C3 Birdcage Rust Proofing
Thread Starter
Advanced
Joined: Aug 2016
Posts: 72
Likes: 100
From: Maryland
C3 Birdcage Rust Proofing
Hi, I am about to start work on repairing the rust in my birdcage. What kind of paint / sealers does every recommend for putting on the birdcage after repairs are made ?
Thanks,
Thanks,
Team Owner
Joined: Sep 2006
Posts: 31,274
Likes: 4,366
From: Westminster Maryland
Hi ss,
I realize how much folks like POR 15.
I wouldn't use it on anything I cared about.
POR is short for Paint Over Rust.
Regards,
Alan
Here's the description from the POR15 site.
"POR-15® Rust Preventive Coating is a high-tech, high performance rust-preventive coating designed for application directly on rusted or seasoned metal surfaces."
I realize how much folks like POR 15.
I wouldn't use it on anything I cared about.
POR is short for Paint Over Rust.
Regards,
Alan
Here's the description from the POR15 site.
"POR-15® Rust Preventive Coating is a high-tech, high performance rust-preventive coating designed for application directly on rusted or seasoned metal surfaces."
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
Depends on the level of restoration, urgency, expense you are willing to go to. POR is a quick and comparatively inexpensive option. On a serious restoration I personally think that full removal of rust is the best way to go. Then use a high quality primer, several are out there, I like some of the Eastwood products.
Here is a case where I used POR15. I was restoring a 1972 El Camino and I was trying to do a good but fast job to get it decent but on the road quickly. This car was generally solid but had a few areas of rust. The worst being the radiator support, especially at the bottom. I scrapped and brushed that area, cleaned it with lacquer thinner, then gave it a good heavy coat of brushed on POR. I kept that car/truck for over 20 years. Shortly before I sold it I was changing out the radiator and when I cleaned out the radiator support I wiped it out real good so I could see how it held up. That POR looked exactly like it did the day I put it in there 20 years before. It DOES have its place. You just need to decide when and where for your own objectives.
Here is a case where I used POR15. I was restoring a 1972 El Camino and I was trying to do a good but fast job to get it decent but on the road quickly. This car was generally solid but had a few areas of rust. The worst being the radiator support, especially at the bottom. I scrapped and brushed that area, cleaned it with lacquer thinner, then gave it a good heavy coat of brushed on POR. I kept that car/truck for over 20 years. Shortly before I sold it I was changing out the radiator and when I cleaned out the radiator support I wiped it out real good so I could see how it held up. That POR looked exactly like it did the day I put it in there 20 years before. It DOES have its place. You just need to decide when and where for your own objectives.
Last edited by 68/BB; Oct 10, 2017 at 10:27 AM.
Pro
Joined: Jul 2006
Posts: 505
Likes: 25
From: Buxton Maine
I have never understood why POR15 is so well liked. Imo it's messy and ugly. It's purpose is painting over and encapsulating rust. Pity the next guy who has to try and remove it to do a proper job. I'd consider using it on an old junk plow truck and that's about it. I do not believe it has any place in a restoration. Especially a Corvette restoration. Sorry if this offends some but Imo it's awful stuff.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
I sandblasted and sprayed every metal surface under the car, suspension around 2000 still looks like it was done yesterday, it will never rust in my lifetime so it was worth it to me. You have to follow directions to a T or youll be doing it again thats where most of the " I hate this stuff" comes from. Its not something you want to try and remove thats for sure.
First time around I shortcutted prep & did a 12 bolt;sure enough it reacted and started to bubble.
I had to take it in and have it sandblasted as mine wouldnt cut it guy was pretty p/o'd saying it "was powdercoated" lol.
Theres stuff out today thats easier and cheaper to use...rattle can never holds up too long esp if you drive it.
the neat thing about por is you never have to wash it, everything simple wipes off with a rag nothing sticks to it
First time around I shortcutted prep & did a 12 bolt;sure enough it reacted and started to bubble.
I had to take it in and have it sandblasted as mine wouldnt cut it guy was pretty p/o'd saying it "was powdercoated" lol.
Theres stuff out today thats easier and cheaper to use...rattle can never holds up too long esp if you drive it.
the neat thing about por is you never have to wash it, everything simple wipes off with a rag nothing sticks to it
Last edited by cv67; Oct 10, 2017 at 11:28 AM.
Thread Starter
Advanced
Joined: Aug 2016
Posts: 72
Likes: 100
From: Maryland
Thanks everyone for you suggestions. My goal is to the best job in preventing rust from growing. I do plan to cut out any rust and replace with new metal But it looks like POR-15 is the way to go.
Thank you all !
Thank you all !
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Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Don't forget to coat the inside of the frame as well, rust attacks from within also. I used a fish oil based product and a shop gun to blast it through every hollow section of the frame including the bridge part of the birdcage (the bit between the top of the windscreen and the back support of the birdcage) Condensation can rust out this section from the inside.
