'69 through '73 Steering Wheels - Wood, or Plastic?

[HS30-H]

I've been prompted to start a new thread on this subject after reading - for what seems like the thousandth time - somebody describing the OEM steering wheel on a late 1970 production HLS30UV as "Plastic". 

No. The OEM steering wheel on the '1969 through 1973 production S30-series Z was WOOD. Real wood.

They were manufactured for Nissan by specialist Izumi Motor Co. Ltd, based in Shinagawa, Tokyo. Izumi made a wide range of steering wheels for Nissan, as well as selling their own aftermarket 'sports' stering wheels with a cheeky 'Izumi' engraved script which aped Nardi, one of their inspirations.

Izumi used a patented high-pressure heat moulding process. Real wood fibres, impregnated with resin, were laid - following the grain - in a heated mould around the steel hoop of the steering wheel. High pressure, combined with that heat, moulded the wood permanently around the hoop and cured the resin. The result was a wood steering wheel, complete with finger grips on the rear, with no joints or seams. No splinters.

My theory is that people found them a little 'plasticky' or just couldn't believe they were real wood, and it stuck. After 50+ years it is hard to shake this off, hence me reading a comment on yet another Bring-a-Trailer auction from somebody who is convinced they are plastic.

Evidence: I've cut one up. I'm making a 'special' wheel using this 1970 production Izumi as a base (it was already damaged, so don't weep...) and can therefore show what's under the surface. I'll let the photos speak for themselves...

   

[SpeedRoo]

The wheels are actually a composite using wood fibers as the reinforcing element and the resin being the plastic. It is understandable some people refer to them as "plastic" rather than wood. Generally a "wood" steering wheel would be made up of shaped pieces of solid wood attached to a metal frame.

[HS30-H]

12 minutes ago, SpeedRoo said:

It is understandable some people refer to them as "plastic" rather than wood.

The people calling them "plastic" - I'd wager - haven't seen one taken apart as in the above photos. They call them plastic because everyone else does. As far as they are concerned, there is no wood in there at all. They are wrong.
 

15 minutes ago, SpeedRoo said:

Generally a "wood" steering wheel would be made up of shaped pieces of solid wood attached to a metal frame.

The only difference here is (your qualification of) "solid" wood. The Izumi wheel is wood attached to a metal frame. The part that people are calling 'plastic' is actually wood. Real, as in organic,wood. Look at the photos closely. That's not wood dust, wood pulp or wood shavings (as in MDF, for example), that is clearly grained wood. It splits with the grain. 

Split hairs too much here and you'll find somebody (maybe even me) telling you that your definition of "shaped pieces of solid wood" might also qualify as 'plastic' if they have been stained and lacquered...   

 

[26th-Z]

You are both correct but you are splitting hairs within an incomplete definition, IMO.  There are many ways to process wood, similar to our thoughts of processed cotton or wool.  In the manner of manufacturing a wood steering wheel, Izumi used a processing know in the industry as "oriented strand".  Oriented strand lumber products have been around since the 1940s.  Similar to high pressure lamination techniques, the oriented strand process allows tighter tolerances and strength to a reinforced product like the steering wheel.  And, the end product is seamless.  Great welding photos of the metal rim and spokes!

 

[SpeedRoo]

The steering wheels on my Aston Martins are wood rims, made from shaping a solid piece of wood. These are the traditional style of wood wheels built this way for a hundred years or more. When composites came along and combined resins/plastics with various reinforcing materials the rim was shaped in a mold using pressure and heat. Not many people consider these "wood" in the traditional sense. Hence, its understandable why some people call these plastic...and they are partially correct. I would not consider the wheels in my 240Zs as wood but as a molded composite. Trying to correct people and their use of various naming conventions becomes quite petty, we are all correct but in various different ways.

[HS30-H]

32 minutes ago, SpeedRoo said:

Trying to correct people and their use of various naming conventions becomes quite petty, we are all correct but in various different ways.

So when the guy on the latest Bring A Trailer 240Z auction refuted my explanation, then doubled down with "Steering wheels on Z's are plastic", you think it would be petty to correct him?

That's what I keep seeing. Almost every time these wheels are discussed you see someone - or more - calling them "plastic". It is clear that they think there is no real wood in there at all. Put a few facts in front of them - including the wood composite explanation - and they wriggle with "...yeah, but it's still got plastic in it" or similar.

I'm pushing back on that. 

