OD of paint buffing pads used on the C2 production line?

[Owen L.]

Now if anyone can answer Gary's original question ....

For those of us not in the know, why does it matter what size pad was used?

[Gary B.]

For those of us not in the know, why does it matter what size pad was used?

Owen,

In part, the pad diameter determines what could get buffed easily and what couldn’t. And some people want to use the same size pad that GM used when buffing their car. And some people just want to know for the sake of knowing.

Gary

[Mark F.]

FYI - Larry Galloway (NCRS Member) was THERE at St. Louis AND Ionia from August 1962 thru sometime in 1967 functioning in a QA/QC role...

He is very knowledgeable about and quite willing to discuss what went on...
He has written at least 2 books on the C2 process...buy them if you have a C2... Corvette 1963-1967 and Corvette C2: 1963 The Model Year that launched the Corvette into history!

The only text I can find about buffing is from John Hinckley's C2 Assembly Process Presentation (available in the Database of Restoration Documents [DoRD] Sticky Post), where he says:

Because the Corvette fiberglass body couldn’t withstand the required lacquer reflow temperature (35 minutes at 325°F) used on steel-bodied cars, final polishing was necessary to create the same exterior gloss level. Polishing compound was brush-applied and buffed with wool pads, only above the body side feature line, in the open area between the end of the Paint Shop and the beginning of the Hard Trim Line.

Some of the photos posted here appear to show that there may have been some level of buffing below, but near the belt-line...but that's speculation on my part...

[David H.]

[Mark Francis (30800) .. .. FYI - Larry Galloway (NCRS Member) was there at St. Louis AND Ionia from August 1962 thru sometime in 1967 functioning in a QA/QC role... ...

He has written at least 2 books on the C2 process...buy them if you have a C2...Corvette 1963-1967 and Corvette C2: 1963 The Model Year that launched the Corvette into history! ... [/QUOTE]


+1 Buy them even if you don't have a C2. Both are very informative books.

Restorers and Judges consider: Page 124 of "1963 The Model Year ..." on Production Difficulties.

660 Notice of Production Changes during 1963 or an average of about 3 per day.

All model years have production changes. John Hinckley's article on Assembly Manuals and Running Changes is a worthwhile read as well.

Dave

http://www.camaros.org/AIM.shtml

[Tim E.]

Hi Gary - I have a document in my library titled "CORVETTE-ST. LOUIS PAINT SHOP INFORMATION" authored by Harry Jones of the Michigan Chapter. Harry’s title was General Motor Assembly Division (GMAD) Senior Process and Production Engineer and one of his responsibilities was coordinating Corvette Body, Paint and Trim adhesives, sealants, bonding and paint materials, processes and equipment with the GMAD Corvette Assembly Plant.

Here is the section on buffing from his document:

POLISH AREA

• Since fiberglass body panels could not withstand specified lacquer topcoat final bake reflow temperature-35 minutes at 325F, polishing exterior surfaces was required to create same gloss level as would have been obtained if bodies could have passed through reflow oven.
• Operators used electric polish wheels and specified 17-inch diameter polish pads. Polish material applied with large paintbrush slopped onto panels. Very few vehicles were polished below body side accent line. Operators did not like to bend over to reach these areas. Polishing was performed in open area between Paint and Trim Shops boundaries.

The size of the sanding disk used to smooth the body seams was 8". Perhaps that is where you're remembering the 8" from.

Tim

[Mark F.]

Hi Tim,
Thanks very much for that information !

Are you able to share Harry’s document ?

The reason I ask is I have done lots of research and combining various source materials and information on the C2 Corvette Assembly process…Some of it is probably also applicable to C1s and C3s, but almost all that I have seen so far has been C2-specific. My goal is to submit something for a Restorer Article (don’t know what form that will be yet [Tables; Flowcharts; Text; combinations of all of those ?])

I’d love to have an opportunity to review and add Harry’s work to the sources listed below that I have studied so far:
Sources:

1. John Hinckley 2011 National Convention Presentations
2. Larry Galloway - Two Books he wrote on C2s: Corvette 1963-1967 and Corvette C2: 1963
3. John Hinckley Articles he wrote from 6/2005 thru 1/2007 in Corvette Enthusiast Magazine
4. Noland Adams Corvette Restoration & Technical Guide Vol 2; pages 16-33
5. Pete Licastro Birthplace of Legends 1993
6. GM Heritage Center Collection DN1092B_0003

By the way (and you probably already know this), John Hinckley's C2 Assembly Process Presentation (available in the Database of Restoration Documents [DoRD] Sticky Post), acknowledges Harry’s contributions to John’s presentation as follows:
Note: Special thanks are due to fellow Michigan Chapter member Harry Jones for much of the process detail for the Paint Shop operations; Harry “was there” at St. Louis during the midyear era when he was with the Chevrolet Central Office Paint Standards Department, and his extensive process notes and recollections of the St. Louis Paint Shop operations and facilities made much of this section possible.

