Broach Marks, stamp pad -- 12 years ago

[Wayne M.]

Then editor John Amgwert published the following photos (click on link below this pic for the VIN derivative stampng) on the front and back covers of the RESTORER. He took a poll, including a ballot in a subsequent Driveline issue. The results were that HALF believed that the stampings or pad finish were bogus.

He answered in a later isssue that this was removed from a wrecked '67 around 1970, "long before Corvette owners knew anything about restamping engines".

John's conclusion: the more we learn, the more we really don't know.

Plus ça change ....

[Wayne W.]

Re: Broach Marks, stamp pad -- 12 years ago

Looks good to me and shows typical broach marks.

[mike cobine]

Re: Broach Marks, stamp pad -- 12 years ago

I believe that issue had several pictures, and was posted as a survey. Or maybe this one is the results issue. Something like 50% guessed wrong on the whole survey.

Makes you wonder how many did or didn't receive their flight awards based on that accuracy of pad judging.

[Gary Schisler]

Re: Broach Marks, stamp pad -- 12 years ago

The same thing happened when Al Grenning did his discussion at the Pittsburgh Tri-State meeting a few months ago. He put up very high quality photos of pads with/without broach marks, hand stamped numerals/letters, bounces, etc. You name it, he had a photo of it. We did a raising of hands on each one for real versus forgery. I would say that better than 50% were wrong. The REALLY ugly stamp pads, the ones you would be embarrased to say were on your car, usually were the ones known to be authentic. Intersting.

It really said volumes, without saying a word, about this hobby and maybe the direction we are heading?
Gary

[Chuck S.]

Re: Broach Marks, stamp pad -- 12 years ago

It's an original pad.

John published my lengthy analysis without attribution, probably as an example of how extreme NCRS members can be in anal analyis...but I did get right answer.

The simplest logic as to why everyone should have known it was a real pad, besides the fact that it before huge profit potential for restampers, is the fact that HE is a base engine. If you're going to go to the time and trouble to restamp a pad, who would restamp a pad with a base engine suffix?...You might as well do one that will bring in the big bucks.

[Tom D.]

Re: Broach Marks, stamp pad -- 12 years ago

Partners:

Typically, what are the points lost if the judges agree that a pad does not appear original?

[Jack H.]

Re: Broach Marks, stamp pad -- 12 years ago

The Standard Deduction Table of the NCRS Judging Reference Manual answers this question:

(1) 25 points are awarded for a correct Flint/Tonawanda engine assy stamp.

(2) 25 points are awarded for a correct St. Louis VIN derivative stamp.

Note: point value increases to 50 points on the early Corvettes that weren't stamped with the car's VIN derivative.

(3) 38 points are awarded for proper 'typical factory production' stamp pad broach marks.

Most senior judges with experience in judging stamp pads understand there WAS a natural variance here due to tooling wear, specific composition of a given block's cast iron, and how hot/cold the block was from the casting process when it was broached. These judges ask themselves, "Could this pad, as I see it today, have left the factory like this?" instead of having a 'hard arse' attitude of demanding to see factory fresh broach marks indicative of the middle/end of the broach machine's wear cycle.

Unfortunately, there are some who take a harder view... But, that's why there's an appeal process in the Flight Judging proceedure. Owners have the right to politely challenge the judge's ruling to (1) the team leader, (2) the meet judging chairman, and (3) the national judging chairman (at Regional/National meets only).

In my experience, too few appeal and sit/stew over the results of honest mistakes in judgement calls regarding the stamp pad. Remember, our National Judging Chairman is a long time confidant of Al Grenning with YEARS of stamp pad judging experience....

[Harmon C.]

Re: Broach Marks, stamp pad -- 12 years ago

The pad in this picture clearly show broach marks. I am sure somewhere their is specifcations as to the finish. When I worked as inspector in an engine maching shop we used a profilometer as I recall,a long time ago, and their was a range for the head surface and smooth as a babys a-- was not in the range. I would say that all blocks left the factory and were delivered to the dealer with broach marks you could see. We judge as delivered so if they have worn off and are not their so what make the car good enough to take the hit and still Duntov.
A -130 Duntov is the same as a -10.

Lets try paint as our next topic!!!!!!!!!!

This one is dead

JMHO
Lyle

[Chuck S.]

Re: Broach Marks, stamp pad -- 12 years ago

Yes...Visible even in a photograph...an otherwise pristine pad, but not a good example of an original pad sans broach marks. You probably wouldn't have any need for high-powered optics, or even be a highly experienced pad judge, to know this pad surface was original...either that, or it would be one heck of a re-stampers Renoir.

Somehow, I can't see a Duntov award in my future. With each discussion like this one about the broach marks, I realize that I have seen "how the sausage is made", and that in the sausage-making process you can't always depend on getting sausage makers that know what the 'ell they're doing.

[Tracy C.]

Hey Chuck dude...

Your comment from this post sounds fun... "NCRS members can be in anal analyis"

Where do we sign up for this class? Do we hav'ta be in med school or is open to anyone on the membership roles?

tc

[Chuck S.]

Re: Hey Chuck dude...

You didn't take it yet??? I thought "Anal Analysis 101" was a prerequisite for membership. In fact, I thought some applicants got admitted directly to the graduate program...you already know what BS, MS, and PhD stands for right?