Factory "massaging" of front door edges??

[Gasasaur]

Ok, I've had three low mileage original square body's over the last several years, an '84, '86, and my most recent '87.

All three of these trucks are super nice with no signs of being in an accident, yet all three look like a novice curved the front edge of the doors (where they meet the front fender) to help make them fit. And this is on both doors. Interestingly enough, all three were built in Canada.

Anyway, I am anal and as nice as these trucks are, this has always bothered me. I went on eBay and zoomed in on this area in some of the pictures there, and sure enough, I see they have it too. I'm not saying they all have it, but I see it on a lot of them.

What is this all about? Have you guys noticed this?

[Warrens69GMC]

do you have pictures of what you are referring to?

[trixter99]

Every one of these trucks I have owened is like this it's so the door doesn't hit the fender when opening and closing.

[Danmcg]

Dang, now I got to go look...

[Gasasaur]

The pictures I took earlier don't show it too well, but I will try again later. My truck is black, so it looks pretty rough.

I can't believe they were doing this. But it has to be from GM, there is no other way to explain three trucks in a row that I've owned, plus the others I see that have the same thing.

My current truck was bought from the original owner who swears it's original paint and it only had 51k miles on it. My last truck wasn't the original owner, but it only had 49k on it and it had the original paint also.

Ok, it's time to wash the beast anyway. I will try for those pic's.

[TKCR]

Keith Seymore would be the person to ask. He worked at the plant.

[Gasasaur]

I really hope he responds to this. I'd love to hear it from someone that was there.

[TKCR]

Originally Posted by Gasasaur

I really hope he responds to this. I'd love to hear it from someone that was there.

I sent him a PM about this thread.

[jocko]

Originally Posted by Gasasaur

Ok, I've had three low mileage original square body's over the last several years, an '84, '86, and my most recent '87.

All three of these trucks are super nice with no signs of being in an accident, yet all three look like a novice curved the front edge of the doors (where they meet the front fender) to help make them fit. And this is on both doors. Interestingly enough, all three were built in Canada.

Anyway, I am anal and as nice as these trucks are, this has always bothered me. I went on eBay and zoomed in on this area in some of the pictures there, and sure enough, I see they have it too. I'm not saying they all have it, but I see it on a lot of them.

What is this all about? Have you guys noticed this?

I guess I gotta go look now too! Ha. I've only noticed aftermarket fenders not matching the bodyline at the very upper edge of the door/fender junction - but not the door fwd edge itself. I GOTTA go look! Ha. Interested.

[Keith Seymore]

Originally Posted by Gasasaur

Factory "massaging" of front door edges??

No.

The doors come in as raw metal and are run through the ELPO tank after being attached to the cab. There is no opportunity (or time) to do an extensive rework, as the cab shop was running around 70 jobs per hour in order to keep the final line fed at 60 jobs per hour (one completed truck every minute).

The tools used to make the doors (and other sheetmetal parts) wear out with use, causing the edges and feature lines to get more rounded. We made somewhere around 15 million square bodies. If we had kept going long enough all of the doors would have morphed into big round balls....

K

[Gasasaur]

Did you happen to know if the front edge of the door was a problem area imparticular? Any talk of it?

[TKCR]

Originally Posted by Gasasaur

Did you happen to know if the front edge of the door was a problem area imparticular? Any talk of it?

Well I can also say, that working in an auto manufacture plant myself, Keith is right about the time constraints on hand working or "massaging" an area on the vehicle. The vehicles are stamped, welded, assembled and then on to get dipped in a e-coat tank. From there, it's onto paint. And then out to assembly to get all the parts installed on the vehicle. All this is done on assembly lines that are constantly moving. Vehicle are produced on an average of a unit a minute. But to "massage" an area on that many vehicles, in a specific area, I would say it's impossible. It is more or likely just the way the metal was stamped for the door skin.

[Keith Seymore]

Originally Posted by Gasasaur

Did you happen to know if the front edge of the door was a problem area imparticular? Any talk of it?

Nope.

Bigger problem was getting the door(s) to fit in the cab. The cab was built up of several separate pieces, not a complete stamping like today's vehicles. Lots of variability in getting the door opening to come together and the door gaps to be even with respect to the cab.

The leading edge of the door was no problem as it interfaces with the rear of the fender, which has six degrees of freedom (that is, it can be shimmed up/down, in/out and adjusted fore/aft, depending on what is required).

Also - fenders were retooled for 1981, so the rear of the fender was a little "fresher" than the rest of the truck.

Lastly - squarebody assembly photos are available for viewing here, in case you have not seen them:
http://www.73-87.com/7387info/Assembly%20Line.htm



K

[Gasasaur]

Just to be clear, it's actually the door that we are talking about here. The front edge "drops off" like it was bent in for clearance, which I now understand would not have been possible due to time constraints.

I wonder if because these were trucks, they tried to get more mileage out of the dies because quality wasn't as important as it was on the cars.

But I'll reiterate, I believe there are a lot of doors out there with the front edge like this. Sounds like this was the first place the dies started failing to provide the original shape.

