Repairing 70 Interior Quarter Trim

[Bill L.]

I purchased a repro set only to find they do not fit. I have the set of originals that bubba went to work on. All the nuts on the back side were popped out and small holes were drilled out. The one side also has a 2-3" crack at the bottom behind the seat when installed. I think the crack is repairable. I am not so sure of the rest.

Can they be effectively repaired. If so, I would love some suggestions. I am really hoping to save these in that mine is one of those rare 70 verts with shoulder harness so these panels are really hard to find in any condition. Albeit they are the same I think through early 74.

Thanks as always!



Bill

[Kevin G.]

Re: Repairing 70 Interior Quarter Trim

Bill,

Recently I had the same problem with nuts/anchors on my 72, no cracks. I found some brass sleeves at the hardware store for the correct size screw. Redrilled the holes and used JB Weld to attach them, worked perfect. If the holes go all the way threw, some paint might be needed. As for the crack, perhaps glue with a piece of thin backing to reinforce it?

Good luck,
Kevin

[Chuck S.]

Re: Repairing 70 Interior Quarter Trim

One of the problems with making a perfect repair on the quarter trim is that they are vinyl covered fiberglass. Kevin has an excellent suggestion for the embedded nuts, but whatever you do for the crack, you will still have a crack in the vinyl when you're done. Your best hope is to conceal the vinyl crack as much as possible.

I would use resin and fiberglass cloth to make the crack repair on the backside of the trim. Mask the trim carefully to avoid fingerprinting the resin all over the vinyl covering, and prevent leakage through the crack. Let it cure and see what you have...a little vinyl spray dye may help, but you may be better off doing further.

[Robert M.]

Re: Repairing 70 Interior Quarter Trim

One of the problems with making a perfect repair on the quarter trim is that they are vinyl covered fiberglass.........

They are?
I thought the 68 and 69's were vinyl covered.
I've never looked at the 1970 and later cars, just assumed they were not vinyl covered. My own 1970 was a basket case rescue, so it may or may not of had the original quarter trim when I got my hands on it.

I always thought no vinyl, based on what the vendor catalogues showed. I should probably look again.

[Bill L.]

Re: Repairing 70 Interior Quarter Trim

Hi Chuck,

The originals are not covered. I wish they were and I would have AL K recover them to look as good as new.

They are molded fiberglass I think.

I am thinking about trying to repair them similar to the way you fix the small cracks in body panels.

My next question is if I make a textured mold, how can I keep the fiberglass from sticking to the mold?

I also found a repair kit that includes the small nuts imbedded in the panels.

Keep the suggestions coming!


Thanks, Bill

[Terry M.]

Re: Repairing 70 Interior Quarter Trim

I don't think the 1970 quarter panels are vinyl covered -- at least my bight blue ones are not. On the other hand, I'm pretty sure 1968s are. Where the change is ???? Glad I don't judge interiors.

[Chuck S.]

Re: Repairing 70 Interior Quarter Trim

...The originals are not covered. I wish they were and I would have AL K recover them to look as good as new.

They are molded fiberglass I think...

Better take a closer look...I don't know about the convertible with shoulder belt quarter trim panels, but the coupe panels are DEFINITELY vinyl covered. I'm sitting here looking at one of my originals right now...it's match molded black fiberglass with bright blue vinyl wrapping around the edge to the back side about 1/4"-1/2" all around. Most of the unpadded interior trim is contructed like this; the only piece I can think of that is not is the rear console with the PB handle, but then my rear console did appear to have been replaced somewhere along the line...the original rear console may also have been vinyl covered.

I doubt Al could do any better covering these than you can. Just because something is vinyl covered does not mean it has fluffy padding under the vinyl...the grained vinyl is bonded directly onto the fiberglass with adhesive and possibly heat. Perhaps vinyl CLAD is the better terminology to describe the construction.

Edit: Incidentally, the quarter panel I examined is also definitely original...it's ink stamped on the back 195 0 1, or July 14, 1970, first shift. (my car's build date is G30 or July 30).