[Gary B.]

Hi Gary - I have a document in my library titled "CORVETTE-ST. LOUIS PAINT SHOP INFORMATION" authored by Harry Jones of the Michigan Chapter. Harry’s title was General Motor Assembly Division (GMAD) Senior Process and Production Engineer and one of his responsibilities was coordinating Corvette Body, Paint and Trim adhesives, sealants, bonding and paint materials, processes and equipment with the GMAD Corvette Assembly Plant.

Here is the section on buffing from his document:

POLISH AREA

• Since fiberglass body panels could not withstand specified lacquer topcoat final bake reflow temperature-35 minutes at 325F, polishing exterior surfaces was required to create same gloss level as would have been obtained if bodies could have passed through reflow oven.
• Operators used electric polish wheels and specified 17-inch diameter polish pads. Polish material applied with large paintbrush slopped onto panels. Very few vehicles were polished below body side accent line. Operators did not like to bend over to reach these areas. Polishing was performed in open area between Paint and Trim Shops boundaries.

The size of the sanding disk used to smooth the body seams was 8". Perhaps that is where you're remembering the 8" from.

Tim

Tim,

That Harry Jones document a great find. Unfortunately, the 17” size presents a new problem. A 17” OD pad would be larger in diameter than the metal part of the rear wheel in the photo Jack posted. And my estimate of pad ID using the person’s glasses as a scale would mean the temple-to-temple width of the glasses would have to be close to 8” in order for the buffing aid to be 17”. But not eyeglass have an 8” temple-to-temple width. So, the 17” size conflicts with the several photos we’ve seen of workers with buffing machines/pads. Now you could revisit the “posed” photo argument in which case you’d have to conclude the three workers were posed with the wrong size buffing pads. So, I’m now left more confused than I was before. (Except the 8” sanding disk OD might indeed be what I was remembering.)

Is the Harry Jones document publicly available online somewhere?

Gary

[Tim E.]

Mark - Attached is Harry's article. There is a wealth of information that you will find useful. Congratulations on putting together an article for The Restorer.

I'm going to compare your list of reference material with articles & research in my library that I used to develop a judging school presentation on the C1 thru C6 Corvette Paint Evolution, Process, and Judging. I put it together first for the Rocky Mountain Chapter and most recently for the Lone Star Regional in Frisco, TX. In addition to your material, I may have a couple more that you're welcome to.

Tim

CORVETTE-ST. LOUIS PAINT SHOP INFORMATION article by Harry Jones.docx

[Joseph S.]

Tim,

That Harry Jones document a great find. Unfortunately, the 17” size presents a new problem. A 17” OD pad would be larger in diameter than the metal part of the rear wheel in the photo Jack posted. And my estimate of pad ID using the person’s glasses as a scale would mean the temple-to-temple width of the glasses would have to be close to 8” in order for the buffing aid to be 17”. But not eyeglass have an 8” temple-to-temple width. So, the 17” size conflicts with the several photos we’ve seen of workers with buffing machines/pads. Now you could revisit the “posed” photo argument in which case you’d have to conclude the three workers were posed with the wrong size buffing pads. So, I’m now left more confused than I was before. (Except the 8” sanding disk OD might indeed be what I was remembering.)

Is the Harry Jones document publicly available online somewhere?

Gary

Gary, The 17 is probably a typo. An old time full size buffing pad is a 7" base. Depending on if they are heavy cut or finish cut they can vary from about 8" to 10" due to the length of the fibers on it.

Sorry for delay answering this I just read it.

Regards, Joe

[Gary B.]

Joe,

Thanks for chiming in. The typo theory seems like the most likely explanation to me.

Gary

[Mark F.]

Mark - Attached is Harry's article. There is a wealth of information that you will find useful. Congratulations on putting together an article for The Restorer.

