More Boring Numbers Info

[Michael H.]

Hate to beat this engine stamp pad numbers thing into the ground but I thought I'd post the results of a test that I just did. Most people probably didn't accept the 3/16" character size I suggested previously but the results of this latest test should say something.

I very lightly tapped the character slug into metal to measure the size. It measured exactly 3/16", just like it's supposed to.

I then moved to a new spot in the metal test strip and wacked the character about as hard as they were hit on the assy line.

Guess what??? The slightly deeper/longer/wider character is now just about exactly 1/4".

Could this be the reason many think these numbers were originally 1/4"? What does the JG have on this?

[nancy charles]

Re: More Boring Numbers Info

getting ready to do a restamp. what is the best weight hammer to do the job ?THANKS......

[Michael H.]

Stamp Character Close Up *NM*

[Michael H.]

Re: More Boring Numbers Info

Nancy,

Not 100% sure of the weight but if you send me your email address, I'll send you a pic of THE hammer in action at the plant.

[Michael H.]

Re: Stamp Character Close Up

Above scan is a close up of the actual steel type, or slug, that fits into the holder. The obvious angle on the sides of the character should help explain why the stamped character size/height on the engine ID pad increases as the depth in the block increases.

If this character sinks .020 or .030 deep into the cast iron ID pad, the height of a 3/16" character can easily increase to 1/4".

If the original tool used at St Flint/Tonawanda was 1/4", I wonder how much taller the characters in the pad could be. Anyone have any dimensions?

[Mike McKown]

I shouldn't be boring to the numbers people.

I think it sheds an intelligent insight into why the numbers appear different size than whatever is generally accepted. It also explains (could) why you have (individual) taller stamped characters in the series. Suppose your online stamps were worn quite a bit from use and let's say you knocked a chip out of one making it illegible. It then gets replaced by a new, slightly taller, unworn stamp wich will now take the initial force of the hammer. What size character will this now be in relation to the others?

[John H.]

Re: Stamp Character Close Up

Measured an "I" character on my original '67 Flint pad with dial calipers, and it's .206"; light-to-medium stamp depth.

[Mike McKown]

Re: Stamp Character Close Up

John:

Your car must have been built before lunch. What would it be after lunch? LOL.

[Michael H.]

Re: Stamp Character Close Up

I think we're on to something here John. Looks like you, Mike McKown and I are the only ones interested though. Still like to know what, if anything, the JG has on this. Hope judges aren't taking points off for block numbers that are shorter than their published specs.

[John H.]

Re: Stamp Character Close Up

Michael -

'67 JG sez engine plant stamp character height is 1/4" and VIN derivative stamp character height is 3/16"; don't have the other JG's, but that's probably common to all.

[mike cobine]

Re: Stamp Character Close Up

I think a lot of people are interested, but after years of "this is the way it goes on ..." that most just follow.

I have seen engines stamped that if you posted the picture here, 95% would say restamp, yet they were on engines that no one would bother to restamp and old enough that they had to be before restamping. 307 in El Camino 25 years ago, for example. A '69 327 out of an Impala, and so on. Numbers crooked, numbers obviously handstamped one at a time (irregular spacing and height alignment) and so on. Letters added to the suffix after and completely different font.

But we are told Corvettes are different.

So I think most are just watching and listening and seeing where this leads.

[Patrick H.]

Re: Stamp Character Close Up

Agreed.

Mike McK and John have "been there" and Mike Hansen visited a lot.

Now, ask a medical question and I'm all over it.
Or, ask a 70-72 question and watch me beat the pants off both of them.

This information adds to what is in my knowledge base, but as none of my cars are at my home for close examination and I don't have 30 years of experience, I look and listen.

Patrick

[Donald T.]

Re: Stamp Character Close Up

5th edition 65 JG has engine ID at 3/16" and VIN at 5/32. Odd that it is different from the 67 JG.

[Michael H.]

Re: Stamp Character Close Up

I agree Mike, most are just following. Very few ever take the time or have the correct information to make needed changes/corrections in the manuals and that's the whole problem. Once something is in print, it automatically becomes law for some reason, even if it is incorrect.

My point of all this is simply to protect original cars. If an all original car shows up at a meet and a slightly "over aggressive" judge rejects the characters on the pad because they're a "little too short", that original engine car is marked for life as a restamp. This happens all too often and just a slight correction in the 63-67 JG's can solve the problem but I doubt any of this will ever actually change anything. We tried this with the 63 hardtop and all the work wound up in the garbage can. I totally disagree with this line of thinking and as long as they allow me to continue ranting on this discussion board, I'll post my thoughts and information. I was involved with the study of block stamp pad characters before most of the rest of the Corvette world even knew they were of any importance so I feel I can add something valid and useful. I'm not trying to change the entire judging system but it seems like it. Small adjustments in the JG's should be normal and expected along the way because it's a "work in progress" and will continue to be that way forever. It's just irritating that the impression given by those in charge is just the opposite. Ask Duke if he was successful at making a small change in the 63-64 manual a few years ago. How about the wacky caliper casting numbers in the 66 JG. I wasn't able to convince anyone they were incorrect and even Joe Lucias postings were ignored and number info doesn't get much more accurate than from Joe. The list of errors is long and every day, someone gives up their correct original 66 calipers because the JG states a different number is correct.

I believe the majority of todays owners really don't care about what's actually correct on their cars but are only concerned with what the JG states is correct so they can get their top flight and go impress their neighbors. I suppose I'm part of an ever shrinking group of old geezers that still care enough to try and make things right but it's not working.

My original thoughts on the matter were to slightly adjust the manuals/JG's to include a wider range of dimensions for characters. If the small number group were to be changed to "from 5/32" to 3/16", and the large number group changed to "from 5/32" to 1/4", it would cover the entire range of possible sizes for the numbers found on genuine blocks. Not likely it will ever happen though but at least owners will have a little ammunition when they have their car judged if they copy and print out John Hinckleys post above. I would consider anything he posts as absolute, on the money.

By the way, any character OVER the max sizes I listed above is automatically suspect as far as I'm concerned but that's just my opinion and I'm kinda new at this.

[Mike McKown]

IF, somebody had access to Flint purchasing record

or had a contact in the company that sold the gang stamp holder, wouldn't you go a long way toward proving/disproving character size of the stamps? I'd just about bet that whatever they bought in 1960 was what they bought in 1970. Why change and obsolete all your punches? They certainly wouldn't have mixed them during the model year.

Now, just to give some of you a reality check: Occasionally, when the regular on line operator would take off a day, a utility man would show up on the job. His sugar level on that particular day could have been high or low. Depending on that level, he might just beat the hell out of the gang stamp or he might just "tap" it with the hammer. If the sugar was high, it was okay. Low, well, illegible stamps are not acceptable. So, a good ass eatin' was about all it took to get things back in bed. This is from a former General Supervisor over an engine dress line.

I say this only to support what Michael is saying about the aggresiveness of the stamping. It could vary from engine to engine, day to day, regular operator to absentee operator, plant to plant, etc.

If you have a light stamp and it is 3/16" and a hard stamp that is 1/4", that's very believable to me.

All we cared about was, "is it legible"?

Based on what Michael has illustrated, I hope nobody has suffered a point deduct for "tall" stamps".