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Best Practices: GTV Surface Rust, Chrome, Floor Pans

3K views 15 replies 7 participants last post by  61SS 
#1 ·
Hi-

I am about to start a bare metal restoration of a 74 GTV. This is my first bare metal project, so wanted to get the wisdom of the BB on a few general things as I scope the first stage of the project:

Very light surface rust – OK to paint over?
This car was blasted & epoxy primed in 2005. After that process the front clip was replaced. When that was done, the inside of the clip was not primed so there is now some light surface rust. Light enough you can sand away a section within 10-15 seconds. Sort of like the rust that will build up on a brake rotor when it sits for a year.

My question: Is it safe to just sand off most of it and paint over the little that might remain? Given it is inside the fenders, nose, and in spot welds, etc. it will be difficult to sand every last bit of the rust away, but I also don’t want to take the car through media blasting again.

If safe to paint over, I assume using a POR product would be best?

Floor pan fix vs. replacement
The PO did a good job of fixing the driver’s side floor pan, but it still needs work to make smooth and seamless. Is it feasible to make a floor repair completely invisible? Or better/easier to just replace the floor pan? I am guessing when the PO did the repairs back on 2005, perhaps replacement floor pans weren't available

Re-chrome bumpers vs. new
I’ve never had anything re-chromed, but will be doing a lot of it with this project. For the bumpers in particular, is it generally better and more cost-effective to re-chrome the existing bumpers (they are straight) or just buy new at $800/ea?

Thanks!
 
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#2 ·
Perhaps this is better posted on the GTV forum?
 
#3 · (Edited)
Very light surface rust

Do not paint over it, and do not use POR crap (IMO). POR is designed for cars that are rusted and actually need metal work but the lazy owners just want to slap some paint on them. I would immediately walk away from a potential purchase if I saw this; last time I looked paints had not developed structural abilities so how people can slap on POR over rusted out metal and feel proud is beyond me.

As you said, takes little time to remove the surface rust, and preparation of the metal is vital to prevent the next restoration being required 2 years from now. You must clean the steel properly and use the right primers to stop the metal sweating.

Floor pan

If the existing repair is not up to your standard and will bug you, yep do it again; or tidy it up

Re-chroming

Your GTV should have stainless steel bumpers and most of the other trim on these cars are also stainless. Just polish and reuse :)

Best
Pete
 
#7 ·
Very light surface rust

Do not paint over it, and do not use POR crap (IMO). POR is designed for cars that are rusted and actually need metal work but the lazy owners just want to slap some paint on them. I would immediately walk away from a potential purchase if I saw this; last time I looked paints had not developed structural abilities so how people can slap on POR over rusted out metal and feel proud is beyond me...
While I agree that you don't want to POR this surface you are wrong that POR is for lazy owners. Used correctly and in the right places it's just another useful tool for restoration work. It is a conversion coating that chemically reacts with the rust. There are plenty of places where you can't get at the rust (think inside surfaces of the frame rails, inner/middle rockers, inner fenders, crossmembers, etc) that are rusting and will continue to rust if not treated. Some folks use POR on rusted suspension pieces - I prefer powdercoat but POR is pretty tough and superior to regular enamel in those areas.

POR can and is used improperly with horrible results but to make a blanket statement that it is crap strikes me as being lazy.

Other than that I agree 100% with everything else that Pete said...
 
#4 ·
Holy moly...I’ve had Alfas off and on since 1985 and I can’t believe I never knew the bright work was stainless. But I’ve had a lot of transaxle cars. Wow...the things one learns.

Any suggestions on “right primers”. I don’t want to leave this to the body shop...want to be educated going in.

Thanks for the reply.
 
#10 ·
Floor pan fix vs. replacement
The PO did a good job of fixing the driver’s side floor pan, but it still needs work to make smooth and seamless. Is it feasible to make a floor repair completely invisible? Or better/easier to just replace the floor pan? I am guessing when the PO did the repairs back on 2005, perhaps replacement floor pans weren't available
There are two ways to weld sheet metal. One is called a lap weld. This is where a patch panel is cut a little on the large size such that it overlaps with the existing sheet metal. This kind of weld is not the best. Also, you'll need to apply filler to hide the repair.

The second type of weld is called a butt weld. This is where the patch panel is cut to fit the the repair area such that it does not overlap the existing sheet metal. It is welded with spot welds to minimize distortion. Once welded, the spot welds are ground down flush such that the repair disappears.
 
#11 ·
The second type of weld is called a butt weld. This is where the patch panel is cut to fit the the repair area such that it does not overlap the existing sheet metal. It is welded with spot welds to minimize distortion. Once welded, the spot welds are ground down flush such that the repair disappears.
I might be off base here, but I disagree with this statement. Butt welding is not spot welding. In my mind, spot welding is with two big electrodes on two overlapping pieces of sheet metal. Similar to rosette welding. Butt welding, is as you mention, when two pieces of metal are place very close end to end and welded together without having a double thick result. This can be accomplished with many methods, MIG, TIG, etc. and can be done one spot at a time or not. Maybe we are talking about the same thing and I just read it wrong.

Cheers,
 
#13 · (Edited)
Yeah, my surface/flash rust situation is inside the front fender. I can get to the vast majority of it, but a few places will be too tight. Given that the car has already been to the media blaster, I don't want to take it again just to get a the very few areas I can't get my hand into.

Sounds like, for these situations, POR (or similar) may be an OK approach. Also, there are a few spot welds that were never primed so also flash rusted a bit. I can likely get to those with a wirebrush, but would want to follow up with a rust inhibitor for extra protection.

On another thread (GT forum) it was suggested for flash/surface rust I could just epoxy prime and move on. True?

Re: the welds, that is really helpful. I think what the PO did was butt welds and it was with a something brass looking (I know little about welding). So will look to see if just grinding down will get it cleaned up sufficiently.

Thanks all...this has been really helpful!

--S
 
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