S30 Construction Theories

[26th-Z]

Ron,

It doesn't appear as though the space OR alignment is uniform. The number isn't level either. It makes me wonder how the machine that made the numbers is used and set up. More so because of the theory that it was ground in place rather than before assembly of the fire wall which does not have much working space. Are you talking about the 'carat' (^) between the 3 and 0? That looks to me like the head of the rotary tool was dragged a bit between the two numbers. I wonder if the "serial number grinder" resembles some sort of Leroy device. That process involves a lot of hand and sight alignment between various characters.

[HS30-H]

Great thread topic, Ron.

It occurs to me that so many questions could be answered by the staff of Nissan Shatai's ( now closed.... ) Hiratsuka plant. Kats has made good contact with some of them, and there's a whole world of questions that we could ask them. Worth investigating for the future.

As for chassis numbers, I shall have to make a mental note to refer to 'engravings' rather than 'stampings' in future. I'd certainly like to see one of the portable engraving / pantograph machines that they must have used.

As reference, here are close-ups of chassis numbers on a couple of other models from a similar time frame to 'our' cars - a PGC10 Skyline GT-R and a B210 Sunny Coupe. Note that these cars were not made in the same factory as our Zs, so the same type of machine must have been used by other Nissan manufacturing plants too. Subtle differences in font, as well as noticeable similarities?

[RIP260Z]

The chassis numbers are engraved for the 240z's as shown here, but what about the later models of S30/S31? Even though mine can't really be made out now, before it was painted, the chassis numbers looked distinctly "stamped". The "font" is all uniform, with the likes of the zeros being just like the zeros typed here, rather than the "egg shaped" ones in the pictures above. The "font" looks very much like the stamping on the chassis plate. Someone got a picture of a much later S30 of the chassis number?

Surely somewhere down the line, stamping would have been quicker on the production line?

Just adding to the mix,

Regards

Ian

[26th-Z]

The B210 photo is very interesting, Alan. It appears level and uniform in contrast to the other photos in this thread. One thing shouts out to me. Is the B210 engraving after the body paint? Notice what appears to be remnants of a tape just below the serial number? I am reminded of the S30-00002 thread with a similar "something" around the serial number.

[HS30-H]

Is the B210 engraving after the body paint? Notice what appears to be remnants of a tape just below the serial number? I am reminded of the S30-00002 thread with a similar "something" around the serial number.

Don't get foxed by the remnants of yellow paint around the 'Shatai Bango' on the B210, Chris. That's just left over from the Japanese 'Shakken' tests, where the engraved number is sometimes highlighted to make it more legible and show that it has been checked. All of that is a continuing and regular thing through the car's life in Japan.

I agree that the B210 engraving is very neat and regular, whereas S30-series Z engravings can sometimes be very haphazard. They can look a little wobbly on C10 Skylines too. I wonder if it's something to do with the awkward location of the engraving on the Z in comparison to the B210? There's plenty of space around the B210 engraving. I wonder if the machine was fairly unwieldy?

[mgood]

Here is my serial number for a 11/76 - 280Z. The number does not look stamped or engraved on, it look like it was cast in place.

[geezer]

It appears that either the equipment improved or the operators became more skilled by the time Michael's 11/75 build '76 280Z was produced. It is very well layed out, but my opinion is, if the paint was removed it would become obvious that it also was engraved. Also the B210 has a well refined appearance that seems to take human inconsistancies out of the equation. The PGC10 Skyline GT-R example is nicely done and perhaps more of a concious effort was put into its execution? Bonzi has a good understanding of the 60's technology that would have been used to engrave these numbers and can probably come up with a better explanation than me. I find myself comparing it to the operating principal of an old Wrico lettering set that I still have. I'm visualizing a small rotary cutter in place of the lead/ink stanchion, built into a compact, portable unit that is easily dialed in to the letters/numbers needed. There are several holes drilled into the firewall in this area that could have served as locating points for a small handheld unit. Is this along the lines of a "Leroy" device? Guess I should look that up.

PS - Ian, I know that what is quicker or more convenient does not always factor into how this would be done. In our North American plants we were directed by the Federal government to use special "rosette" rivets to fasten the VIN plates to the instrument panels. They were stainless steel and a real pain to drill out if nessesary to change a plate (which happened occasionally). The placement of the VIN plates were also not in an easily accessible location after the windshield was installed either. All meant to thwart the activities of the less scrupulous.

Edited September 16, 2009 by geezer

[EScanlon]

...From the backside you cannot see any evidence of the number being stamped. Looking at the numbers under the magnifying glass its easy to see the metal was carved out and not stamped. I would have loved to see this when it was done. I'm left wondering what the equipment used looked like...

Emphasis mine.