1 hour ago, 26th-Z said:

You are both correct but you are splitting hairs within an incomplete definition, IMO.  There are many ways to process wood, similar to our thoughts of processed cotton or wool.  In the manner of manufacturing a wood steering wheel, Izumi used a processing know in the industry as "oriented strand".  Oriented strand lumber products have been around since the 1940s.  Similar to high pressure lamination techniques, the oriented strand process allows tighter tolerances and strength to a reinforced product like the steering wheel.  And, the end product is seamless.

Thanks. Next time somebody says "Steering wheels on Z's (sic) are plastic", you'll hopefully step up to the plate and introduce them to the pioneering 19th century WPC work of Michel Thonet, John Henry Belter and Isaac Cole as well as Mr Armin Elmendorf and his 1960s OSB patent.

Or you could just sit back and let me shout "they are WOOD!" at them...

[26th-Z]

Well, hold on there, Roo.  If they were made from one solid piece of wood, they would show end grain which they do not.  Further, the grain on the steering wheel does not run perpendicular to the circumference of the wheel, rather parallel to it.  Thus your Aston Martin wheel is made from a number of wood pieces, front and back, around the rim. 

[SpeedRoo]

@26th-Z a solid piece of wood rather than wood fibers or sawdust. As you say the wood is cut and shaped to fit around the wheel frame; it is not a molded composite of plastic and wood like the Datsun one.

[HS30-H]

3 hours ago, SpeedRoo said:

...it is not a molded composite of plastic and wood like the Datsun one.

Here's a question. Straight, no spin.

Just how much wood do you think is in the rims of these wheels? What percentage of wood, what percentage of "plastic"? What proportions.

Ballpark will do. You'll be guessing, of course. So ballpark is OK.

 

 

I'm looking at the pieces I've chipped off the wheel, and whatever "plastic" is mixed in there is pretty scarce. Most of it seems to be confined to the outer surfaces. I can sand through the shiny stuff and get to the underlying layers of (what I'm calling) wood fibre, and that wood fibre reacts differently than the shiny stuff does. It sands like wood. I splits like wood. It splinters like wood. To all intents and purposes it behaves like wood. 

The majority component of the wheel rim is wood. In composite form, yes. Of course. I've been pointing that out for years. But wood nonetheless.    

[kats]

Hi Alan, that is a great anatomy of our steering wheel. It is wood !Even it appears wood more than I  expected.

I remember when I asked if our steering wheel is wood , Mr.Matsuo said it is wood compressed with a very high power added some plastic (or a kind of material) . 
 

Alan , do you see “compressed “ phenomenon like Mr. Matsuo said ? I think Datsun 510 has a same steering wheel, I am curious about if there are any discussions about same thing among 510 owners ?

I want to ask it directly to an engineer of IZUMI but maybe impossible…

Kats

[Mike]

No matter what material, those photos could almost be turned into a piece of art!  Very well done!

Mike

[HS30-H]

8 hours ago, kats said:

Alan , do you see “compressed “ phenomenon like Mr. Matsuo said ? I think Datsun 510 has a same steering wheel, I am curious about if there are any discussions about same thing among 510 owners ?

I want to ask it directly to an engineer of IZUMI but maybe impossible…

Hi Kats. I remember having a similar conversation with Matsuo san, but I have also seen a period (early/mid-1970s?) Japanese magazine article which covered Izumi and their factory. Kind of a tie-up with their aftermarket wheel advertising. It would have been in Motor Fan, Motor, Driver or one of the similar Japanese monthlies and weeklies. I will see if I can find it again.

Yes, Izumi used similar techniques to make the 'wood' steering wheels of 510 Bluebirds, C10-series Skylines and several other models, as well as the vinyl/'leather' covered versions. Their simulated-leather moulded vinyl wheels - complete with faux hand stitching detail, as seen on the 'Datsun Compe' wheels - are also rather clever.

Izumi. An interesting company using technology to volume produce products that gave an Italianate 'hand made' feel. It makes me sad to see their fine work dismissed simply as 'plastic'.

[HS30-H]

My KPGC10 Skyline 2000 GT-R track car also wears an (aftermarket) period IZUMI steering wheel, similar to the Datsun Compe style vinyl with moulded stitching detail.

Note the 'Nardi' style 'Izumi' signature engraving on the RH spoke:

 

[HS30-H]

9 hours ago, kats said:

I want to ask it directly to an engineer of IZUMI but maybe impossible…

Sadly, but almost inevitably I think, Izumi was bought up and merged into the global giant Autoliv group some years ago. 

The old Izumi factory still continues in Atsugi, Kanagawa prefecture. It would be nice to imagine they had some sort of corporate archive.

