72 headlamp shields screws

[Edward J.]

Another, question reguarding JM fastners correct or not, my 72 coupe has 6 black phosphate cross recessed round head phillips head screws without built in washers, as the JM says with capitive washers, I have looked at a few 72's and have been without the washers,

Has anyone noted that there may be a difference between the 70-72 cars? I know thats this is a small detail, but, Im in the process of correcting the last details on my car for spring top flite judging.

This car was a well preserved 72 when I brought it, it was just a one repaint car, with most of the fastners appeared original. maybe a few members have noted this during there judging experence. thanks Ed

[Chuck S.]

Re: 72 headlamp shields screws

Another, question reguarding JM fastners correct or not, my 72 coupe has 6 black phosphate cross recessed round head phillips head screws without built in washers, as the JM says with capitive washers, I have looked at a few 72's and have been without the washers,

Has anyone noted that there may be a difference between the 70-72 cars? I know thats this is a small detail, but, Im in the process of correcting the last details on my car for spring top flite judging...

I haven't looked that close at this particular application on other cars, but for my late 70, those screws were black oxide cross recess pan head, sheet metal screws, #8 X 5/8" WITHOUT captive washers.

As I recall, those shields are attached to the support structure behind the grilles. In that case, I doubt the shields would have been removed for a repaint...the shields would have been masked in place along with the stucture, radiator, AC condenser etc. to save time and work. My opinion...trust the car and not the JM if you want authenticity; it may cost you judging points, but that could be said for many areas.

As for finish, my observations always call for black oxide finish when the fasteners retain a hard, relatively shiny dark finish after cleaning. If it were black phosphate, I would expect the cleaned finish to be dull, either from phosphate (gentle solvent cleaning) or from rusty steel (possibly after wire brushing). It is possible, in my opinion, that the specs for the screws could allow either finish, so my observation of finish is not necessarily correct for ALL headlight shield screws ever used 70-72. The provision of a captive washer for the same spec is a little less intuitive, but it may depend on screw head size/configuration and/or reasonable substitution during low availability.

I doubt either finish would see deducts in judging, nor will the washers, unless the judges are judging very closely and strictly by the manual. If a judge has never personally restored an original car of the year class, and/or observed and recorded the configuration of fasteners and other parts, they may be tempted to judge strictly by the manual ala recent report from the winter regional. JMHO

My philosophy on judging (strictly my opinion) is if the attribute is in compliance with judging experience, no deduct is taken in spite of the JM; but, if the owner has restored to the JM, however accurate it may be, then credit goes to the owner regardless of your experience, and the experience of other judges.

[Edward J.]

Re: 72 headlamp shields screws

Chuck, I think if you poled 20 different judges you may get 20 different answers, as I have been finding out. these cars were made with a number of different fastners and head markings and plating.

The judging manuel is a great soruce of information, but I think that if bolt or screw types are to explained in detail, that they should be as they are written for all of years involved sure as the 70-72 JM. I hope you see my point and others that may be involved in the next revision.

As spring rolls around I will be judged for my first time and like to follow the details of what the JM says, as I will be at a chapter meet, and I have done little judging myself and have OJ'd a few times.My first time was done with the JM going by each line item. Its was how I starting the learning Process.

[Chuck S.]

Re: 72 headlamp shields screws

Chuck, I think if you poled 20 different judges you may get 20 different answers, as I have been finding out. these cars were made with a number of different fastners and head markings and plating.

The judging manuel is a great soruce of information, but I think that if bolt or screw types are to explained in detail, that they should be as they are written for all of years involved sure as the 70-72 JM. I hope you see my point and others that may be involved in the next revision.

As spring rolls around I will be judged for my first time and like to follow the details of what the JM says, as I will be at a chapter meet, and I have done little judging myself and have OJ'd a few times.My first time was done with the JM going by each line item. Its was how I starting the learning Process.

I'm confused. If you're going to restore exactly by the JM, then why ask questions when there is deviation from what you see on the car?

I believe in keeping an open mind...I have seen too many instances where the originality of an attribute conflicting with the JM was beyond reproach. The JM didn't come down from Mount Sinai engraved on tablets of stone; it was written by individuals like you and me that have spent a lot of time looking at and restoring Corvettes. That doesn't mean that those individuals have seen all the configurations that existed 70-72, or even analyzed and tried to explain the differentials that surfaced.

I do not EVER expect all the possible variations of every attribute to be expressed in a TIM&JG manual. If we are to have a "reference manual" for restoration, and I heartily agree that is a good thing, we have to start somewhere. I reserve the right to disagree with those that write these documents when I see good reason, and to express my dissenting opinion when asked. If we assume that the JM is always right, as written, without discussion, better or more diverse observations will never see the light of day.

[Edward J.]

