GM 9418970 Screw Assemblies; Non-Identical Twins

[Gary B.]

Gary

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[Michael G.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Gary,

GM plants had a significant amount of autonomy in how they built the car.

It was not that unusual for a GM plant's internal purchasing to order a "special" version of a standard fastener if, for instance, production found the captured washer on the print to interfere with something or not adequately cover a hole. Sometimes an engineering change eventually got issued, if they bothered to tell the responsible release engineer, sometimes not. It was also not unusual for plant engineers to authorize things like extra washers (to solve the second problem) without ever getting around to informing the release engineer. If they needed to do something like that to build cars, they did it, and got authorization later or not at all.

[Gary B.]

[Michael G.]

[Gary B.]

[Gary B.]

[Michael G.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

The other thing to take into account here is that St Louis was very large with several other high-volume vehicles built there. Its very possible that the screw with the different washer was used in high volume on one of those cars, so easily obtainable by the Corvette plant next door.

I’ll give you an example of how this happens. In 1997 my company introduced a new type of fastener I invented that can’t be cross-threaded. Initially, one six miilmeter screw was used in a Ford assembly plant, in one application. My company was contracted by Ford to make 5 million of them annually. They worked so well that word spread quickly up and down the assembly line and line operators would steal them from the job at the job station next to them, substituting them with no authorization in place of the specified part. Within a very brief period so much misuse was occurring that the plant was ordering 5 million per month, though we had no authorization to make more than 5 million annually. We made ‘em and Ford paid for ‘em. The plants do what they need to do.

[Michael G.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Just one more comment on part cost: When it comes to cost on such things the plant had its own budget. The Ford plant in the scenario I described was paying much more for the substituted part because it was initially priced at low volume and their extraordinary volume wasn’t taken into account. Nobody worried about the plant budget spent to fix problems, so it never came up. Of course these were the norms back then, I can’t speak for today…

[Mark F.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Hi Mike,

Just out of curiosity, did your new type of fastener have a Ford Material Specification covering the finish you were required to supply? If so, would they say that it had to meet an "XYZ" testing procedure (let's say for corrosion in this case) - BUT, they didn't care what color or coating material it was - as long as it passed the lab test associated with it?

In the late '70s when I was at Ford, I dealt with hundreds of different chemicals in their Plants - all of which were associated with an "M-Number" (probably morphed out of Mil-Specs). M-Specs said things conceptually like "...the product must remove all grease in one pass and leave no residue on the surface wiped..." The vendor was at liberty to use whatever mix of chemicals they wanted - as long as it met the spec and associated testing thereof.

Did that M-number concept also translate to physical parts, such as the one you invented?

Also, Multi-Spindle Screw Machines I observed in Detroit could crank out parts like that (maybe not yours, I don't know) at a rate of about 1 per second IIRC. That's 36,000 in one 10-hr shift. For volumes like you're talking about, I would imagine the screw machine shop making them for you were running multiple machines with the same setup...and maybe two shifts per day(?)...dunno

[Terry M.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Hi Mike,

Also, Multi-Spindle Screw Machines I observed in Detroit could crank out parts like that (maybe not yours, I don't know) at a rate of about 1 per second IIRC. That's 36,000 in one 10-hr shift. For volumes like you're talking about, I would imagine the screw machine shop making them for you were running multiple machines with the same setup...and maybe two shifts per day(?)...dunno