 

[SteveJ]

To your point, @HS30-H, I asked my wife to do a light sanding and stain the steering wheel in my car. She used a regular wood stain and sealed it. The wheel took the stain great. I doubt "plastic" would have faired so well, and my wife, who has stained a lot of wood over the years, confirmed my doubts.

[SpeedRoo]

16 hours ago, HS30-H said:

Here's a question. Straight, no spin.

Just how much wood do you think is in the rims of these wheels? What percentage of wood, what percentage of "plastic"? What proportions.

Ballpark will do. You'll be guessing, of course. So ballpark is OK.

No need for guessing at all. Resin to reinforcement ratio would be 1 to 5% by mass depending on the manufacturing method, reinforcing material, its porosity and orientation. One of the reasons molded steering wheels were produced was to meet safety standards, traditional wood rim wheels could splinter in accidents and injure the driver.

[HS30-H]

2 hours ago, SpeedRoo said:

No need for guessing at all. Resin to reinforcement ratio would be 1 to 5% by mass depending on the manufacturing method, reinforcing material, its porosity and orientation. One of the reasons molded steering wheels were produced was to meet safety standards, traditional wood rim wheels could splinter in accidents and injure the driver.

So you're making my point for me. 

"1 to 5%" resin and 99 to 95% organic wood product, but you think I'm "nitpicking" when I call out somebody who says "they are plastic"?

 

Yes, obviously and famously, pearl-clutching safety standards saw their demise. '74 up they were no more. Hence the thread title.

[SpeedRoo]

Unfortunately you are always nitpicking and calling out anybody who doesn't agree with you. You always have blinkers on when it comes to Japanese cars for some reason. I wasn't making your point, just answering a simple question which you then had to spin after saying it was "Straight, no spin".

[HS30-H]

6 minutes ago, SpeedRoo said:

Unfortunately you are always nitpicking and calling out anybody who doesn't agree with you. You always have blinkers on when it comes to Japanese cars for some reason.

This whole forum is about "Japanese cars".

This thread focuses on a component which was made in Japan by a Japanese company using an innovative and (evidently) somewhat obscure process, and which is - clearly, repeatedly - misunderstood.

And blinkers? I suggest you might like to pay some critical attention to those who want to tell us that these are "American cars, Made In Japan"...

Rather than "calling out anybody who doesn't agree with..." me, I'm interested in getting to the truth. My eyes and ears are open to learning and every day is a school day. If robust, reasoned debate is a little too upsetting for you then by all means bow out.  

 

7 minutes ago, SpeedRoo said:

I wasn't making your point, just answering a simple question which you then had to spin after saying it was "Straight, no spin".

The whole point of this thread seems to have whistled over your head at around 1,500 feet. I started it in response to yet another "they are plastic" statement on Bring-a-Trailer.

You are guessing - as predicted - at the resin to wood content percentage, stating a generality as though it applies here. Of course, you're probably not far off, but - as I predicted - you are guessing just the same. I'm going on what I see in front of me. Feel free to chip (see what I did there?) the rim off one of these steering wheels and tell me what you see in front of you. No need to count the rings or get into dendrochronology though. Just a natural response to organic-derived matter will do.  

Yes, Straight, no spin. The rim is - I'll say it again - made from wood. Wood (hey, Cellulose!) plus a relatively minor content of resin of some sort (ironically, very likely to be cellulose-derived too) and not majority "plastic" in the sense implied by the people I'm kicking back against. You yourself are nit-picking by trying to refine this any further than that.

How about you stick up for Izumi some?

 

[RIP260Z]

Wood.

I suspect the plasticy "feel" is where vast majority of the resin ends up during the pressure and heat cycles, on the outer surface (and inner by the photos). I presume Izumi didn't then put a finish, say lacquer, on the steering wheels, and the end finish is the resin?

My CSP steering wheel looks very much like the early S30 one, and sands like wood, and for me that is a wooden one. I wonder if Izumi made them too....?

[HS30-H]

2 hours ago, RIP260Z said:

I suspect the plasticy "feel" is where vast majority of the resin ends up during the pressure and heat cycles, on the outer surface (and inner by the photos). I presume Izumi didn't then put a finish, say lacquer, on the steering wheels, and the end finish is the resin?

My *guess* - informed only by what I see - is that there must have been some sort of finishing performed on the outer surface with a coat of lacquer or varnish. When you sand them down you typically see an outer layer of clear, after which you get into the organic material. I can't imagine they would come out of the press tooling with a 'finished' rim. That would be too clever!

The other thing I note is that the steel part under the rim is bare metal, not painted. Therefore I think the spokes and centre were painted black after the rim was formed around the steel hoop part (high heat involved) and that may point to a certain amount of rim finishing being necessary too. 

