Namerow

Thanks for the additional efforts. However, it's just hard for me to believe that the factory used a thinner sheet for floor pans than what they seem to have used for body panels like the rear quarters. At least, that's what your measurements are saying (i.e. 1.1mm for the rear quarter panel vs. 0.8mm for the floor pan). It's worth noting that the difference between 1.1mm and 0.8mm is just .012" (sorry for the switch from metric to inches, but most of us understand tolerances best when they're in thousandths of an inch rather than tenths or hundredths of a millimeter). How thick is the factory primer and paint? Or maybe that's an aftermarket paint job on your rear quarter? We're left two possibilities to ponder: 1. The factory floor pans really are made of thinner sheet than the factory body panels. or, 2. One (or maybe both) of your measurements (floor pan vs quarter panel) doesn't represent 'reality'. Maybe your quarter panel measurement was too high because the metal wasn't bare? Or maybe your floor pan measurement is too low because you accidentally abraded away some of the metal in the effort to get rid of the paint? Maybe both? In inches, you have the rear quarter panel and front fender measured at an average of 1.1mm, or 0.043". As I mentioned earlier in this thread, that would equate to a thinnish 18-gauge. Your new 0.8mm measurement for the floor pan works out to 0.031" which would suggest really thin 20-gauge is right in the middle of the spec range for 22-gauge.. FWIW, I continue to like 1.0mm (0.039") for the factory floors and body panels because: a) 0.8mm sounds too thin, and; b) 1.1mm seems like an illogical (off-spec) choice that would have struck the Nissan engineers as being not only more expensive to buy from the mill but also adding 10% more weight than 1.0mm and requiring higher stamping forces. That said, it's interesting to see ConverTT's report that the Klokkerholm rear quarter repair panels are made from 22 gauge! As always, comments welcomed

Table updated to show revised (refined) measurement for the lower front frame rail reinforcement piece... Panel Location Measured Thickness (t) Source Gauge (derived from ‘t’) Gauge (reported) Source Front Apron (engine compartment) 0.032” Jfa.series1 20 20 Grannyknot Tabco repair panels (all) 20 Manufacturer ConverTT Klokkerholm repair panels (rear quarter) 22 ConverTT Thick-gauge panels & pieces (which ones?) 18 2manyZs kmack Lower Front Frame Rail (OE) 0.050” Carl Beck 18 18 ConverTT Lower Front Frame Rail (ZeddFindings) 0.062” Namerow 16 Lower Front Frame Rail - Reinforcement plate (‘pocket’) at front crossmember mounting point 0.0787” (2.0mm) AZStory ~ 14 Upper Front Frame Rail (‘horn’) 0.054” Carl Beck ~ 16 Front Valence Panel 0.032” Namerow ~ 20 Front Crossmember 0.076” Namerow ~ 14 Door – outer skin 20 ConverTT Inner Rocker Panel 18 ConverTT Radiator Support 18 + 20 ConverTT Floor Pan (OE) 0.044” CanTechZ ~ 18 Floor Pan (ZCar Depot) 0.045” vendor ~ 18 Floor Pan Bottom Rail (ZCar Depot) 0.060” vendor 16

Point noted. However, 14-gauge sheet can be anywhere from 0.0697" to 0.0797" so your measuring gauge (sized at the median thickness of 0.0747") could register a 'no-go' even though the piece actually was made from "14-gauge" steel. More likely, however, is that this piece (like most of the other steel used in the S30) was made from sheet steel rolled to the metric standard by a Japanese steel mill. It seems very like that this doubler/reinforcement piece was stamped from 2.0mm stock (which nominally converts to 0.079" and would therefore likely register as 'too thick' for your measurement gauge's '14-gge/0.0747"' slot). Note also that 12-gauge is a big jump up in thickness from 14-gauge... 0.1046" vs. 0.0747", so an increase of 0.0299"... which is almost 1/32". From your picture, it doesn't look like your there's a mismatch of 0.03" between the S30 part and the 14-gge slot in your measurement gauge. It also looks like your 12-gauge slot would be way too big... All things considered, then, I like "14-gauge" for this part because it's very close* to what is most likely the real truth -- which I think is 2.0mm. (* 2.0mm/0.0787" vs. 14-gge/0.0747", so within 5% using the nominal design thicknesses). My purpose in starting this thread was to create a reference chart for selecting the right** sheet thickness to use for panel repairs. Since very few of us (in Canada and the US) have convenient access to metric-standard sheet steel, the best guidance for repair panel thickness comes in the form of 'gauge'. I suppose I could add a "mm" column, but that would confuse the heck out of everyone. (** Let me qualify my use of the word 'right' by adding that there's sometimes an incentive for using a thicker steel than the factory did. A good and common example is the bottom rail ('support') for the floor pans, where some owners choose to go with a thicker-than-factory steel and go full-length in an effort to better tie the front and rear sections of the 'chassis' rails together.)

