Seam Sealer and Dum-Dum: Factory correct details

[jneely]

Seeking photos of original cars; old pictures or unmolested original cars (w/original paint). Looking for factory-correct application of seam sealer, particularly around the trunk opening.
I 'think' that the seam sealer on the lip around the trunk opening was applied before paint, but my car had been repainted, and having trouble finding a good original reference photo.

From what I can tell:
Black brush-on seam sealer was used on all joints in the interior, underhood and trunk panels, and appears to have been applied after paint. Earlier '52 cars did not have this in all locations indicated in the shop manual. Service Bulletin 52-9 defines this as 'paste type sealer', Presstite No. 322.4

From what I can tell dum-dum coating sprayed on trunk floor, passenger floor, doors and inside roof were applied prior to primer. There is primer overspray on the edges, and paint color over top. Dum-dum on the bottom of car, though, in the rear wheel liners, is done after paint. Dum-dum is black with paint color underneath. The sheet metal wheel well inserts were black, regardless of body color, and installed prior to dum-dum application.

[MarkH]

I've got hundreds of disassembly photos of two cars and unfortunately both cars were too dirty or rusty to tell what was layered on what in the photos.
I think you're right about the trunk opening though, seems I'd remember black sealant on top of the paint there.

The painter used Sem sealant (pictured) to smooth all the under hood seams as well as the ones that called for sealing. Also on the roof gutter seam. It painted beautifully.

I had done some internet searches for Presstite sealant and followed a trail of corporate owners/mergers and the closest I came up with is the sealant cords pictured. I was mainly interested in duplicating the sealant in the fender to wheelhouse/body & fender to grill shell seams at the time.
It's not as gray as the 60yr old stuff that was in those seams but seems to be a similar non hardening putty-like sealer. There were also dried & cracked remains in the roof gutter.
I ended up opting to not seal those seams with the putty strips but I did use it (3 strips each) on the panels the rear window regulators fasten to, and to seal the grommet holes in the firewall.
I found very similar sealant IN the roof stamping to rail joint as well at the "T" joint at the rear fender to body joint, except that sealant had a small string imbedded in it. Crazy as it sounds, it appeared to be in the joint, then spot welded together.
I don't think the new putty or the 60yr old version I found could take a lasting bond to paint.
It almost reads to me like there were different versions of "Presstite" called for on different parts of the body too.

I would definitely go with the Sem or some similar modern paintable body sealant for the gutter rail

EDIT I filled the voids in the under sides of the trunk hinges with clear silicone so they would apply even pressure to the gaskets. Gaskets migrating into those voids as they aged was an issue. I skipped Presstite in the mounting bolt cups.

[Thomasso]

My 55 is original paint.  The sealer around the trunk opening is painted body color.  the sealer in the troth ,inner wheel well to floor is not painted but seems to be a grey color.  I'll try to post some pictures.

[jneely]

Excellent - thank you both. I found a reference to paint process in the 54 Fact Book that confirms the gutters were seam sealed prior to paint, and looks like the trunk opening may have been done at the same point. I will hit it prior to paint.

I like LORD Fusor seam sealer. Started using it after reading this article. I plan to use it for everything, using the after-brush technique to make it look like brush-on type for the locations done after paint.
https://www.hotrod.com/articles/resto-tech-apply-seam-sealer-correctly/

Note that the earlier cars definitely have black sealer over the paint, as in the area shown in Thomasso's lower inner trunk lip. Must have been a running change to the lighter color shown.

[jneely]

Progress photos- seam sealer on the roof and trunk opening gutters. Also did the trunk floor perimeter prior to sound deadener application. I'm happy with how it turned out - not as thick as original but it has the right look and texture.

[MarkH]

Looks good!
By the way, restoration Specialties had all my rubber plugs & grommets. Heating them in a pan of hot water temporarily softens them for installation.