Re: 72 headlamp shields screws

Chuck, I don't think I want to change the screws as I believe to be original, I realize that the manuel is not to be used as a resto guide but has alot useful info to be used during the resto,and is explained in the front of JM manuel.

One of my points is that when they spell out something in the JM , shouldn't it be something thats expected since they rarely spell out fastners types and plating finishes. as a regular user on this TDB I am always looking for knowledge that will make me a better judge and I am someone that enjoys restoring these cars.

thanks for your responses, Ed

[Grant W.]

Re: 72 headlamp shields screws

HI Edward

Here is a couple of pics of what I think you are asking about "headlight shield screws" I have seen some late 70's having the71 to 73 screw.

Hope this helps.

Grant

[Bill L.]

Re: 72 headlamp shields screws

I have a late 70 and it had #8 screws with no washers either. If memory serves me the assembly manual calls out the screws without washers per the GM pn.

The screws in Grant's pics resemble the screws that hold the front grills to their brackets.


Bill

[Edward J.]

Re: 72 headlamp shields screws

Grant thanks for the pic.s, but, it would be nice to see maybe some other pic.s, my screw heads on my late 72 is round head phillips, I guessing #8, black oxide, no washers.

As I said in a prev. post, 20 different judges you would get 20 different answers. or maybe it should read 20 different cars and 20 different screws.

The screws that are for 71-73 do look like the grill screws ,All though they would make since for the sheilds.

I know as Terry M. said there are no virgin cars out there. I so beleive.

[Alan S.]

Re: 72 headlamp shields screws

Hi Edward,
Here are some pictures of the screws from the headlight shields from my 71, #6589. I'm quite sure they were on the car at delivery.
Regards,
Alan

[Bill L.]

Re: 72 headlamp shields screws

Alan,

That is what I believed to be correct based on what was on my Late 70.


Bill

[Warren F.]

Re: 72 headlamp shields screws

Those[Alan's] are also what are in my two '71's as well.

[Chuck S.]

Re: 72 headlamp shields screws

...That is what I believed to be correct based on what was on my Late 70...

The thumbnails certainly appear to fit my earlier description: "...for my late 70, those screws were black oxide cross recess pan head, sheet metal screws, #8 X 5/8" WITHOUT captive washers."

In my opinion, then, the TIM&JG claim of captive washers on headlight shield screws for late 70, early 71 cars appears to have been easily refuted with only three (now five) original cars. I rest my case.

If any specific description in the TIM&JG cannot be confirmed for the entire year class, the exact extent of the observation should be noted, or the specific text should be omitted from the TIM&JG.

Just in case anyone thinks the pictured screws have "round heads", they do not...those are pan heads. Well, they are what is sold in hardware stores as a "pan head"; it's actually a modified pan head. A true pan head as described by Machinery's Handbook has a constant thickness without the crown. A "round head" has a height close to fully half the head diameter, and the head diameter is smaller than that a similiar size pan head screw. Check out round head machine screws at Home Depot, and then compare them to the "pan head" screws beside them...the difference is easy to see.

[Edward J.]

Re: 72 headlamp shields screws

Alan, thats exactly whats on my 72 coupe, im amazed of the different screws that were installed on these cars. The one Grant posted are of what the Judging manuel explains for 68/70.

Grant, the post of Alans screw heads are what I have in mine.

[Chuck S.]

Re: 72 headlamp shields screws

...im amazed of the different screws that were installed on these cars. The one Grant posted are of what the Judging manuel explains for 68/70...

If true that the captive washers were on 68-early 70 (I have no opinion), then the fact that they were eliminated is not TOO amazing. Many of the planned changes in these cars over the years can be explained as evolutionary thinking to cut production costs. This mindset can aid the restorer in understanding what seem to be anomalies.

To begin with, the captive washer was probably used initially to provide a large area to distribute loads that would tear the screw heads through the shield, and insure that the screw head didn't torque the plastic when assembled.

But, like every manufacturer, GM was constantly looking to reduce the production cost. The captive washer screw is likely to have cost a miniscule amount more because more manufacturing processes and material was required. They likely figured out that a larger headed fastener, without the captive washer, could accomplish the required objectives at cheaper cost.

IF IT HAD GONE THE OTHER WAY, that is from "no washer" TO "captive washer", the likely scenario would have been that the shields were being torn off over too-small screw heads in the field, and the captive washer was the solution.

[Edward J.]

Re: 72 headlamp shields screws

Chuck, I think that the experienced judges will learn another fact on these screw heads used on the headlamp shields, not to say that may not be a known fact already, and for most these screws are of little meaning, but being someone that is trying to restore my 72 to what facts I have read in the JM ,I can say time will only tell with the next edition of the JM,

Chuck,grant,Alan, Thanks for you comments and pic's. Ive learned aliitle more to help me along the way with my quest. By the way Chuck I was incorrect with screw head description, pan head was correct.