[Warren F.]

Re: Repairing 70 Interior Quarter Trim

I agree with Chuck. Both of my '71's, which are complete original interiors, one black, one red, have a thin covering that you can see or feel that wraps around the edge about a quarter inch or more. It has a texture that at close inspection appears to be a molded plastic appearance. Now the shoulder belt housing is a hard plastic that is attached to the quarter pieces.

[Reba W.]

Re: Repairing 70 Interior Quarter Trim

The judging guide lists the vinyl covering for the 1968-69s, which we are fairly certain is correct. However, in judging I have occasionally found these on later cars, even one 1972 if I remember correctly. Just more research to do for updating guides.

[Robert M.]

Re: Repairing 70 Interior Quarter Trim

I just checked on 2 LH rear quarter panels that I have, for a convertible with shoulder belt cut outs. The part number on the back side of each shows 3974051 LH.

My 1970 AIM calls out 3974051 LH as the part used for 1970 Convertibles.

Neither part is vinyl covered, nor shows any evidence of ever being covered. FWIW.

[Chuck S.]

Re: Repairing 70 Interior Quarter Trim

...My 1970 AIM calls out 3974051 LH as the part used for 1970 Convertibles.

Neither part is vinyl covered, nor shows any evidence of ever being covered...

Yep...it appears both our parts are original...mine vinyl clad and yours not.

Edit: I might have just demonstrated how to make an error in calling a part original: If a part is dated appropriately for the car, it's VERY likely to be original to the car; if it has the original part number molded into the surface, that may indicate that it is an original part, OR, that it is just a GM part that may be original or may be a service replacement.

Like the example I gave of my rear console being different from the rest of the interior trim, broken parts might have been replaced with the contemporary GM offering, which may or may not be the same configuration, and may or may not have had the same part number. I suspect my rear console was a GM part because it was replaced too early for a reproduction to be relevant...it was molded out of natural colored fiberglass with a grained surface and painted the bright blue finish, which was out of character for the rest of the trim. It's possible that all service replacement trim was provided in that configuration to eliminate having to maintain color inventory.

As I said in my earlier post, I am unfamiliar with convertibles either with or without shoulder belts...sorry for the misdirection, but the vinyl made a special problem for me. It was reasonable to assume (until proven otherwise) that GM would make the interior trim in similar construction for both coupes and convertibles.

The reason my attention was drawn to the details of the vinyl covering on my coupe quarters is that the vinyl skin around the bottom hole of one of the originals was broken and cracked out by someone partially removing the embedded screw, then smacking the trim, which was coming up with the screw head, back into position. That essentially made the part ugly and unrepairable, and a replacement was necessary.

For a low volume part, like a unique part for an option, I can understand how GM might accept some corner cutting to reduce part cost because of low volume. They might even have experimented with reducing future models' trim cost by trying another construction technique on low volume unique parts. The alternate method was to simply mold the vinyl graining into the part surface and paint the color finish to eliminate the additional cladding steps and the expense of the vinyl material. Its still commonly used today, except the painting steps have also been eliminated by using colored resin to mold the color directly into the parts.

It's interesting that the AIM illustrates ONLY the convertible quarter trim panel with the shoulder belt opening...PN 3974051-2. Was any other quarter trim used on convertibles? No other part number is listed. Or, is the same part number molded on both parts, with a suffix used only on packaging or shipping documents...But we all know about reading too much into AIM drawings. What I'm curious about now is, now that we know some coupe quarter trim panels were vinyl clad, were ALL the coupe quarter trim panels after 69 vinyl clad or only some?...and, if so, how did that happen?

In this discussion, we have uncovered a variation that is not well known or covered in the TIM&JG, and as Reba implied, refinement of our general knowledge and references is always a good thing.

[Robert M.]

Re: Repairing 70 Interior Quarter Trim

It's interesting that the AIM illustrates ONLY the convertible quarter trim panel with the shoulder belt opening...PN 3974051-2. Was any other quarter trim used on convertibles?

