Author Topic: Will primer last for a year w/o damaging the metal?  (Read 2698 times)

Offline EMCD

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Will primer last for a year w/o damaging the metal?
« on: January 03, 2013 - 05:55:57 PM »
i'm breaking up the restoration of my cuda and was wondering if i could leave the car in primer and drive it for a 6-12 months before painting it. Will this work? I won't be driving it in the rain. What are some things to consider for this option?




Offline 'Cuda Hunter

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Re: Will primer last for a year w/o damaging the metal?
« Reply #1 on: January 03, 2013 - 08:04:36 PM »
I do believe it would need to be a few layers of primer so you can sand off the exterior layer.
Bugs and road grime would be bad to have under the new paint.

Seems lots of guys like to drive around with a guide coat on.  Should be fine.
I'd try to stay off of the Magnesium Chloride they put down here.
That would be a nightmare.  It gets everywhere. 

Still better than straight salt.

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Offline Cuda Cody

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Re: Will primer last for a year w/o damaging the metal?
« Reply #2 on: January 03, 2013 - 09:50:48 PM »
Personally I would not do it.  Primers do not protect the same and epoxies can break down in UV light.
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Offline 72bluNblu

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Re: Will primer last for a year w/o damaging the metal?
« Reply #3 on: January 04, 2013 - 12:48:18 AM »
Primer is the sealer for your paint, that's what its for, and it does a better job of sealing than the topcoat does. So, for protecting the metal it'll be fine as long as you put down a good, solid coat of primer (or two, or more depending on your primer).

But, it doesn't hold up to UV light, so it will deteriorate if it's outside on its own too long. And then there's the contamination issue. Topcoat is more susceptible to contaminants than primer, and if you've been driving your primered car around for awhile it will be covered in contaminants, which kinda defeats the purpose of the primer.

Not saying you can't do it, but you'll have some extra work. Short term, it'll need a serious bath (think dish soap, no waxes), then a wipe down with wax and grease remover. Long term, you'll need to do that, then consider another coat of primer. If the primer has started to break down it won't do it's job, and the longer it's on there the harder it'll be to clean, so a fresh coat of primer will help ensure your topcoat actually sticks and comes out contaminant free.
« Last Edit: January 04, 2013 - 12:50:54 AM by 72bluNblu »

Offline EMCD

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Re: Will primer last for a year w/o damaging the metal?
« Reply #4 on: January 04, 2013 - 08:38:32 AM »
Makes sense to just wait and do it all at once. I'll do the front end conversion to the 71 and wait until next winter to do the rest of the body. Thanks for the feedback.

Offline torredcuda

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Re: Will primer last for a year w/o damaging the metal?
« Reply #5 on: January 04, 2013 - 08:10:52 PM »
Primer is the sealer for your paint, that's what its for, and it does a better job of sealing than the topcoat does. So, for protecting the metal it'll be fine as long as you put down a good, solid coat of primer (or two, or more depending on your primer).

But, it doesn't hold up to UV light, so it will deteriorate if it's outside on its own too long. And then there's the contamination issue. Topcoat is more susceptible to contaminants than primer, and if you've been driving your primered car around for awhile it will be covered in contaminants, which kinda defeats the purpose of the primer.

Not saying you can't do it, but you'll have some extra work. Short term, it'll need a serious bath (think dish soap, no waxes), then a wipe down with wax and grease remover. Long term, you'll need to do that, then consider another coat of primer. If the primer has started to break down it won't do it's job, and the longer it's on there the harder it'll be to clean, so a fresh coat of primer will help ensure your topcoat actually sticks and comes out contaminant free.

Not true,some primers will not seal or protect your metal from miosture and it will rust out right thru the primer.Epoxies do make a good barrier and can actually be used as a sealer but it will still deteriorate.
Jeff
72 Barracuda 340/4spd  Torred
70 roadrunner 383/auto  In-Violet
70 Duster 360/auto drag car  (Petty Blue soon)
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Offline 72bluNblu

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Re: Will primer last for a year w/o damaging the metal?
« Reply #6 on: January 04, 2013 - 08:46:21 PM »
Not true,some primers will not seal or protect your metal from miosture and it will rust out right thru the primer.Epoxies do make a good barrier and can actually be used as a sealer but it will still deteriorate.

