Author Topic: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?  (Read 5443 times)

Offline drummingrocks

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Hi guys, I've been thinking for a while about stripping and repainting my '67 coupe.  I know the car will need one and possibly both quarters.  That being said, I'm trying to save as much original sheet metal as possible.  Both the hood and decklid have the typical rust around the seams, as well as on the backside areas where paint couldn't get into when the parts were painted at the factory.  After 45+ years, some of those areas are starting to rust from the inside out.  The decklid it starting to bubble around the Mustang trunk letters, as they tend to do.

I was wondering if it was worth trying to save these parts?  I'd like to save them if possible, but I hate to paint the car and have these areas bubble a few years down the road.  I thought about using something like Eastwood Internal Frame Coating (http://www.eastwood.com/internal-frame-coating-aerosol-black-14oz.html), but I wasn't sure if I could realistically access some of these areas. I worry especially about getting to the backside of the Mustang trunk letters on the decklid; that's the area where most decklids seem to rust.  The hood should be fairly easy to access, using the holes for the hood striker.

Any advice is appreciated!   :D
Too much junk, too little time.

Offline Bob Gaines

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #1 on: January 16, 2015, 02:12:27 PM »
Hi guys, I've been thinking for a while about stripping and repainting my '67 coupe.  I know the car will need one and possibly both quarters.  That being said, I'm trying to save as much original sheet metal as possible.  Both the hood and decklid have the typical rust around the seams, as well as on the backside areas where paint couldn't get into when the parts were painted at the factory.  After 45+ years, some of those areas are starting to rust from the inside out.  The decklid it starting to bubble around the Mustang trunk letters, as they tend to do.

I was wondering if it was worth trying to save these parts?  I'd like to save them if possible, but I hate to paint the car and have these areas bubble a few years down the road.  I thought about using something like Eastwood Internal Frame Coating (http://www.eastwood.com/internal-frame-coating-aerosol-black-14oz.html), but I wasn't sure if I could realistically access some of these areas. I worry especially about getting to the backside of the Mustang trunk letters on the decklid; that's the area where most decklids seem to rust.  The hood should be fairly easy to access, using the holes for the hood striker.

Any advice is appreciated!   :D
The eastwood stuff comes with a extension tube to apply the product in tight area plus it will ooze down in seems before it starts to solidify into a waxy consistency hours later definitely a consideration  for long term protection.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline 67gtasanjose

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #2 on: January 16, 2015, 03:34:53 PM »
The eastwood stuff comes with a extension tube to apply the product in tight area plus it will ooze down in seems before it starts to solidify into a waxy consistency hours later definitely a consideration  for long term protection.

I was thinking of this product too for various areas. Areas I cannot get with this other method below:

The other method an old-timer Body man showed me and I have used it on an old Regal door that basically needed replaced. His method was to remove all the rust possible by whatever means required. My 85 Regal door skin lower edge was basically rusted off so I cut open what was there by rolling back the edges of the door skin. Removed all the rust by chipping, grinding, sandblasting and then I sectioned in a lower door skin edge. Just before rolling down the door skin, I brushed FIBERGLASS RESIN in the overlap and rolled/tamped it down while it was curing (you have to work fast) Then I mixed more resin up and poured down into the bottom channel and tipped the door back/forth to spread it around, thow-away paint brush helps in spreading it too. GRAVITY is your friend, rolling the door around, the resin flows like water, deep into the crevices.  (obviously, the door is off the car)  Cleaned what comes out the door drain holes with lacquer thinner & let it cure. Mix more resin and did the front edge of the door, let cure, mixed more and did the back edge of the door. Normal, thin bead of body sealer at the edge of the door skin when resin was all cured. Sand, Prime & Paint

That was in 2005 and 10 years later, the "Daily Driver", not driven in winter car, that door is just as solid as day 1.

