Topic: C-4 Markings/Daubs

[bryancobb]

Thanks Tim,

Charles showes the 65 where the "OK" is reverse lettering in a black rectangle.
I guess in 68, the reverse was changed to a POSITIVE.

[TLea]

Thanks Tim,

Charles showes the 65 where the "OK" is reverse lettering in a black rectangle.
I guess in 68, the reverse was changed to a POSITIVE.

Way before that. If you look at Dave's 66 picture the OK is same and same location. Mine also had the dark red 4 digit # on the other side top

[Skyway65]

Anybody have a theory as to what all the orange paint was for?  It seems to be equally spread over both the V8 and 6 cyl versions with little regard to any real meaning.  Orange all over the tailshaft and bellhousing...hmmmm...

[bryancobb]

I'll bet Charles' C-4 Transmission Plant Employee Friend could shed some light on this subject, as well as the 4 digit red machinists' marking dye number.

[J_Speegle]

Anybody have a theory as to what all the orange paint was for?  It seems to be equally spread over both the V8 and 6 cyl versions with little regard to any real meaning.  Orange all over the tailshaft and bellhousing...hmmmm...

Likely IMHO some form or quick identification method.

[68 S Code]

The OK may not be reversed just upside down?

[Skyway65]

Likely IMHO some form or quick identification method.

Perhaps Jeff, but those orange paint marks seem pretty broad, messy and random; unlike the paint daubs and other color codes that we see.

[68 S Code]

Don't want to highjack the thread but any pics of a 68 C-6, Dearborn late spring early summer.

[Bill Cabaniss]

 I can shed some light on some of the markings. I worked at the FORD SheffielD aluminum casting plant in the mid 70's. The process we used had not changed from the 60's. The aluminum was poured into the case molds at 1140 degrees f. When I removed the part 90 to 120 seconds later it was still several hundred degrees hot. Before I could drop the part into a basket I had to write the shift # that i was working onto the part with a grease pencil so the part could be tracked down if there was a quality control problem. The part was hot enough to melt the grease pencil. That is why some numbers are wide and smeared looking. At the sheffield plant ,1 was midnight to 8 am. 2 was 8am to 4 pm. 3 was 4pm to midnight.  The center cases were also steel shot blasted with small steel shot in a blast machine the size if a small house. This process removed any excess flash that might be left from the casting process. I also remember at times engineers would take parts at random to the engineers office to perform critical q.c. tests. These parts would have substantial markings from engineering tests that had been performed on that particular part. This could explain why a few people have some unusual markings that others don't. Bill.

[bryancobb]

Hi Bill,

Thanks for your info.  It's interesting to get puzzle pieces from the ones who cut the puzzles.

Do you have any ideas about the orange spray paint on the tail cases and the center cases?

I also wonder about the 1140 degree temp you remember.  Doesn't aluminum melt around 1400?

Another question.  Did the tail cases not get shot blasted too?  The ones I have seen were very slick compared to center cases.
The blasted parts actually LOOK a little different color, because of the way they reflect the light.

[Bill Cabaniss]

Bryan, Let me clarify the temp. The 1140 degrees was the temp. of the molten aluminum as it was poured into the molds to form the parts. I only mentioned that part of the process to explain why the the part was still hot enough to melt the grease pencil markings. The orange spray paint could not have happened at the casting plant. It would have probably been shot blasted off in the blast machine anyway. I know you are wondering why the grease pencil marks survived the blaster. My best guess is the marking/melting process left the number very thick and  thus helped it survive the harsh environment of the blast room. One end of the blast area was called the big blast. In this area we blasted the c6 and later a.o.d. cases. On the back side was the blue goose area where we trimmed the c4/c5 center cases of excess flash and then blasted them . I worked in this area for about 1.5 years and do not recall blasting tail housings or bell housings. That could be the color difference you are referring to. After blasting, these parts were stacked into large metal baskets and loaded onto a train and shipped to the trans. assy. plants. Bryan, hope this helps, Bill.

[bryancobb]

Some pictures have been posted that show what appears to be a number (4-digit ) in a Souvenir Font, stamped with red, machinists' marking dye.  Does anyone have a clue or guess what the digits may be for my transmission in my Mar 66 car.

[bryancobb]

I have been getting info that says the transmission pan was painted black outside, Is that what you guys have seen?

[CharlesTurner]

I have been getting info that says the transmission pan was painted black outside, Is that what you guys have seen?

Haven't seen an original painted black, only seen natural.

[J_Speegle]

Haven't seen an original painted black, only seen natural.

+1 for any of the classic Mustangs