Not that the metric system doesn't have its own moments. Consider the standard for determining the metre length unit. The basic unit of length in the metric system; it was originally planned so that the circumference of the Earth would be measured at about forty million meters. A meter is 39.37 inches. Today, the meter is defined to be the distance light travels in 1 / 299,792,458 seconds. Based in science? Yes. Intuitive? Not hardly. I like the definition of the kilogram better: The kilogram is almost exactly the mass of one litre of water. Consider, by contrast, the definition of the inch: The old English ynce was defined by King David I of Scotland about 1150 as the breadth of a man’s thumb at the base of the nail. To help maintain consistency of the unit, the measure was usually achieved by adding the thumb breadth of three men—one small, one medium, and one large—and then dividing the figure by three. During the reign of King Edward II, in the early 14th century, the inch was defined as “three grains of barley, dry and round, placed end to end lengthwise.” At various times the inch has also been defined as the combined lengths of 12 poppyseeds. Makes one pause when considering the implications of having a 427 cubic inch engine in your car.?

What was the rusted out mount shown in the #3 picture in your original post?

Every time I see how clean and open your workspace is, I want to cry. I have my garaged Z supported on wheel caddies (one caddy per corner, four caster wheels per caddy) and I have brace myself against a wall to generate enough force to make the car move. Looking on the brighter side, I'm thankful to have a paved floor, a roof over my head, decent lighting, and locking doors so that my tools won't vanish when I'm away from home. No social distancing issues either!

I read that coverage and I found it unconvincing. Conclusions being drawn far too early by media ("If it bleeds, it reads"). The Korean source cautioned that they weren't sure whether what they were seeing really was reinfection. And I'm certainly inclined to trust an official source from South Korea rather than one from, say, the Chinese government and media. As for the people who refuse to acknowledge the need for safe distancing, perhaps we should have them explain their 'Doesn't apply to me' attitude to an audience made up of doctors and nurses from their local hospital. Alternatively, offenders who contract the virus and require medical care should be instructed to join the special line at their hospital that serves members of the 'Doesn't apply to me' group. That would be the line that leads to a door opening out onto the back parking lot.

Maybe when June rolls around and your wife's honey-do list has finally been cleared and we're still locked down, you could spend some quality time inventorying your unwanted parts and putting them up for sale here on the CZCC virtual 'yard'. Might raise enough cash to pay for that that epoxy floor coating you've been promising yourself for the garage. Or maybe some of that cool, rich-guy modular flooring laid down in a chequered flag pattern? Or a giant 'Z'.

Did the aluminum spider fracture from vibration or was there actually corrosion going on? Reason I ask is that picture #3 appears to show another part of the drum drivetrain and there doesn't seem to be much doubt that that mount has failed because of corrosion. Did its failure then lead to stress fracturing of the spider?

Love your 'stamping press' setup!

New of my chart, updated with most recent contributions... Panel Location Measured Thickness (t) Source Gauge (derived from ‘t’) Gauge (reported) Source Front Apron (engine compartment) 0.032” Jfa.series1 20 20 Grannyknot Tabco repair panels (all) 20 Manufacturer ConverTT Klokkerholm repair panels (rear quarter) 22 ConverTT Thick-gauge panels & pieces (which ones?) 18 2manyZs kmack Lower Front Frame Rail (OE) 0.050” Carl Beck 18 18 ConverTT Lower Front Frame Rail (ZeddFindings) 0.062” Namerow 16 Lower Front Frame Rail - Reinforcement plate (‘pocket’) at front crossmember mounting point 0.0747 AZStory 14 Upper Front Frame Rail (‘horn’) 0.054” Carl Beck ~ 16 Front Valence Panel 0.032” Namerow ~ 20 Front Crossmember 0.076” Namerow ~ 14 Door – outer skin 20 ConverTT Inner Rocker Panel 18 ConverTT Radiator Support 18 + 20 ConverTT Floor Pan (OE) 0.044” CanTechZ ~ 18 Floor Pan (ZCar Depot) 0.045” vendor ~ 18 Floor Pan Bottom Rail (ZCar Depot) 0.060” vendor 16

Sorry, I missed this earlier note from @grannyknot. Wish I could remember where I got my gauge chart from (it dates back several years). The discrepancy between GK's values and those from my chart are large, so I just went looking for another source and came up with this one from machinemfg.com (website for a machine manufacturer). I wouldn't call it a definitive source, but the values coincide with the chart that I posted... www.machinemfg.com/sheet-metal-gauge-sizes-chart-inch-mm/#Sheet_metal_GAUGE_thickness_chart So then I searched for a chart for the American Wire Gauge (AWG) and discovered that its values agree with GK's... www.powerstream.com/Wire_Size.htm None of my sources are definitive. If someone wants to post the tables from an accepted engineering reference like Shigley's, that would resolve the issue once and for all (I never could afford that book when I was in school and just used my employer's copy after I got out into the workforce). It appears, though, that we've tripped over yet another facet of wacky world of 'gauge' measurements -- that is, that gauges have different 'thickness' values, depending on whether you're looking a wire diameter vs. sheet thickness. Another vote in favor of metric.