2 hours ago, RIP260Z said:

My CSP steering wheel looks very much like the early S30 one, and sands like wood, and for me that is a wooden one. I wonder if Izumi made them too....?

Seems very likely, but I wonder if - given the CSP's 'premium' nature - Nissan upped the quality on it and specified a more hand-finished wheel for it? It certainly looks more 'Italianate' than the stock SP/SR wheels, and very Nardi-like. Is there a split line/joint in the CSP's rim?  

[HS30-H]

I think these 'collector's items' are worth saving for posterity:

I must say '71Zcollector' is my kind of guy. He knows plastic when he sees (and feels...) it and he's sticking to his guns. That's the spirit!

 

[kats]

Hi Alan, I saw the BAT comments. I am sure this thread will definitely clear the myth.  It’s a lot easier to clear than clearing Mr. Goertz myth .

 I did a bit search for IZUMI , I found this article , https://www.nttd-es.co.jp/magazine/backnumber/no9/no09-izumi.html

I think that was just a few years before being merged into Autoliv . This article is very interesting and proved their very high quality and skilled engineering. 

Also I found an interesting another blog , https://ameblo.jp/1119-4195/entry-12213393088.html

A gentleman talking about IZUMI steering wheel. His friend whose father was a president of IZUMI , 常泉彦三郎

Tsuneizumi Hikosaburo .What I am liking is he is talking about his friend was an engineer of Nissan , his friend was testing a radiator for Fairlady Z euro version (no mention of years ) , Nissan Germany claimed the car overheated, they said the car needs to be qualified continuous 230 km/h cruising . 
 

One day his friend visited his house in Frankfurt, took his 1975 Porche 911 2.7 for a round trip in Europe, his friend was so amazed by 911 . No overheating, fast and strong brake. 
 

Kats

[Zed Head]

I just skimmed over the thread.  But it seems likely that this would be a wood-fiber reinforced polymer composite, with the original bulk material in the form of what would be called "bulk-molding" compound.  A blend of wood fibers and reactive resin ( the precursor to a polymer) that would have the consistency of Play-doh.  In that era the typical resin might be a polyester, like they used for surfboards.  The mold might be pre-coated with a clear resin, similar to how hot tubs are made, maybe a polyurethane clear coat, for durability and weather resistance.  Then the molding compound and steel frame would be placed in to the mold on top of the previously sprayed coating and the mold halves pressed together to form the wheel, then the whole assembly placed in to an oven or autoclave for curing.  The end result is a wood-fiber reinforced polymer composite with a hard durable clear coating.  The coating is then polished to give the final surface.

So, definitely not just "plastic" unless you consider the wings of a stealth fighter to be plastic.  But, not really wood either.  A high-tech, for the time, product designed to look like wood but be better than wood.  Wood has problems.  Just one possibility.  You can't spend a lot of time arguing with people who rail against "plastic:".  The word is just too undefined, it doesn't really mean much.  Literally, it means "formable".

 

[HS30-H]

6 hours ago, kats said:

Hi Alan, I saw the BAT comments. I am sure this thread will definitely clear the myth.  It’s a lot easier to clear than clearing Mr. Goertz myth .

Ha ha! I'm always hopeful, but not so sure. I think we will see people talking about "plastic" steering wheels for many years yet. I still see Goertz getting credit for something he never touched (including the MF10 Toyota 2000GT).

6 hours ago, kats said:

I did a bit search for IZUMI , I found this article , https://www.nttd-es.co.jp/magazine/backnumber/no9/no09-izumi.html

I think that was just a few years before being merged into Autoliv . This article is very interesting and proved their very high quality and skilled engineering. 

Also I found an interesting another blog , https://ameblo.jp/1119-4195/entry-12213393088.html

A gentleman talking about IZUMI steering wheel. His friend whose father was a president of IZUMI , 常泉彦三郎

Excellent! And the president had such a great classical name too, almost like from a Taiga drama. So we can see where the 'Izumi' name came from. Thank you!

One of my key motivations with this thread is to somehow give due credit to Izumi for their fine work. And yes, I do think it is fine work. When I think about it, I don't know how they managed to make these steering wheels for Nissan at an acceptable cost. There's a lot of processing in there.  

Many of the parts suppliers for our cars were independent companies who specialised in their particular fields, often to an almost artisanal level. I have seen this many times in Japan. Such companies still exist, but their craftsmen have been retiring and/or dying out whilst bigger companies gobble them up. It would be sad to think that companies like Izumi came and went without people like us - who literally lay hands on their work when we interact with our cars - even knowing their name.