1 hour ago, HS30-H said:

But we are only looking at the S30-series Z range here, so - as far as I am aware from looking at period documentation - no Cadmium was used when 'our' cars were made.

I was looking for a before and after within Nissan Motor company or the Japanese auto industry as a whole. If Nissan never used cadmium then it seems illogical that they would start in 1969. The S30 is just another car of course. The same fasteners were certainly used across the model range. If they used cadmium in 1965 on a different model, you'd expect them to keep using it on the S30 unless they had a reason to change. When was the shift?

And, on your final point there - still no evidence that supports your statement, besides a Nissan document that identifies an alternative plating material. If you had a document that showed cadmium from earlier years next to your document that shows zinc, that would have some weight. Evidence that Nissan removed the word cadmium from their documents would be telling.

So far, there have been many many words written on sparse evidence. 1970 was so long ago. All of that paper and ink. How did they get anything done?

On 8/20/2025 at 2:18 AM, Zed Head said:

I was looking for a before and after within Nissan Motor company or the Japanese auto industry as a whole. If Nissan never used cadmium then it seems illogical that they would start in 1969. The S30 is just another car of course. The same fasteners were certainly used across the model range. If they used cadmium in 1965 on a different model, you'd expect them to keep using it on the S30 unless they had a reason to change. When was the shift?

I have taken the time to research this on the Japanese side, trawling through numerous Japanese market factory parts manuals for Nissan models made during the 1960s and early 70s period. I found some pointers. Dates quoted are the dates for the publication of the parts manual concerned:

*Model 31 Nissan Cedric - 1963 - Both Zinc and Cadmium protective coatings applied to fasteners/components.
*Model 310 Nissan Cedric - 1964 - Both Zinc and Cadmium protective coatings applied.
*Model 410 Bluebird - 1964 - Both Zinc and Cadmium applied.

Then,
*B10 Sunny - 1966 - Zinc.
*510 Bluebird - 1967 - Zinc.
*T44 Nissan Miler (ex-Prince) - 1968 - Zinc.
*T65 Nissan Clipper (ex Prince) - 1968 - Zinc.
*Model 60 Nissan Patrol - 1968 - Zinc.
*521 Pickup - 1968 - Zinc.
*C30 Nissan Laurel - 1968 - Zinc.
*A30 Nissan Gloria (ex Prince) - 1968 - Zinc.
*SR311 Fairlady - 1968 - Zinc.
*130 Nissan Cedric - 1969 - Zinc.
*C10 Skyline - 1969 - Zinc.
*C20 Vanette - 1970 - Zinc.
*GC10 Skyline - 1971 - Zinc.
*A-321 Cabstar - 1971 - Zinc.

...so, judging from the above, it seems likely that Nissan's use of Cadmium for protective coatings was discontinued around 1965. I also searched factory parts manuals of Prince Motor Co products (Prince were forcibly merged with Nissan in 1966) but they carry no data on protective coatings for their parts.

On 8/20/2025 at 2:18 AM, Zed Head said:

And, on your final point there - still no evidence that supports your statement, besides a Nissan document that identifies an alternative plating material. If you had a document that showed cadmium from earlier years next to your document that shows zinc, that would have some weight. Evidence that Nissan removed the word cadmium from their documents would be telling.

Your move.

Good information. Thanks for the followup.

1 hour ago, HS30-H said:

On 8/19/2025 at 6:18 PM, Zed Head said:

And, on your final point there - still no evidence

There was none, now there is some. Well done.

On 8/19/2025 at 9:06 PM, Zed Head said:

Taking sides doesn't lead to learning. Independent thought does. HS30-H might be trying to influence 26th-Z, or just expressing surprise.

I wasn't taking sides on the cadmium versus zinc issue. I have no knowledge or expertise to bring to bear on that topic. 26th-Z said "but how does this all matter", which is what HS-30H was referring to with the Brute quote. I think one of the hallmarks of this group is believing that details matter. My comment was meant to commend that behaviour. And Zed, you're definitely one of the people who cares about detail in my view. I don't always enjoy the exchanges themselves, but I think we all benefit from the willingness to engage, and the level of knowledge that results. Sorry that I wasn't clear.

I was just preemptively trying to avoid a digression. It felt like we were making some progress in the discussion.

I'm still curious about the test results that Carl Beck got. Could a supplier have replated cadmium plated hardware? We now know what Nissan specified but is it possible that there is actually cadmium-containing hardware out there? Doesn't look like they said avoid cadmium, they just specified a different finish. I assume that Nissan outsourced that type of work, that they didn't have a plating operation of their own.

17 hours ago, davewormald said:

I wasn't taking sides on the cadmium versus zinc issue. I have no knowledge or expertise to bring to bear on that topic. 26th-Z said "but how does this all matter", which is what HS-30H was referring to with the Brute quote.

Thanks for noticing the Shakespeare quote and the intention. I think all this really does matter. It's not going to cure cancer or bring world peace, but it is one of the things we have traditionally done here on this forum and drilling down into the details like this helps us to understand the cars better.

17 hours ago, davewormald said:

I don't always enjoy the exchanges themselves, but I think we all benefit from the willingness to engage, and the level of knowledge that results.

Well said. Yes, sometimes the exchanges are less than pretty but that is the type of thing that happens when somebody pokes their head above the parapet and questions the status quo. I often remark that such exchanges may give off a fair amount of heat and noise, but also a little light.