..., I think it is safe to say they were engraved. I agree on the specialized font that was used. It is unique and not easily reproduced. I did notice though, on my car the numbers are not spaced perfectly and are not positioned evenly horizontally either. ...

I agree that all this points to the numbers being engraved, but I would like to point out a couple of little points that beget questions as to whether the WHOLE number was engraved, or if part of it was stamped. And whether it was done in a single pass or multiples. I have questions as to what type of engraving bit would permit some of the edges left.

Look at the DASH on (presumed HLS30) "DASH" 11730 pictured above. The left most portion of it shows a FLAT triangular wedge, while the right edge shows a ROUND edge. I can understand a round beginning point and end to the engraving process (high speed circular bit), but could anyone explain how you get a flat WITH distinct angles?

That little bit of beginning also appears on the vertical bar for the number seven as well as it's "foot" or base. The base of the seven could have been done with multiple passes of the same rotary bit since the corners of the foot are rounded just like the beginning and end of the two "ones".

Yet, if you look at the last two digits, 3 and 0 both have very distinct angles. The 3 at the top end and the center, and the 0 a the top.

Thoughts?

E

Edited September 15, 2009 by EScanlon

[geezer]

Emphasis mine.

I agree that all this points to the numbers being engraved, but I would like to point out a couple of little points that beget questions as to whether the WHOLE number was engraved, or if part of it was stamped. And whether it was done in a single pass or multiples. I have questions as to what type of engraving bit would permit some of the edges left.

Look at the DASH on (presumed HLS30) "DASH" 11730

Some of the very questions I had, but have since ruled out stamping. Yes HLS30-11730. I wish I could have gotten better pictures. I'm in the running for worst photographer of the year. Everytime I tried getting a closeup the pics became blurry. This is where my old film camera with the macro lens would have been much more effective. Looking at it with a magnifying glass the milling marks were still visible in a few areas. I gave some thought to it being carved out with a larger bit and possibly chased with a much smaller one to further define the font or visa versa. What I thought was a symbol of some kind and Chris said, "looks to me like the head of the rotary tool was dragged a bit between the two numbers", could be the smaller bit? Regardless of the cutters used, there still is no evidence of being stamped from the backside. It will take someone with better eyes and equipment than me to solve this mystery. I would not underestimate Nissan, who could have used a complex or multi step process to create this distinctively unique font.

Edited September 16, 2009 by geezer

[kats]

Hi,

I found this You Tube, this is not a S30 but 180SX(240SX for export model).

This will make you imagine how the body serial numbers were stamped/engraved for S30. http://www.youtube.com/watch?v=Po4i0HHrAWA&feature=related

This Nissan Shatai HIRATSUKA factory made S30.I have been there 5 years ago as a factory tour.

From 1:18" to 1:30" , you can see how they are doing about body serial number,

"Shatai Bango Dakoku Basho" I can see they are listing names of operators with their assignment on the plaque,

From right to left,

"Dakoku Sagyou Sekinin Sya" ,an In charge of Stamping/Engraving,

"Dakoku Sagyou Sya" ,worker of Stamping/Engraving,

"A Sei " , Regular worker of Groupe A

"(A) Fuku" ,Vice(assistant) worker of Groupe A

"B Sei " same as A

"( Fuku " same as A

But it is hard to see their names.

kats

[geezer]

Thanks for the link Kats. I think it is incredible that you were able to find this! The engraving equipment shown is similar to what I would have expected to see. We cannot see the business end of the machine, but it is somewhat obvious how it works. What surprises me is, it appears that there are a series of levers for selecting the correct characters which require input from the operator/worker. I would have thought that a data link would be incorporated into this equipment, automatically selecting the characters as scheduled, during this time period. Or perhaps the machine is "online" with a broadcast system and the operator is doing something other than inputting the chassis number with the levers. Interesting.

[bpilati]

I am glad to see you bring this subject up again Ron. I am absolutely fascinated with the design and construction engineering of the S30. The sophistication of the chassis construction for the period is remarkable in my opinion. Now you bring to light the idea that the VIN was engraved in place - very interesting.

I think I have posted these pictures from the collection before, but these may help illustrate.

I first became interested when I picked up this photo of a complete floor from an eBay sale years ago. Then I started collecting pictures of the various metal stampings and repair parts from eBay ads. These, I assocated with the exploded diagrams and illustrations in the parts books to examine various assembly ideas. On a bare chassis like 26th was once, you can see the assembly welds contrasted with the fabrication spot welds. Then you and I got into that long e-mail discussion, Ron, and I collected some photos from Nissan corporate annual reports. This is a great subject!

So there's the guy that didn't spot weld my door right. :laugh: Wouldn't you just love to just pull one of those bodies right out of the photo? Where did you get the assembly line photos?

Edited October 19, 2010 by bpilati