[jdl71]

Keith, were the fenders shimmed as the body was going down the line? Seems like that could tie things up if they spent too much time trying to get the gaps just right. Or maybe not, I guess after you've done a few hundred thousand of them maybe you can eyeball it and have a good idea of how many are needed and where, pretty quick.

[Keith Seymore]

Originally Posted by jdl71

Keith, were the fenders shimmed as the body was going down the line? Seems like that could tie things up if they spent too much time trying to get the gaps just right. Or maybe not, I guess after you've done a few hundred thousand of them maybe you can eyeball it and have a good idea of how many are needed and where, pretty quick.

What we used to do for fender shims is tape a packet together, like 3 shims, and we would run those all day whether the truck we were currently in front of us needed it or not.

Eventually the final repair supervisor would call back and say something encouraging, like "SEYMORE!! YOU IDIOT!! WTH ARE YOU THINKING?!?! ALL THESE FENDERS ARE RUNNING HIGH!! ARE YOU EVEN LOOKING AT THESE TRUCKS?!? TAKE A SHIM OUT BEFORE I COME BACK THERE AND SHOW YOU HOW TO DO THIS!!" I can just imagine the spittle flying into the phone mouthpiece.

So we would start running a new shim pack, like 2 shims, until he called again with his latest observation.

Basically it was to address "macro trends". You had about 45 seconds to complete the truck in front of you and move to the next one; that's not enough time to fit and re-fit each individual truck.

I should add that many of the repairs did not consist of removing the bolt or adding/deleting shims. Often the repair consisted of bending (like sticking a padded 4x4 into the door opening behind the fender, bending the dogleg portion of the fender out), twisting or hammering while the line was moving.

K

[D13]

Front clip is bolted on with a 'trend build' pack of shims. Primarily on the top. The bottom is then pushed or pulled up and down and fore / aft to 'fit' the fender to the door, primarily to get the curve to match the door.

If the fit was way off, say the fender hitting the pillar at the top and inboard of the door in the middle, the upper bolt could be loosened and a shim pulled out to drop the top and 'fatten' the fender at the door. If the gap was a serious 'A' or 'V' in the side vies shims could be added or subtracted front / back to get the fender rear edge more aligned to the door.

Every few days the shim pack was evaluated and changed if needed. On a certain wagon that we built in my plant, the shim pack was 1/8" different right to left. On another wagon the hood was over crowned compared to the fenders, a 2x4 along the center and a precisely tuned blow with a 2 lb dead blow would flatten the hood right to the fender.

Point of amusement, the shim pack in the front end is set with the same trend data. Every now and then you would get a shift in frame and the alignment rack would be swearing for a day until the new trend pack was installed - about 6 hours to know a change was needed, hour to make the change, then 6 hours until the new pack hit the end of the line. Meanwhile every vehicle has to be re-shimmed...

BTW if you ever buy an armored up RWD Cadillac Brougham out of the 80's. that's a 1/2 ton truck suspension under the front.

[Keith Seymore]

The fender-to-door gap was set using a little magnetic fixture which stuck to the door and had a little nylon tab of the desired thickness inserted into the gap. One fixture was stuck towards the top of the door (just below the A pillar) and one stuck to the bottom.

There were two guys per side working fender install, one at the front and one at the rear. They would take the fender off the overhead carrier, where it was presented upside down, already painted, emblems installed, trim installed and wheel liner installed. In one motion they would lift off the carrier, swing it toward the vehicle while flipping it upright and position it on the vehicle. The guy at the rear would jam it against the gap fixture and run the rearmost vertical bolt in; while he was doing that the guy in the front would start running in the nose bolts (to the radiator support, which was sitting loose on the chassis). The rear guy would open the door and run in the rearmost horizontal bolt and then hold the dogleg portion of the fender jammed against the gap fixture by wedging the aforementioned padded 4x4 between the tire and the wheel opening. The guy in the pit would run in the lower fender bolt.

Then - on to the next one. One per minute all day.

These are Pontiacs but the process is the same: you can see a snippet at the 2:25 mark
https://www.youtube.com/watch?v=02eULOTP6CA

K

[D13]

7 million hits on full size sedan door header dies. Then they were lightly 'refreshed'. And ran several more years. You can imagine the change in radiuses over time.

[TKCR]

A few videos of the manufacturing plants:

https://youtu.be/sWnT0RKvUSI

https://youtu.be/jBhe-6U2b5I

https://youtu.be/4bja_5Q0hZ8

[Keith Seymore]

Originally Posted by TKCR

A few videos of the manufacturing plants:

https://youtu.be/sWnT0RKvUSI

https://youtu.be/jBhe-6U2b5I

https://youtu.be/4bja_5Q0hZ8

The first and third videos are from Arlington, TX. I have launched product during model change in that plant (as well as nine other full size truck plants, and one passenger car plant).

The middle video is from Chevrolet Flint Assembly, where I started with GM almost 38 years ago.

K

[TKCR]

Originally Posted by Keith Seymore

The first and third videos are from Arlington, TX. I have launched product during model change in that plant (as well as nine other full size truck plants, and one passenger car plant).

The middle video is from Chevrolet Flint Assembly, where I started with GM almost 38 years ago.

K

That's cool!!