Then don't use crappy primer.  :icon16: Topcoat is also porous, so if you're not using a primer/sealer then you're not doing yourself any favors.

I assumed that the OP knew to use a sealer/primer before using a sanding primer. And I believe I made the point that even then the primer would deteriorate with UV exposure. On the other hand, I have a '53 Dodge truck that I primered with PPG-DP90 to keep if from rusting as it sat outside that's been parked for over 10 years. Primer's still doing its job just fine, although I wouldn't shoot topcoat over that either.

Offline 72cudamaan

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Re: Will primer last for a year w/o damaging the metal?
« Reply #7 on: January 04, 2013 - 11:48:54 PM »
Primers absorb moisture, period. If not sealed with a finish coat, they will break down over time. Sure Dp40.50 and the others
hold up, but over time they too will not be a good base for color. And the OP said he wants to drive it. I couldn't in good conscious tell
him it's Okay to do that.
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Offline torredcuda

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Re: Will primer last for a year w/o damaging the metal?
« Reply #8 on: January 05, 2013 - 09:09:18 AM »
Then don't use crappy primer.  :icon16: Topcoat is also porous, so if you're not using a primer/sealer then you're not doing yourself any favors.

I assumed that the OP knew to use a sealer/primer before using a sanding primer. And I believe I made the point that even then the primer would deteriorate with UV exposure. On the other hand, I have a '53 Dodge truck that I primered with PPG-DP90 to keep if from rusting as it sat outside that's been parked for over 10 years. Primer's still doing its job just fine, although I wouldn't shoot topcoat over that either.

 :iagree:  I just wanted to clarify things so someone doesn`t ruin their car.You know what happens when we assume!  :22yikes:
Jeff
72 Barracuda 340/4spd  Torred
70 roadrunner 383/auto  In-Violet
70 Duster 360/auto drag car  (Petty Blue soon)
04 Ram 2500 5.7 Hemi

Offline DocMel

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Re: Will primer last for a year w/o damaging the metal?
« Reply #9 on: January 07, 2013 - 10:52:24 AM »
NO   auto grade primer tends to asorb small amounts of moisture if not sealed over with time.  Also, any grease, oil, (think pavement) silicone, dirt, etc over time will become absorbed into the primer coat, and will react to paint applied.   Bare primer is just a temp protectorant when not painted over

Offline EMCD

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Re: Will primer last for a year w/o damaging the metal?
« Reply #10 on: January 07, 2013 - 12:54:29 PM »
Thanks for all the advice. So, it looks like I'll be doing the body and paint all at once. I'm going to replace the qtrs with skins, outer wheel wells, trunk extensions, pulling dings and primer/ paint. How long would this take a two person team of autobody techs? 4 months?

Offline elitecustombody

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Re: Will primer last for a year w/o damaging the metal?
« Reply #11 on: January 10, 2013 - 01:58:59 PM »
Not true,some primers will not seal or protect your metal from miosture and it will rust out right thru the primer.Epoxies do make a good barrier and can actually be used as a sealer but it will still deteriorate.

 :iagree:
Stefan B

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Offline 73restomod

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Re: Will primer last for a year w/o damaging the metal?
« Reply #12 on: January 11, 2013 - 02:48:17 AM »
Anything over 6 months even in storage is risky, thats what I was taught anyway.

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Offline 'Cuda Hunter

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Re: Will primer last for a year w/o damaging the metal?
« Reply #13 on: January 11, 2013 - 04:16:16 PM »
Am I a redneck or what?

Sorry for the poor advice.  I knew I shouldn't have said anything.   :banghead:
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Offline Cuda Cody

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Re: Will primer last for a year w/o damaging the metal?
« Reply #14 on: January 11, 2013 - 06:36:51 PM »
It's a fact that none of us here know everything, but between the collective group we can usually give pretty good advice.  Don't sweat this one man, you normally give real good advice.  Also, I don't think you were wrong, just not a right as you normally are.   ;)

Am I a redneck or what?

Sorry for the poor advice.  I knew I shouldn't have said anything.   :banghead:
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