435 sequential vin engine pads-comments?

[Michael H.]

Re: 435 sequential vin engine pads-comments?

I can see parts being somewhat random but I assumed that the cars went down the line in sequence. It would be a nightmare for the guy stamping engines/trannys

Kenneth,

I think you're right. I don't think the bodies had a specific VIN until after the body was built and painted but before it went on to the hard trim line. Once it was on the hard trim line, it would be locked in sequence.
Prior to the VIN plate, the body/car didn't have a VIN assigned. It was built using the job number.

[Kenneth B.]

Re: 435 sequential vin engine pads-comments?

Kenneth,

I think you're right. I don't think the bodies had a specific VIN until after the body was built and painted but before it went on to the hard trim line. Once it was on the hard trim line, it would be locked in sequence.
Prior to the VIN plate, the body/car didn't have a VIN assigned. It was built using the job number.

MIKE
Thanks That was my understanding also. That is why job #'s had nothing to do with SN. Job #'S didn't have to follow in sequance but vin #'S did.

[Michael J.]

Re: 435 sequential vin engine pads-comments?

You guys may be right, but I know the picture I have of my car coming off the end of line is not sequential with the ones behind it, and considering all the controlled chaos on an assembly line and the rush to push cars out the door and the pressure for QC, I just find it unlikely all the cars rolled off the line in neat sequential VIN order day in and day out, but maybe John Hinckley knows what happened in the old days and how different it is than today?

[Michael H.]

Re: 435 sequential vin engine pads-comments?

You guys may be right, but I know the picture I have of my car coming off the end of line is not sequential with the ones behind it, and considering all the controlled chaos on an assembly line and the rush to push cars out the door and the pressure for QC, I just find it unlikely all the cars rolled off the line in neat sequential VIN order day in and day out, but maybe John Hinckley knows what happened in the old days and how different it is than today?

Michael,

Prior to the final paint operation and VIN install, the bodies were on body trucks with wheels which allowed the bodies to be mixed randomly as they went through the many stages of body build and paint. It wasn't a continuous line at that point.

However, once the body came out of the last paint bake/reflow oven, the body/truck was set on a conveyor that wound all around the north section of the plant. It would not be (easily) possible for it to become out of sequence.

You have a picture of your car coming off the line at St Louis??

[Michael J.]

Re: 435 sequential vin engine pads-comments?

Michael,


You have a picture of your car coming off the line at St Louis??

That I don't have, just the Bowling Green car, that is why I was asking about what might have changed between the two plants to make the BG cars not coming out in VIN sequence.

[Michael J.]

Re: 435 sequential vin engine pads-comments?

John, do you know if all the cars came off the assembly line in St. Louis in strict VIN sequence? Thanks.

[Michael H.]

Re: 435 sequential vin engine pads-comments?

That I don't have, just the Bowling Green car, that is why I was asking about what might have changed between the two plants to make the BG cars not coming out in VIN sequence.

I don't know when the system changed but I think it did at some time during C3 production. I think later C3 cars going through the St Louis plant included the VIN number on the build sheets so that would say the VIN WAS known throughout the build.
I have the original/real build sheet for the last St Louis Corvette and I'm pretty sure the VIN is on it.

[William C.]

Re: 435 sequential vin engine pads-comments?

VIN had to be known as the Chassis frame and engine were sequenced to the correct body. Once married, inspections might drive some cars into repair where they would be out of sequence coming off the final line, as they were not resequenced after repair (which might take minutes or hours, depending on work required and repair bay volume), so a car coming off the final line out of sequence would not be at all unusual. At startup, many of the Plants I worked with might work a weekend shift just for the repair area if the repair bays backed up during the week. A a lot depended on the nature of the repair and the location where the problem was identified.

[Michael H.]

Re: 435 sequential vin engine pads-comments?

VIN had to be known as the Chassis frame and engine were sequenced to the correct body. Once married, inspections might drive some cars into repair where they would be out of sequence coming off the final line, as they were not resequenced after repair (which might take minutes or hours, depending on work required and repair bay volume), so a car coming off the final line out of sequence would not be at all unusual. At startup, many of the Plants I worked with might work a weekend shift just for the repair area if the repair bays backed up during the week. A a lot depended on the nature of the repair and the location where the problem was identified.

Bill,

Because the chassis and engine weren't on line for several hours after the trim/VIN tags were attached, it would not be necessary to know the VIN well before the chassis was assembled.
The bare frame was probably still sitting in the middle of a stack of frames when the VIN was attached to the body. The complete chassis only required about two hours to completely assemble.

[Michael J.]