Chuck,
I thought once I had seen a variation of the convertible quarter trim panel without cut outs. I searched on ebay and found these http://cgi.ebay.com/ebaymotors/70-71...spagenameZWDVW

Notice the description says they are 3974051 & 52, same as what I have, but very different looking, no cut out, and they seem to abruptly stop in the rearward direction. So it tells me the the same numbers were used for a few variations of the same part.

[Chuck S.]

Re: Repairing 70 Interior Quarter Trim

Chuck,
I thought once I had seen a variation of the convertible quarter trim panel without cut outs. I searched on ebay and found these http://cgi.ebay.com/ebaymotors/70-71...spagenameZWDVW

Notice the description says they are 3974051 & 52, same as what I have, but very different looking, no cut out, and they seem to abruptly stop in the rearward direction. So it tells me the the same numbers were used for a few variations of the same part.

Yeah, I misunderstood the "-2", it's actually not a suffix, it's the end digit of the RH part number, which is typical.

It's not unusual for them to have used the same part numbers, even for wholesale changes in part configuration in later iterations of service replacement parts...that's why we have so much trouble with parts that are sold as "NOS" parts that look nothing like the ones that came on the car.

It is, however, a little unusual for uniquely different parts concurrently in production to have the same part numbers. There must be more to this; maybe Joe will help us understand how this could happen. One thought that previously ran through my head when I saw the AIM illustration was that maybe they only made one quarter trim (for convertibles), and had to modify the panel for the standard cars on the line, just as the kick panels were modified for AC cars, but that would mean a LOT of additional work, waste, and chance for defects...doesn't make sense.

[Dennis D.]

Re: Repairing 70 Interior Quarter Trim

Chuck,
I thought once I had seen a variation of the convertible quarter trim panel without cut outs. I searched on ebay and found these http://cgi.ebay.com/ebaymotors/70-71...spagenameZWDVW

Notice the description says they are 3974051 & 52, same as what I have, but very different looking, no cut out, and they seem to abruptly stop in the rearward direction. So it tells me the the same numbers were used for a few variations of the same part.

May get corrected here, but I haven't seen convert 1/4 trim vinyl covered. Didn't think they were for 70
. As far as those ebay pics, I'd say someone modified those by cutting the last 4 or 5 inches off the end after the 90 degree bend. That would be where the cutout are. Happens to be a common area for breakage.

BTW... venders do sell aftermarket pieces with or without the cutouts.

[Chuck S.]

Re: Repairing 70 Interior Quarter Trim

May get corrected here, but I haven't seen convert 1/4 trim vinyl covered. Didn't think they were for 70
. As far as those ebay pics, I'd say someone modified those by cutting the last 4 or 5 inches off the end after the 90 degree bend. That would be where the cutout are. Happens to be a common area for breakage.

BTW... venders do sell aftermarket pieces with or without the cutouts.

Not much chance of you getting corrected by current posters, Dennis...only Warren and I have said any quarter trim panels were vinyl covered, and both of us have coupes. Because of Robert's input, I admitted earlier that it's possible quarter trim panels for convertibles, or even other 70-72 coupes may not be vinyl covered.

What I'm thinking now is that there was only ONE PAIR of quarter trim panels (sans vinyl cladding) for convertibles since there is only one pair of unique part numbers mentioned in the AIM. I'm thinking the guys on the assembly line must have had to "modify" the shoulder belt style convertible trim panels to fit the convertibles without the shoulder belt option (Band saw, special jig, one straight cut, do a week's supply at one sawing)...but that theory is sure not confirmed by anything in the AIM.

Besides illustrating only the shoulder belt style trim panel, and only one set of part numbers for same, the AIM shows NOTHING about any such modification. For myself, I will continue to believe this factory modification occurred until someone can explain why there is only one set of part numbers, or says that they have a smooth "as-molded" parting line on fore-shortened standard convertible trim panels.