When did the switch from lead to plastic happen ? I know on my '68 Cutlass 'vert the rear filler panel (base of rear roof)-top_of_quarter-trunk seams were leaded. And, I've heard that Oldsmobile used lead longer than most other mfgrs.

There's a '70 'vert in the same shop as mine that has plastic but has had some previous body work. The car owner says it should be plastic, but the shop owner says lead.

What's correct for a '70 vert ? When did they quit using lead ?

 

Can't tell you when but some time late 70's started switching from what I can tell, don't remember seeing past 1980 or maybe early 80's

I have seen the rear deck panel seam area done w/ plastic & they seem to crack w/ regularity. If you want to keep things the way they were originally done, leave or replace the lead.

I have found best insurance is to weld the deck panel seam solid to the quarter panel and then use plastic to either cover the seam or cut a faux seam into it. Haven't seen any failures on "A" or "F" bodies using this method. Don't know if there is some ramification to this but I haven't seen any.

Lead went away for safety reasons combined w/ the demand for a skilled person to work w/ it. Tools, torches & technique replaced by a little blob of crap w/ a string of paste & stir it together, voila - bodyman in a can. Still takes skill to finish it well but plastic is so much easier to work with & has to be much cheaper too. Probably only a health hazard if you eat it, snort it or breathe too much dust.

 

Thanks, bccan.
Ya, I knew it went away due to EPA regs & cost...

Did 1970 'verts have a visible seam in the deck panel ?

My '68 'vert does (did) not . It was solid smooth finished lead.

I was just trying to help settle a dispute between the body guy & the car owner. Owner says factory was plastic...Body guy says lead. Car is a Lansing built '70 vert.

 

My Vista Cruiser had lead filled seams and transitions and they used factory plastic filler to smooth some areas. It's most prevalent around the "C" pillar and roof panel areas. The plastic filler is a tan color and hard as a rock.

I used lead when I did the bodywork on mine, easier and faster than bondo IMO and does a 100% better job, no cracking or pinholes and when it's finished it's finished. It works like smooth peanut butter if you do it right, takes a lot of flame control or it just turns to liquid and you sure don't want to warp the sheet metal. You need to develop a touch, some guys just can't do it no matter how hard they try.
They make bars that have no lead in them now for lead work, tinning butter with acid and solder so you don't have to use tinner's acid then tin it with solder so the lead will stick like the old days. They sell all the stuff at Eastwood, get a kit and play with it until you get good, sort of fun actually. I worked with Bones the plumber 30 years ago and had to pound in oakum in joints with special chisels and then lead in black cast sewer stacks, hasn't killed me yet. You just use common sense, don't eat it or breathe it, keep it off your skin.
It's great for filling trim holes, use that metal tape behind the holes and go nuts, fill the holes with bondo and you'll get a bunch of little surprises after it shrinks.

 

Indy - I think the 68-72 verts are all smooth. One of those details I just can't remember for sure. We always just put em back the way they were when car comes in unless it is evidently messed with.

I think 4 doors were smooth & coupes (Supreme & "fastback") have visible seam.

That is IIRC.

BV - I'm kinda thinking the lead work was probably done @ Fisher Plant for the seams & maybe the plastic filler done @ assy plant for imperfections. Don't really know, just seems reasonable. That old filler is rock hard! Both the lead & that filler certainly proved to be good stuff - generally not a problem on these old cars if it was never messed with.

 

Thanks guys...
The '70 vert in question was taken down to the shell & soda blasted. One side is obviously wrong as it has about 1/4"+ thick coat of tan plastic the size of a dinner plate in the filler plate/qtr seam area. The other side has some tan, with a little very dark gray plastic (not lead) below it. All of the plastic is granite hard.

The owner has had the car since ~ 1972. It did have rather extensive qtr panel work done in the 70's as it was wrecked. I suspect the repairs introduced the plastic we're seeing.

Again...I only asked because the shop guy asked me (He apparently thinks I know something about these cars ) about Oldsmobiles & lead since mine had nice leaded seams....

Thanks again!

 

Sometime around late 60s. My 69 Toronado (12C car) had lead on one side of the roof-to-quarter seam and plastic on the other. Vinyl roof had never been off before then and the other seams on the LH quarter were all leaded. I talked with a guy from Fisher Body at a National Meet years ago who was working at that time and he mentioned they were doing some plastic filler testing about that time, though he thought it was more on A and B body cars than E-cars.

At any rate a vinyl top job was not metal finished as well as a painted roof car would have been.

I had a 73 Delta ragtop, Lansing car, that the quarter-to-tulip panel seams were leaded and finished smooth. A friend had a 73 Linden-built car that had clearly visible seam lines.

 

The BOP plant in Framingham used lead for seams when I was there from '72-74.

NASTY process!!!!!