15 hours ago, Zed Head said:

I'm still curious about the test results that Carl Beck got. Could a supplier have replated cadmium plated hardware? We now know what Nissan specified but is it possible that there is actually cadmium-containing hardware out there?

But - again I ask - what's the origin of the "It's Cad" narrative relating to the Z? Where is it actually written? I see no source except long-held belief which appears to be built on presumption.

15 hours ago, Zed Head said:

Doesn't look like they said avoid cadmium, they just specified a different finish.

Looks like the goalposts are being moved again.

15 hours ago, Zed Head said:

I assume that Nissan outsourced that type of work, that they didn't have a plating operation of their own.

The whole point of the N.E.S. Nissan Engineering Standard was to ensure that fasteners could be specified and supplied to a fixed - trusted and repeatable - system. I've already given an example - from a Z-specific factory parts list - of the way an NES part number suffix could denote a particular finish (Zinc electroplating in the example I gave) on a given class of fastener, and it applied over the whole range of Nissan products in the period we are talking about. Nissan would have been using tens of millions of such items in their manufacturing operations, so it was natural for them to have a system to support that and huge manufacturing facilities for pieces to that standard.

To imply that there was some sort of back door where Cadmium-plated parts slipped into the supply chain - and specifically on the S30-series Z car's production process - seems desperate to me.

And "outsourced"? You remind me of Carl Beck telling us that Nissan Shatai was nothing to do with Nissan and that Nissan had 'outsourced Z production to a different company'.
Such musings don't seem to take into account the complex interlinked structures of Japanese Keiretsu.

https://nissan-neji.com/

4 hours ago, HS30-H said:

But - again I ask - what's the origin of the "It's Cad" narrative relating to the Z? Where is it actually written? I see no source except long-held belief which appears to be built on presumption.

You wrote it yourself. Up above where you showed that cadmium was used through 1964. Cadmium was commonly used as a plating material in the automotive industry. It was so common that the shortened "cad" was used to describe plated parts.

The problem is that the transition away from cadmium has not been clearly communicated. And assumptions have been made, like the claim that cadmium was banned in Japan. No written documentation of that seems to exist, for the time frame of the transition. The transition away from cadmium seems to be more anticipatory, expecting future bans, or limiting future liability. It was a choice, and therefore there was no regulatory reason not to use it. Ran out of zinc-plated stock? Use the old cad stuff. It's legal. Write up a QA exception. (Manufacturing world realities).

The open question is about the parts that Carl Beck had tested at Honeywell. Did they come from a 240Z? Were they original to the 240Z? How did they get there? Possibilities have been proposed. Nobody has said that all 240Z's used cadmium-plated parts. Only that cadmium-plated parts were found on a 240Z. Not the same thing.

The cadmium question exits on other car forums. Just as entertaining. Lots of misinformation.

https://forums.pelicanparts.com/porsche-911-technical-forum/164007-metalurgists-educate-me-please.html

It seems to me a lot of weight is being put on what Carl Beck reported of what someone at a materials lab 35 years ago told him.

What if the guys in the materials lab were busy, stuck Carl's bolts in the drawer and fobbed him off when he came back?

Why would anyone believe such an anecdote in the face of a document from Nissan at the time saying what they used?

Just as OEMs today thoroughly check suppliers work against the spec, I'd be very surprised if Nissan in the 70s accepted cad plating when they'd specified zinc.

Edited 3 hours ago3 hr by jonbill

15 minutes ago, jonbill said:

Why would anyone believe

That's a philosophical question. No simple answer...

It wasn't just a materials lab. It was a very reputable high tech company that he worked for, that had its own internal materials lab. Very common for large research-based corporations. And, you can see that he's not claiming that all 240Z hardware was cadmium-plated. He's suggesting that some of it might be. He writes very clearly. I think that his words have been distorted a bit throughout the cadmium conversation, trying to make a gray situation black and white. Sometimes you just have to live with the uncertainty. And be careful, as Carl suggests, if you're not certain. There might be cadmium.

On 8/14/2025 at 3:19 PM, Carl Beck said:

About 35 years ago, I was in the process of restoring a 240Z, as well as parting out another for spares. I took an assorted group of 10 or 15 nuts, bolts, washers and couple small parts off the Z's to our Materials Lab. "Our" being Honeywell Space and Strategic Systems Lab. A Materials Lab with men and equipment that supported putting men on the moon and probes on other planets. 

I ask the guys to tell me what was used for plating and corrosion protection, as I intended to have them re-plated.

After testing them, they told me they were Cad. plated and given a yellow chromate conversion bath- and to be sure to wear a mask if I used a wire wheel ((bench grinder)  to clean them up. Cadmium is very toxic and you don't want to breath any in.

Given that the OEM fasteners on a now 50+ year old 240Z, treated with a little penetrating oil will break free and unscrew, without twisting off, is witness to me of Cadmiums use.  That doesn’t happen with zinc plated fasteners in automotive use. In addition to Cad. plating having three to four times the durability of Zinc, Cadmium offers increased lubricity, so threaded fasteners release and unscrew. 

If you are not absolutely certain - best advice is to treat them as having Cadmium Platting..and be careful how you handle and clean them up. 

Our History

Sounds like the argument for god. "Yes Darwin, Einstein et al, you may have shown how everything that is may have come from nothing, but you've not proved that Nissan didn't ship any cars with cad plate bolts in the 70s"