Race Director
Joined: Jan 2002
Posts: 11,615
Likes: 350
From: No Where USA
I have never understood why POR15 is so well liked. Imo it's messy and ugly. It's purpose is painting over and encapsulating rust. Pity the next guy who has to try and remove it to do a proper job. I'd consider using it on an old junk plow truck and that's about it. I do not believe it has any place in a restoration. Especially a Corvette restoration. Sorry if this offends some but Imo it's awful stuff.
Don't use it. Do the job properly and get the rust off the parts then epoxy.
Burning Brakes
Joined: May 2004
Posts: 996
Likes: 13
From: Dallas TX
Team Owner
Joined: Sep 2006
Posts: 31,274
Likes: 4,366
From: Westminster Maryland
Hi B04V,
In areas I was concerned about controlling rust in I would use zinc chromate primer.
Primers with zinc chromate in them are no longer readily available to the public because zinc chromate is known to be carcinogenic.
Many of the primers are just enamel mixed to look like the greenish yellow that zinc chromate primers typically are.
Actual zinc chromate primer is available from suppliers to the aviation industry.
Regards,
Alan
In areas I was concerned about controlling rust in I would use zinc chromate primer.
Primers with zinc chromate in them are no longer readily available to the public because zinc chromate is known to be carcinogenic.
Many of the primers are just enamel mixed to look like the greenish yellow that zinc chromate primers typically are.
Actual zinc chromate primer is available from suppliers to the aviation industry.
Regards,
Alan
Pro
Joined: Nov 2016
Posts: 729
Likes: 118
From: Kelowna British Columbia
IMHO the use of POR15 is not for shortcuts like painting over rust. That would be crazy. Rust has to be removed first whether with a abrasive disc, wheel, grinder and scraper. Once cleaner up properly it should be treated as rust is like a cancer. If you don't cut it out and replace it will comeback hence the suggestion of POR to slow its spread.
Team Owner
Joined: Sep 2006
Posts: 31,274
Likes: 4,366
From: Westminster Maryland
Hi ss,
After looking at the other thread you just started I'd say yes, sandblasting (or blasting with media of some sort), would be a good way to clean the cage so you can see exactly what you have to work with.
There are folks that have done the type of work you're getting ready to begin and I'm sure they can offer you more specific advice than I can about removing parts of the rear clip (the lock pillar cover), and the rocker channel cover.
Have you been looking through your Assembly Manual? There is SOME some useful information concerning how the cowl and rear clip were attached/bonded to the cage. Look in UPC 1, on the A & B sheets.
Regards,
Alan
After looking at the other thread you just started I'd say yes, sandblasting (or blasting with media of some sort), would be a good way to clean the cage so you can see exactly what you have to work with.
There are folks that have done the type of work you're getting ready to begin and I'm sure they can offer you more specific advice than I can about removing parts of the rear clip (the lock pillar cover), and the rocker channel cover.
Have you been looking through your Assembly Manual? There is SOME some useful information concerning how the cowl and rear clip were attached/bonded to the cage. Look in UPC 1, on the A & B sheets.
Regards,
Alan
Last edited by Alan 71; Oct 11, 2017 at 11:21 AM.
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
alot of times buyers see por15 they think it was painted over rust. take plenty of pics to prove that is not the case. you need to show that your birdcage is totally rust free and if you are dissassembleing that much you owe it to yourself to do a complete 100% repair.
birdcage rust is a result of windshield seals failing from water.
I expect that your philpsophy after your restoration will be to minimize your time in the rain and snow and salt anyway so most likely anything you coat the birdcace frame with will last 100 years... if you remove all the existing rust.
POR15/paint/other epoxy sealers will all do fine if there is no water/salt accelerant. but you have to get the stuff in and around everything to do a complete job.
nothing will give you that 100 year window unless you get it all thruout the inside also.
birdcage rust is a result of windshield seals failing from water.
I expect that your philpsophy after your restoration will be to minimize your time in the rain and snow and salt anyway so most likely anything you coat the birdcace frame with will last 100 years... if you remove all the existing rust.
POR15/paint/other epoxy sealers will all do fine if there is no water/salt accelerant. but you have to get the stuff in and around everything to do a complete job.
nothing will give you that 100 year window unless you get it all thruout the inside also.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
IMHO the use of POR15 is not for shortcuts like painting over rust. That would be crazy. Rust has to be removed first whether with a abrasive disc, wheel, grinder and scraper. Once cleaner up properly it should be treated as rust is like a cancer. If you don't cut it out and replace it will comeback hence the suggestion of POR to slow its spread.
painting over it imo is a waste, its still there and will spread
you can tell when someone has, either the surface or finish is smooth or it isnt. Seeing a frame off where its obvious someone painted over rust, road grime is useless, may help them flip it quicker to someone that doesnt know any better.