Re: 435 sequential vin engine pads-comments?

VIN had to be known as the Chassis frame and engine were sequenced to the correct body. Once married, inspections might drive some cars into repair where they would be out of sequence coming off the final line, as they were not resequenced after repair (which might take minutes or hours, depending on work required and repair bay volume), so a car coming off the final line out of sequence would not be at all unusual. At startup, many of the Plants I worked with might work a weekend shift just for the repair area if the repair bays backed up during the week. A a lot depended on the nature of the repair and the location where the problem was identified.

That's exactly the reasoning the BG plant manager gave for cars being produced that were not sequential in VIN numbers. The QC process took precedent he said, so cars coming off the line as sequential VINs was not that common, according to him. The question is, was QC or process rigidity at the St. Louis plant that much different than BG, such that they maintained a strict VIN sequencing all through the line after VIN attachment so that the cars were produced sequentially by VIN.

[William C.]

Re: 435 sequential vin engine pads-comments?

Still have to be matched to the line, and keyed together. My point was to the end of the final line being non-sequential due to repair issues, not a mismatch between chassis/body.

[John H.]

Re: 435 sequential vin engine pads-comments?

John, do you know if all the cars came off the assembly line in St. Louis in strict VIN sequence? Thanks.

Michael -

During the midyear era, they came off the Final Line (with no interior in them) for Roll-Test, Toe-In, Water Test, etc. in VIN sequence, but by the time they got through subsequent Water Test Repair, Mechanical Repair, and Final Paint Repair, they entered the Final Trim Line (where the interior was installed, followed by the Shipping Gate) not necessarily in VIN sequence. The VIN was assigned (and the VIN plate was affixed) at the first operation on the Hard Trim Line (right after the end of the Paint Shop), and the unit was "locked in sequence" from that point all the way to the end of the Final Line.

[Michael H.]

Re: 435 sequential vin engine pads-comments?

Michael -

During the midyear era, they came off the Final Line (with no interior in them) for Roll-Test, Toe-In, Water Test, etc. in VIN sequence, but by the time they got through subsequent Water Test Repair, Mechanical Repair, and Final Paint Repair, they entered the Final Trim Line (where the interior was installed, followed by the Shipping Gate) not necessarily in VIN sequence. The VIN was assigned (and the VIN plate was affixed) at the first operation on the Hard Trim Line (right after the end of the Paint Shop), and the unit was "locked in sequence" from that point all the way to the end of the Final Line.

Thanks John. Michael Johnson wasn't buying my story. I was hoping you would get involved in this.

One of the reasons many people get confused on this is likely the fact that the line that includes body drop but not much of the rest of the build is because the line was called the "Final Line". As you mention, there was still a lot of car to assemble after it rolled off the end of the final line. I don't know why it was called that.

After final line, the worker had to toss in a jump seat (worn out temporary seat) to drive the car off the end of that line because most of the soft interior wasn't installed at that point. That would make sense. Why bring a unit to water test with a complete interior?

[John H.]

Re: 435 sequential vin engine pads-comments?

That's exactly the reasoning the BG plant manager gave for cars being produced that were not sequential in VIN numbers. The QC process took precedent he said, so cars coming off the line as sequential VINs was not that common, according to him. The question is, was QC or process rigidity at the St. Louis plant that much different than BG, such that they maintained a strict VIN sequencing all through the line after VIN attachment so that the cars were produced sequentially by VIN.

Michael -

As I noted in another post tonight, there's some confusion about "Lines" at St. Louis. The units were in absolute VIN sequence from the beginning of the Hard Trim Line (right after the end of the Paint Shop, where the VIN was assigned and the VIN plate was installed) until the end of the Final Line, where the car was driveable, but had no interior in it. After Roll-Test, Toe-in, Water Test & Repair, Mechanical Repair, and Final Paint Repair, the car went on the Final Trim Line, where it got the interior installed, Final Inspection, and Shipping, and at that point weren't necessarily in VIN sequence any more due to all the off-line operations between the Final Line and the Final Trim Line.

Steel-body car Chevrolet assembly plants didn't have "Soft Trim After Final" - when the car came off the Final Line, it was fully-assembled.

[Michael J.]

Re: 435 sequential vin engine pads-comments?

Thanks, that's what I had also been told, that at the end of the ENTIRE assembly process (whatever you want to call it), they were not rolling out in VIN sequence, just like they weren't in BG either, that's why the picture of my car and the plant manager's comments (from BG) were correct. Not being a former plant employee, I don't know the jargon, sorry. My original comment was that it was naive to think three big block '67 L71s roiled off the line in VIN sequence order, I still think so.