a 96-update

Greg, here's the body of Kurt's email when I came in this morning:

Dear Bruce,

Thanks very much for your inquiry today and for buying my book!! I’ve looked at your photos and it looks like you’d be best served by using a slow-cure urethane two-part adhesive. My recommendation would be to use a product by 3M called Duramix 08214 universal adhesive. It’s a slow cure urethane that’ll allow you to pump in a bead around the edge, tape or clamp the gap shut, and cure. I think this would be your best bet.
3M bought Duramix a few years ago and I think they’re starting to phase the line out and direct people toward their Automix line. I think that most of the Automix line uses epoxy chemistry, which I don’t think would be as good as the urethane adhesive for this application. Call some of your local autobody supply stores and ask for the Duramix. Unfortunately, you’ll need a special dispensing gun to use the product...

Best wishes for a successful repair!
Thanks
Kurt

[Greg G.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Thanks Bruce! Excellent information here. Is Kurt recommending Duramix to fix the delamination of vinyl covered foam from the ABS substrate or is this his recommendation to repair broken ABS?

[Bruce C.]

Re: Need Advice on Repairing Dash Pad Plastic on a 96

Thanks Bruce! Excellent information here. Is Kurt recommending Duramix to fix the delamination of vinyl covered foam from the ABS substrate or is this his recommendation to repair broken ABS?

Greg, this recommendation is to re-bond the foam/vinyl to the substrate.

The repairs for abs components are in his book.

If you don't have a copy of it yet, I'll be glad to copy it at our bizhub (I LOVE that kind of talk) and email you the pdf. It will be in the morning, though, as the book is at the house.

I'm thinkin'...once Mike ships my new one, why don't I take some impressions from the intact/new tabs and send those to you.

You'll know what I mean when you see the book.

I strongly recommend getting Kurt's book just because it is so rich with how-to-repair info in addition to teaching you how to identify the material you want to repair.

The new pad, by the way, has some delam but nothing like my original.

Shoot me a pm with your phone # and we'll chat.