Mark & Mike & Gary
In the late '70s I had the opportunity to occasionally visit many manufacturing facilities in the western side of Chicago - as manufacturing was beginning to head overseas. One of those plants was Phoel Manufacturing -- ever see a head mark of a stylized P? This plant was two city blocks long (about 1200 feet or 366 meters). The lines of screw machines ran the length of the building. The noise was deafening and you couldn't see from one end of the building to the other due to the oil mist in the air. The machines popped out screws and bolts at alarming rates. The smaller screws were more than one a second. All the attendants did was keep the feed stock supplied and remove baskets of product; and clear jams. As we used to say in the military: "It was all a$$holes and elbows." Some of the product was cleaned in what would pass for industrial wash machines and barrel plated (https://www.youtube.com/watch?v=yiV6...el=AhrarAlam); while others were phosphated. The fumes from those operations cleared ones sinuses. Cheap labor wasn't the only reason many manufacturing plants left this country. I was glad to only have to be in there briefly and infrequently. Had I known then what I know now I probably could have picked up some of what you are looking for from the floor That was another fun thing about walking in there. Falling into one of those machines didn't seem like a good thing to do, but footing was treacherous due to product that missed the baskets or overflowed the basket.

[Joe L.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Mark & Mike & Gary
In the late '70s I had the opportunity to occasionally visit many manufacturing facilities in the western side of Chicago - as manufacturing was beginning to head overseas. One of those plants was Phoel Manufacturing -- ever see a head mark of a stylized P? This plant was two city blocks long (about 1200 feet or 366 meters). The lines of screw machines ran the length of the building. The noise was deafening and you couldn't see from one end of the building to the other due to the oil mist in the air. The machines popped out screws and bolts at alarming rates. The smaller screws were more than one a second. All the attendants did was keep the feed stock supplied and remove baskets of product; and clear jams. As we used to say in the military: "It was all a$$holes and elbows." Some of the product was cleaned in what would pass for industrial wash machines and barrel plated (https://www.youtube.com/watch?v=yiV6...el=AhrarAlam); while others were phosphated. The fumes from those operations cleared ones sinuses. Cheap labor wasn't the only reason many manufacturing plants left this country. I was glad to only have to be in there briefly and infrequently. Had I known then what I know now I probably could have picked up some of what you are looking for from the floor That was another fun thing about walking in there. Falling into one of those machines didn't seem like a good thing to do, but footing was treacherous due to product that missed the baskets or overflowed the basket.

Terry------

This reminds me of another story from WAY BACK in my working career: I was doing an industrial wastewater inspection at a company that manufactured transducer components. These components were very similar to printed circuit boards and used the same processes to manufacture. These involved the use of many toxic chemicals, acids, and chlorinated solvents. As the foreman was taking me through the facility I noted that the fumes in the place were almost unbearable. I also noticed that most of the people working there were, to say the least, very weird appearing. I commented to the foreman about the fumes and people, telling him that I guess those are about the only kind of people you could get to work in a place like this. His response was something I will never forget. He said "Joe, they weren't like this when they came to work here". Those were his EXACT words. I'll never forget it.

A few years later I had to shut this place down due to a MAJOR industrial waste discharge violation involving the intentional disposal of many 55 gallon drums of waste trichlorethylene to the sewer system. I still remember the name of the company and the name of the "corporate savior expert" brought in to try to save the company. But, I'll not mention either here. The company is long-since out-of-business and I'm sure the "expert" is long-since deceased.

[Terry M.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Terry------

This reminds me of another story from WAY BACK in my working career: I was doing an industrial wastewater inspection at a company that manufactured transducer components. These components were very similar to printed circuit boards and used the same processes to manufacture. These involved the use of many toxic chemicals, acids, and chlorinated solvents. As the foreman was taking me through the facility I noted that the fumes in the place were almost unbearable. I also noticed that most of the people working there were, to say the least, very weird appearing. I commented to the foreman about the fumes and people, telling him that I guess those are about the only kind of people you could get to work in a place like this. His response was something I will never forget. He said "Joe, they weren't like this when they came to work here". Those were his EXACT words. I'll never forget it.

A few years later I had to shut this place down due to a MAJOR industrial waste discharge violation involving the intentional disposal of many 55 gallon drums of waste trichlorethylene to the sewer system. I still remember the name of the company and the name of the "corporate savior expert" brought in to try to save the company. But, I'll not mention either here. The company is long-since out-of-business and I'm sure the "expert" is long-since deceased.