I'm going to compare your list of reference material with articles & research in my library that I used to develop a judging school presentation on the C1 thru C6 Corvette Paint Evolution, Process, and Judging. I put it together first for the Rocky Mountain Chapter and most recently for the Lone Star Regional in Frisco, TX. In addition to your material, I may have a couple more that you're welcome to. Tim [ATTACH]n1575892[/ATTACH]

Hi Tim,

Thank you so much...lots of detail there that I'll have to study...
I'll have to compare what he says was done for C1s vs C2s; but I'm betting there's not much of a difference...
Again, I appreciate you sharing this with me (us)

Here are a few lists of Corvette Enthusiast Articles John Hinckley wrote:
There were two assembly-relevant articles before John began his midyear series of articles:

1. "Engine Dress At St. Louis-Corvette" on pages 44-47 in the June '05 issue
2. "The Frame Game" on pages 52-56 in the August '05 issue

Then there were at least six in his midyear assembly series:

1. AOS Bodies - "The "Other" Corvette body Builder" on pages 64-65 in the June '06 issue
2. Body Shop - "Building a Legend" on pages 36-45 in the August '06 issue
3. Paint Shop - "The Color Comes Through" on pages 36-40 in the October '06 issue
4. Hard Trim Line - "Getting Trimmed Out" on pages 48-55 in the November '06 issue
5. Chassis FUDL/EDL/CL - "An Under-Body Experience" on pages 42-48 in the December '06 issue
6. Body Drop thru Final Rolloff - "A Car at Last" on pages 80-84 in the January '07 issue

Other articles of Interest in Corvette Enthusiast:

1. May '05 Small Block Assembly Overview
2. Oct '05 The Plastic Fantastic - Evolution of Corvette Fiberglass
3. Nov '05 By the Book - Understanding Your AIM
4. Jul '06 Goin' Straight 1963-1981 Wheel Alignment
5. Feb '07 Casting Call - Foundry Operations

[David H.]

... Here are a few lists of Corvette Enthusiast Articles John Hinckley wrote...

All those John Hinckley articles available at Camaros.org - link below:

http://www.camaros.org/library.shtml

Dave

[Tim E.]

Here's a photo of my trusty old wool buffing pad. As Joe points out, the backing pad on this one is 6" with a pad diameter of 9".

At the judging school I ran, I took this buffing pad, a sample of the paste compound, and also samples of 220, 280, & 320 grit sandpaper to pass around. Students were able to feel the difference between the course grits used on C1 - C3 Corvettes back in the day versus the foam pads, polishing compounds, and 3000 grit sandpapers available today! Very eye opening!

Tim

WoolBuffingPad.jpg

[Gary B.]

To add to the photos already posted of workers polishing C2s, here’s a photo from Noland Adam’s book showing one worker (probably standing on a stool) polishing the roof of a ‘63 coupe on the driver’s side and you can just see the polishing pad of a 2nd worker on the passenger’s side. You can see how flexible the polishing pad is on the passenger’s side.

Clearly the pad is not 17” in diameter.

Gary

[Mark F.]

To add to the photos already posted of workers polishing C2s, here’s a photo from Noland Adam’s book showing one worker (probably standing on a stool) polishing the roof of a ‘63 coupe on the driver’s side and you can just see the polishing pad of a 2nd worker on the passenger’s side. You can see how flexible the polishing pad is on the passenger’s side. Clearly the pad is not 17” in diameter. Gary

Hi Gary,

Yeah, he could be standing on a platform of some type...

When I was at Ford, I spent a lot of time in paint booths collecting air samples for airborne pigments and solvents to evaluate potential employee breathing zone exposures to various chemical compounds. All of my experience was on metal-bodied vehicles, so the paint processes then ('77 to '81) did not require buffing that I ever saw...

For taller vehicles (mostly trucks and vans - not Mustang IIs and lower cars like that), pneumatic steel-grated platforms raised the employee so no struggling was necessary to paint the roof...or maybe in this case buff the roof. (keep in mind they are all on conveyor trucks which raise the height of the body as shown in Noland's photo).

The platforms were actuated by a large button valve, which was recessed into the open steel grate platform floors so it couldn't accidentally be engaged unexpectedly. The employee would stick his big toe down in that recess pressing on the valve button, which would then elevate the platform (quite rapidly I might add...)

Once done painting, the button valve would be engaged again lowering the platform to booth-floor level so body sides; hoods; rear decks; rockers could all get painted...

and as someone has said elsewhere, most of the runs and poor coverage I saw were well below the belt line where it was hard to reach and uncomfortable while trying to hold and trigger large Ransburg electrostatic fogging paint guns...