Truly harrowing how such a thick piece of steel can be eaten through by rust. I suppose it has to do with its location (up front and down low) and the moisture-retaining space created in the gap between it and the inner fender apron. Maybe residual warmth from the engine after being parked helped out too. There must have been a lot of salt-belt Z's that were just one pothole-in-the-middle-a-hard-corner away from having the front crossmember part company with the frame rails. On a similar note, I remember back in the day hearing a story about a Z in Montreal that broke in half after a minor fender-bender ?

I went over to my local small supermarket (would that be a 'mini-market', or just a 'market'?) on Tuesday morning. Arrived at 8:00AM for the seniors' hours (yes, I qualify -- and by a large margin, unfortunately). The store management had decided that they could handle 30 people inside at a time without getting people too close to one another. At 8:00AM (store opening time), the first 30 customers had already been let inside and I ended up at the back of a 15-person queue lined up outside. The speed of the line was painfully slow. Or so it seemed anyway. It took well over 30 minutes before I got into the store, meaning that the line was advancing in increments of about 2 minutes. Next time, I'm going to arrive 15 minutes early so that I can be in the group of 30 who are allowed in en masse when the store opens at 8:00.

One of the build threads on this site provided a step-by-step fabrication procedure for this exact piece. Unfortunately, I don't remember which thread it was. Maybe someone else will. It basically made up the piece in the form of a set of flat panels. Only straight-line bends and cuts were used. He had to weld in filler pieces to create the floor and the front and rear vertical walls of the pocket. If you think of how you could create the piece using cardboard and tape, you'll get the idea. It's too bad that the answer to this kind of question has to rely on the memory of other readers and contributors. One of the weaknesses of sites like CZCC is that the search tool depends on the words that the tread's author uses to describe their work. For example, what would you call this particular piece? One person might call it a 'doubler'. Another might call it a 'reinforcement' or an 'insert'. There's also the distinct possibility that the author of the build thread that I'm thinking of may have described his procedure without ever giving the piece a name.

I like the second table, esp. the fact that the standard dates back to 1922 and therefore encompasses the period when the S30 was being built. It indicates that the 1.1mm thickness offered by contemporary supplier Parker Steel (see my earlier entry in this thread) is not really relevant to the sheet used for the S30 body panels. It looks, instead, like 1.2mm (0.0472") would be closer to the truth. The JFE brochure provides some interesting insights into the cross-section of sheet steels available to modern-day automotive/manufacturing engineers for body pressings. With techniques like hydroforming and materials like high-strength and ultra-high-strength now available, things are a lot different than they were back in 1969.

We'll probably never get a better measurement of the factory floor thickness than that. Closer to 1.1mm than to 1.2mm, so let's call it 1.1mm then. BTW, both 1.1mm and 1.2mm are, according to a modern supplier of rolled sheet steel (Parker Steel / MetricMetal.com), legitimate standard sheet thicknesses for bulk metric rolled sheet... Unfortunately, this is one of those cases where the measured thickness doesn't align very well with American gauge standards... 0.044" places the floor panel right at the lower (thinnest) boundary for 18-gauge. Conversely, the upper (thickest) boundary for 20-gauge is just 0.0389". So, we can consider the factory floor panels to be either thin-ish 18-gauge or way-out-of-spec 20-gauge. We can also say that the floor panels are the same thickness/gauge as the main outer body panels (which, interesting to note, are commonly considered to be "20-gauge" but are, per my notes above, closer to 18-gauge than they are to 20). In the end, 1.1mm is probably the correct representation. Comments welcomed.

A key panel not reported on yet is the floor pan. Anyone? Easy to measure by pulling one of the drain plugs, but requires a vernier set up like CanTechZ's in order to measure properly.

Although it's now 30 years old, 'Carroll Smith's Nuts, Bolts, Fasteners and Plumbing Handbook' provides some great insights into fastener technology. Smith was an important part of the Shelby American racing story and a respected member of the American pro racing fabricators' community for many years. He is best known for his 'Prepare to Win' and 'Tune to Win' books, which were racers' bibles in the 1980's.