I would love to have one of those barrels of trichloroethane. In the electric utility industry we used to use great quantities of it. It is a great water displacer in addition to its grease cutting abilities. The fact that it will pull the grease out of your hands and any other body part it comes in contact with is only part of its' downfall, as you know. Some time when we are together I'll tell you about my experience with PCBs, but that is another story for another time. Another of the companies I got into was Victor Gasket in the days when asbestos was a prime gasket material. Again, another story for another time.

[Michael G.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Mark,

Sorry Mark, but I don’t know much about Ford’s material specs. GM is a different story though, I helped write many of their finish-related specs.

As for fastener manufacturing, though Pheol called on me when I was a Fastener Engineer at GM, I never visited their facility. I toured many such plants back then though, and in some, though not all, Terry’s description was pretty accurate. Today, in most fastener plants, though they certainly smell of hot oil, the vast majority of the oil vapor that Terry spoke of is now removed from the plant by giant ventilation systems.

I did serve as Director of Operations at a fastener manufacturer in the early 90’s. We made screws and bolts and most of our parts went to GM, Ford and Chrysler. Screw machines were rarely used to manufacture screws or bolts by then, the threads were no longer ‘cut’ into the surface of the part. The parts were made using today’s process, a combination of two machines, one a “header” that stamped the un-threaded bolt from a coil of steel and the “roller” a device that rolled the unthread “blank” between two dies and displaced the surface of the blank into groove in the dies, thus forming thread, similar to rolling a pencil between the palms of your hands. The parts we find on our Corvettes were almost exclusively made using the process I just described.

[Mark F.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

Hi Mike, Terry, and all...

Mike - Got it on the Ford thing…and very interesting on your bolt manufacturing comments. I have never personally seen a bolt made from a stamping and rolling process, but then again, the last screw machine shops I worked in were circa 1976.

Terry – you got it, man – the rod feed stock would rattle in the holders (like a gattling gun) and the noise was incredible! Oil mist ALL OVER EVERYTHING. Back then, I think almost all of those oils were mineral-based. Later on (early ‘80s) I think they were trying to move more toward water based lubricants (I recall seeing them in at least one engine plant – white in color). At least back then, one problem with the water-based lubricants was you had to add biocides to keep bugs from growing in the massive reservoirs (thousands of gallons) of stored lubricant waiting for reuse on all of these machining operations…they were nasty organometallic compounds IIRC - very irritating to eyes and respiratory system.

I took a walk down memory lane – and for those of you who may have never seen a screw machine in operation, here are several videos – most are multi-spindle (the stock rotates); the last one is a single spindle (stock indexes into the rotating cutter/shaper heads on the right):

https://www.youtube.com/watch?v=rOGdQgiBMS8 < gives you an idea of how loud these are

https://www.youtube.com/watch?v=szOzCd3U8dU < advert, but simple explanation of what they do

https://www.youtube.com/watch?v=__nuKHK2x3s < advert, but shows a range of products that can be made

https://www.youtube.com/watch?v=ga9T70S1XTg < single spindle

PS – from the web: “Despite what their name implies, screw machines produce more than just screws…screw machines produce a wide variety of parts and products. Examples include both standard and custom bio implants, fittings, miniature medical instruments, metal knobs, specialty fasteners, spindles, splines, keyways, threaded rods, tire gauges, and many other metal parts, machined to precise tolerances.”

[Timothy B.]

Re: GM 9418970 Screw Assemblies; Non-Identical Twins

It would be interesting to know something about the screw assembly used in the ‘63 model year for the door opening mechanism. That screw asm started out as GM 191985, then changed to GM 3845714 on March 26 of 1963. That 2nd screw changed to 9418970 on Feb 13 of 1964, which persisted at least thru 1967. My searches for the first two part numbers have come up empty.

Gary

Gary,

The 191985 (1963) door screw to the best of my knowledge is phillips pan head pan approx 1/2" long with a attached tooth washer. That screw was on lots of my inner door attachment parts, (regulator, door latch etc.) I can't say for certain but I believe that's 1963 the screw you refer too.