Richard
« Last Edit: January 16, 2015, 03:38:24 PM by 67gtasanjose »
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments

Offline cobrajetchris

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #3 on: January 16, 2015, 11:09:45 PM »
My philosophy on rust is repair by replace however there are panels that are good candidates for repair such as lower patch panels on quarter panels where there will be access to repair or section  the adjacent trunk drop off or wheelhouse. A lower fender patch would be another good example, however when you are dealing with a hem flange that is rusted this is a very tough permanent repair. The only way to get rid of the rust completely is to grind off the outer panel up to the point were there is no rust and make a patch or buy a patch panel if available. The patch would have to be welded in the section area and the flange folded over the shell. This is not easy to get right and you will lose the factory spot welds. If it was my car I would find a rust free trunk lid from the southwest. Then I would blow all the drain holes clean and apply the corrosion protection of your choice. The hood will be more of a challenge to find then a coupe trunk lid but you are dealing with the same kind of problem if rust is coming through the outer panel. I have had some luck in repairing the front edge of the hood shell and just clean up the outer panel once the rusted area is removed. The inner shell is a little more forgiving to weld. The problem with gambling with this kind of rust repair is not only the labor but the material cost to repair and paint is a fortune.
CHRIS KNOBBE
69 MUSTANG COUPE, DEARBORN BUILT 06/10/69 OWNED SINCE 1978
70 BOSS 302 MUSTANG, DEARBORN BUILT 10/24/69 OWNED SINCE 1987
69 R CODE MACH1 AUTO, DEARBORN BUILT 10/10/68 OWNED SINCE 2006
69 R CODE MACH1 4 SPEED (factory black) SAN JOSE BUILT 12/30/68 OWNED SINCE 2007

Offline 1969 Cale II

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #4 on: January 17, 2015, 05:23:15 PM »
As said before, the best repair is a rustfree panel. You never know when the next rust bubble will come up. If you want to repair it, after you are done patching the holes, run POR 15 on the inside. Use gravity( somebody said that already). This stuff is pretty thin and dries hard as a rock. I used this trick to protect panels for the future. I did the decklid, doors, hood and quarters. Be sure to clean the runs as it comes out drain holes, seams etc.

Offline Bob Gaines

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #5 on: January 17, 2015, 11:22:12 PM »
As said before, the best repair is a rustfree panel. You never know when the next rust bubble will come up. If you want to repair it, after you are done patching the holes, run POR 15 on the inside. Use gravity( somebody said that already). This stuff is pretty thin and dries hard as a rock. I used this trick to protect panels for the future. I did the decklid, doors, hood and quarters. Be sure to clean the runs as it comes out drain holes, seams etc.
+1 . The other techniques talked about as well as some others not mentioned yet will just slow the rust process down to a crawl . It might take years to show back up again. The only way to stop it is to eliminate it with new metal or metal that has had rust blasted completely away .The bare metal can be treated with techniques like those mentioned so it will not start to rust to begin with.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline 67gtasanjose

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #6 on: January 18, 2015, 07:53:38 AM »
ZERO percent moisture also stops rust in it's tracks, but not everybody puts their car in a museum with climate control of 0% humidity...just saying.
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments

Offline Bob Gaines

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #7 on: January 18, 2015, 11:38:35 PM »
ZERO percent moisture also stops rust in it's tracks, but not everybody puts their car in a museum with climate control of 0% humidity...just saying.
+1 . That is what the products being discussed do . They insulate the surface from moisture.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline drummingrocks

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Re: Rust Repair--Treating the Inside/Underside of Hoods and Decklids?
« Reply #8 on: January 20, 2015, 10:22:47 AM »
Thanks, guys.  Sounds like we're on the same page.  If some of the products mentioned keep the rust from coming back for even a few years, I'll be happy.  The car in question is something of a driver, so it's going to be in all kinds of moisture and inclement weather.  I really can't justify putting super nice sheetmetal on it; I'd rather those kind of parts be preserved for others that really need them for their restorations.  This is just a nice driver.
Too much junk, too little time.