Small-block Chevy? Or maybe it's electric. Front axle looks like at came off a mid-60's AA/Altered Fuel drag racer. Just the thing for you and your friends to arrive in at the local casino.

Updated chart... Panel Location Measured Thickness (t) Source Gauge (derived from ‘t’) Gauge (reported) Source Front Apron (engine compartment) 0.032” Jfa.series1 20 20 Grannyknot Tabco repair panels (all) 20 Manufacturer ConverTT Klokkerholm repair panels (rear quarter) 22 ConverTT Thick-gauge panels & pieces (which ones?) 18 2manyZs kmack Lower Front Frame Rail (OE) 0.050” Carl Beck 18 18 ConverTT Lower Front Frame Rail (ZeddFindings) 0.062” Namerow 16 Upper Front Frame Rail (‘horn’) 0.054” Carl Beck ~ 16 Front Valence Panel 0.032” Namerow ~ 20 Front Crossframe 0.076” Namerow ~ 14 Door – outer skin 20 ConverTT Inner Rocker Panel 18 ConverTT Radiator Support 18 + 20 ConverTT

Well, it could be a lot worse, you know. In England, they came up with something called the 'British Whitworth' system for fastener threads and that is a standard that defies comprehension (I can hear keyboards in Britain warming right now and I expect that we'll shortly be seeing explanations about why BW is actually the best system in the world ?). Here in Canada, our government decided way back in 1967 that metric was the way of the future and decreed that it would be the national standard from that point forward. Unfortunately, our neighbours to the south didn't completely agree (although large parts of the American industrial community did, including the auto manufacturers). Canadians of my generation (boomers) have adapted reasonably well to jumping back and forth between pounds and kilograms, and inches/feet vs. centimeters/meters. Depending on what you're shopping for, the preferred measurement could be metric or it could be fps (sometimes both!). Some of our food containers have truly unfortunate metric sizings (454ml, for example), because the container is actually sized in the old 'quart/ounce' system but labelled to adhere to the legal metric requirement. Speaking of quarts and ounces, did I mention that our 'Imperial' quarts and ounces are not the same as our American neighbours' quarts and ounces? I suspect that younger Canadians can only function in metric. All of these measurement standards have been made to work acceptably* when kept confined to their own geographic sectors. It's only when you start mixing them that things get difficult. (* Well, sort of acceptably. In engineering calculations, the fps system requires an unfortunate concoction called 'slugs' in order to make things work out.)

I've been reading another thread that focuses on the new floor and frame rail stampings being offered by a shop in Florida (name?). I noted that there seems to be uncertainty over the actual OE panel thicknesses used for the S30's panels and stampings. Given the shear number of experienced S30 restorationists who have been participating in the CZCC website over the years, I'm a little surprised that we don't already have an in-place consensus on the gauges of the factory floor and rail stampings (not to mention all of the rest of the S30 structural and body panels). One would have thought that this would have been discussed and agreed upon long ago? @Patcon @ConVerTT @grannyknot @240260280 And yet... I've never come across a posting that pulls all of this information together in one place. So... here's a table that shows information that I've either collected from others in old posts or measured by myself from pieces from my 1970 and 1972 Z's (and the replacement frame rail that I ordered from ZeddFindings) (worth noting that measured thicknesses don't always line up cleanly against American gauge specs. My guess is that its because the Nissan OE panels were created from metric-spec steel sheet sourced from Japanese steel mills.) If you have a panel thickness measurement that you'd like to offer for any of the S30's panels or major stampings, maybe you'd like to consider posting it here so that we can build up a more complete library. Or, if you already have your own table of panel thicknesses, why not post it here so that everybody else can benefit? Panel Location Measured Thickness Gauge (reported) Gauge (derived by Namerow) Measured (or reported) by Front Apron (under Battery Tray) 20 Grannyknot Tabco replacement panels 20 manufacturer Thicker-gauge panels & pieces (locations?) 18 2manyZs, kmack Lower Front Frame Rail 0.050” 18 Carl Beck Lower Front Frame Rail - Zeddfindings 0.062” 16 Namerow Upper Front Frame Rail (‘Horn’) 0.054” ~ 16 Carl Beck Front Valence Panel 0.032” ~ 20 Namerow Front Crossframe 0.076” ~ 14 Namerow

In all my years living in various parts of Canada, I don't think I've ever seen anything like that. Thanks for sharing. BTW, snow-packing in and around air inlets can be one of the most challenging aspects of vehicle design and development. It's really difficult to simulate properly in a test chamber and climatic wind tunnel and field testing can be a hit-and-miss affair.

Probably a lot stronger than most Z's are when they first go up on a rotisserie!