Paint thickness

[Bob G ✝︎]

Kopie:

I hit the wrong bottom and whoosh my post disappeared.

For what it's worth, the car I should have bought, but didn't because of replaced front fenders and rear quarter, as well as filler in all fenders on the bottom is now on Ebay.  Whoever bought it says it was originally a 4speed so maybe it got your 5speed! Thanks for all of the input!  I consider this a valuable source for advice and knowledge.

So here again is my question. I read your post on metering the fenders on a previous fender bender fix on a Pagodda SL. I am familiar  with this proceeder since I was in the automotive appearance field 38 year.  I own a Defasco electronic coating meter that will measure steel and aluminum coating.
since it it my conception that  most of the body work and metal finishing was done by hand when these cars were produced I suspect that higher the .005 mill which is your average coating thickness on today's vehicles might be much higher as to in the range of 00.7 mills.
Since I have no information to document the coating  thickness on an original unrestored paint job with original body panels . what  is your educated guess to proximate what the factory coating thickness was taking in consideration for  lead. primer filler and paint?

Best  Regards
Bob Geco

[hkollan]

Bob,

By using an electronic coating meter similar to yours, that also does Aluminum and steel, I've found that original paint has a thickness
of around 0,2mm. I measured  various Mercedes models from around 1970.W111s and W109s).
I didn't measure any areas where I suspect lead was used, so not sure how that would affect the meterings.
I would assume that original paint on a W113 to be about the same thickness.

Regards,

Hans

[Bob G ✝︎]

Hans

How are  you determining that mill thickness? Are you subtracking it from the primer and precoat from the factory ?

I am not quitesure if Mercedes-Benz up until the later years of 1970 used an acid dip primer tank to submerge chassis's and body before it got to the paint department. in it self you would have to logically add 1 to 2 mill before the paint was applied?

An intresting  question to fine in the Mercedes-Benz archives would be the painting process of  older classics like ours . I do not know if robotic  painting  was used back then . It be interesting to fine out  if these cars were spray painted by  the paint shop and how they were inspected and finished before delivery to the buyer or dealer.

my dads 1968 280SL when new  seemed to have a beautiful enamel paint job and if you looked closely you could see the famous orange peel effect of early enamel paint systems.

Bob Geco

[hkollan]

Bob,

I must have misunderstood your question. When referring to original paint thickness, I did not distinguish between the primer, base paint and the optional clear cote for metallic paints, when looking at the thickness. Not sure how you could do that except by mechanically removing a layer and measuring before and after. And then you need to find a pagoda owner willing to sacrifice his original paint for the process. :-)
So the approx number of 0.2mm is just what the instrument shows, from bare metal to the surface of the paint.
 
I could make a qualified guess however, since a 1970 300 SEL 6.3 I own with most of the car with original paint in tobacco brown has a few areas where the paint has been buffed/polished to the point that the primer is slightly visible if you look real close. Those areas show 0.12mm-0.14mm if I remember correctly.(it's a couple of years ago since I checked it) That would indicate that the paint layer(now mostly gone)  is around 0.06mm-0.08mm

Regards,

Hans