Factory prime/paint/undercoat process

[alphadog]

I have searched and can't seem to find any resources from 50 years ago to confirm my suspicions, so maybe someone here knows...

I have a 72 TR6 USA version - stripped and ready for paint. I stripped the shell and back of fenders with a heat gun as they had undercoating on them - underneath the undercoating was the red-oxide primer (e-coat) with no trace of body color (Sienna). So, yes no body color in the wheel arches on the outside, or on the backs of the fenders/wings.

I know the bodies were e-coated in a red oxide, and the assembled bodies were primed with a white/gray and rubbed down, then sprayed with paint while assembled. And body with fittings was dropped on the chassis, but I would love to see more details around paint and assembly.

So my questions

1. As there is no paint in the wheel wells under the black undercoating, were these cars undercoated at the factory? It seems odd to think a car would leave the factory with red wheel wells and regular body color - I can't believe the body color adhered only to the undercoat, and not the primer. 
2. The car is undercoated on the floor pans, so obviously after assembly - maybe it was done at arrival in the USA or at the dealer?
3. Looking at many cars that haven't been repainted (not 100% anyway), I find the paint coverage around the door jambs excellent - hard to believe they got all that paint up inside the hinge and front wing area with the fenders on - is it possible they shot any color before the doors were on? 

I have seen some other discussions on this, but most seem to be opinions or conflict with each other. 

Thanks!

[barkerwilliams]

About 17 minutes 

 

 

 

[alphadog]

Thanks, I have seen this video and others - I see the guys spraying paint facing each other on the assembly line (no masks in some cases!) but it still doesn't answer my questions. 

Hoping to find someone who knows while the few that made the cars are still around. 

[astontr6]

On 9/8/2022 at 6:02 PM, alphadog said:

Thanks, I have seen this video and others - I see the guys spraying paint facing each other on the assembly line (no masks in some cases!) but it still doesn't answer my questions. 

Hoping to find someone who knows while the few that made the cars are still around. 

BL were not known for doing a good paint job? I have had my car from new and the top- coat started to fall off within 6 months in some areas. There was no undercoat as such only red oxide.

Bruce

[alphadog]

@astontr6

Thanks for the reply (sorry for my delay) - so your wheel wells were just red oxide? or they were body color and that flaked off? Curious what colour was your TR6 and if only red oxide in the wheel wells when new, did it look odd or not noticeable?

[astontr6]

20 hours ago, alphadog said:

@astontr6

Thanks for the reply (sorry for my delay) - so your wheel wells were just red oxide? or they were body color and that flaked off? Curious what colour was your TR6 and if only red oxide in the wheel wells when new, did it look odd or not noticeable?

 

Hi Alphadog!

The whole of the body was red Oxide then sprayed in the Topcoat of yellow. It did not adhere to the Red Oxide in places and started to flake off in places after a few months and was redone under warranty. The repainted areas have not given me any trouble again. But I don't know if another type of under coat was used on the bad patches. My car has never had a full respray and has all original panels but it was Ziebarted from new. I have had the odd rust scab appear, but these had been professionally repaired. I have just had it re-rust proofed with a similar product which is used in the North Sea oil industry.

Bruce.

[alphadog]

On 10/6/2022 at 5:21 AM, astontr6 said:

 

Hi Alphadog!

The whole of the body was red Oxide then sprayed in the Topcoat of yellow. It did not adhere to the Red Oxide in places and started to flake off in places after a few months and was redone under warranty. The repainted areas have not given me any trouble again. But I don't know if another type of under coat was used on the bad patches. My car has never had a full respray and has all original panels but it was Ziebarted from new. I have had the odd rust scab appear, but these had been professionally repaired. I have just had it re-rust proofed with a similar product which is used in the North Sea oil industry.

Bruce.

Thanks again for the reply. Every usa car I have seen has the rubberized undercoating in wheel wells and sprayed under on the tub. None on the frame has any under coating on these cars, and when the tub is pulled off the frame the red oxide is visible where it sat on the frame - so it is obvious that the under coating happened after assembly.  
 

Maybe ziebart was the standard here as well - it was certainly popular then. And the ziebart just pulled the color coat off when it was removed.

[astontr6]

9 hours ago, alphadog said:

Thanks again for the reply. Every Usa car I have seen has the rubberized undercoating in wheel wells and sprayed under on the tub. None on the frame has any under coating on these cars, and when the tub is pulled off the frame the red oxide is visible where it sat on the frame - so it is obvious that the under coating happened after assembly.  
 

Maybe ziebart was the standard here as well - it was certainly popular then. And the ziebart just pulled the color coat off when it was removed.

I paid extra for the Ziebart rust proofing, I believe that it was a Swedish Product used there because of their harsh salted roads in Winter and it came with a 10-year warranty.

Bruce.

[TRTOM2498PI]

3 hours ago, astontr6 said:

I paid extra for the Ziebart rust proofing, I believe that it was a Swedish Product used there because of their harsh salted roads in Winter and it came with a 10-year warranty.

Bruce.

What a fantastic product Ziebart is, too. I have seldom seen a rusty car, when a car has been Ziebarted from new.  The only time I have seen the odd rusty one, is a potential poor accident repair, where whoever had repaired the car, had not re-applied it, or not done it thoroughly.

[stuart]

2 hours ago, TRTOM2498PI said:

What a fantastic product Ziebart is, too. I have seldom seen a rusty car, when a car has been Ziebarted from new.  The only time I have seen the odd rusty one, is a potential poor accident repair, where whoever had repaired the car, had not re-applied it, or not done it thoroughly.

Not always so, Ive seen some where obviously the original application wasnt 100% correctly applied and water had got behind eventually in some critical places.

Stuart.

[PodOne]

Best rust proofed car I’ve ever seen was a Austin 1750 Maxi which had a yearly spray of old oil and diesel mix. Stunk a bit while it burnt off the exhaust but no rot and like new underneath. Can’t say it would be the first choice of the concourse boys!

Andy

[stuart]

16 hours ago, PodOne said:

Best rust proofed car I’ve ever seen was a Austin 1750 Maxi which had a yearly spray of old oil and diesel mix. Stunk a bit while it burnt off the exhaust but no rot and like new underneath. Can’t say it would be the first choice of the concourse boys!

Andy

Several of the "Old School" type garages down here used to have an outside ramp specifically for oil spraying of the undersides of customers cars every winter, good way of getting rid of the old oil from servicing! Really helped in the old days when there was no real thought of rust proofing cars from the factory.

Stuart.