POR15 question
Thread Starter
Instructor
Joined: Mar 2002
Posts: 212
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From: Elko New Market MN
POR15 question
The POR15 website states that POR15 is UV sensitive and will turn white, therefore the company recommends overcoating with the chassis paint. When/where does the chassis get exposed to UV to the extent you need to overcoat? Anyone have experience one way or the other? Also, a local body shop was telling me that POR15 cracks and peels in a short time - again any experience?
Le Mans Master
Joined: Jun 2002
Posts: 8,339
Likes: 24
From: I can walk to MA
Re: POR15 question (Bobbyg75)
Hmmmm,
Well, POR only recommends top coating it - and for appearance only.
In the fall, I started to coat the birdcage with POR-15. I ended up with
a bit left over, and I didn't want to throw it away.
I had recently done some under-body resto work on my driver (89 Buick).
There was a large (6") round area on the door, where I had ground away
some rust and bondo. This area was now starting to get surface rust. So,
this is where I put the extra POR. It was outside - in the rain - that night.
I went out, wiped the area wit ha paper towel, and immediately applied
the POR. I never top-coated it.
Over time, I have definitely seen it fade to a yellowish color from the bright
.silver that it started as. I've been driving all winter, and I finally noticed that
there were small rust spots startin gto show through. No cracks. No peels.
I figure the rust started, due to the improper application technique.
I'm using the product on my birdcage and frame. I am top coating with
Krylon semi-flat black. Cheap protection from the unknown, if you ask me.
I top coat a dusting while POR is tacky - then full coats later.
:seeya
Well, POR only recommends top coating it - and for appearance only.
In the fall, I started to coat the birdcage with POR-15. I ended up with
a bit left over, and I didn't want to throw it away.
I had recently done some under-body resto work on my driver (89 Buick).
There was a large (6") round area on the door, where I had ground away
some rust and bondo. This area was now starting to get surface rust. So,
this is where I put the extra POR. It was outside - in the rain - that night.
I went out, wiped the area wit ha paper towel, and immediately applied
the POR. I never top-coated it.
Over time, I have definitely seen it fade to a yellowish color from the bright
.silver that it started as. I've been driving all winter, and I finally noticed that
there were small rust spots startin gto show through. No cracks. No peels.
I figure the rust started, due to the improper application technique.
I'm using the product on my birdcage and frame. I am top coating with
Krylon semi-flat black. Cheap protection from the unknown, if you ask me.
I top coat a dusting while POR is tacky - then full coats later.
:seeya
Senior Member since 1492
Joined: Aug 2000
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Re: POR15 question (Bobbyg75)
I used POR-15 on my front frame & suspension & top coated with gloss Krylon.
I read the bit about it discoloring in sunlight, so of course I had to conduct my own "test". :lol: I applied it to out basketball pole which had a very bad case of surface rust and was constanly exposed to the elements. Well after 2 years the POR-15 is still there in it's glory, fighting UV rays, rain, snow, heat dew etc. No chips or peeling either. I think it's a great product.
I'm gonna try their POR-20 for my used headers. :yesnod:
I read the bit about it discoloring in sunlight, so of course I had to conduct my own "test". :lol: I applied it to out basketball pole which had a very bad case of surface rust and was constanly exposed to the elements. Well after 2 years the POR-15 is still there in it's glory, fighting UV rays, rain, snow, heat dew etc. No chips or peeling either. I think it's a great product.
I'm gonna try their POR-20 for my used headers. :yesnod:
Race Director
Joined: Aug 2000
Posts: 10,854
Likes: 3
From: HONOLULU HAWAII
Re: POR15 question (Bobbyg75)
If you're using it under the car and you keep the rubber sides down....you should not have to worry about UV rays changing the color or deteriorating.....POR-15 is very good stuff.
When I became the Gen Mgr at The Waikiki Landmark....they had a man on the project painting the garage rails and pipes....He could never complete the job..... he'd always have to go back and paint the rails he already painted over again....... within six months the paint was rusting through.....it was the dog chasing his tail.......Several paint companies came out to try their products and none of them were able to keep the rails and pipes from rusting again.....So I tried POR-15 and it never rusted again.....Going on five years now.....My painter is now my Chief Maintenance Man. :seeya Cappy
When I became the Gen Mgr at The Waikiki Landmark....they had a man on the project painting the garage rails and pipes....He could never complete the job..... he'd always have to go back and paint the rails he already painted over again....... within six months the paint was rusting through.....it was the dog chasing his tail.......Several paint companies came out to try their products and none of them were able to keep the rails and pipes from rusting again.....So I tried POR-15 and it never rusted again.....Going on five years now.....My painter is now my Chief Maintenance Man. :seeya Cappy
Melting Slicks
Joined: Mar 2002
Posts: 2,313
Likes: 0
From: The cure for the blues is eight cylinders roaring
Re: POR15 question (8T1-7T9 BIONIC VETTE)
I'm getting ready to do the underside of my car. I only bought 1 qt. of Por15, will this be enough? I'll will be using a brush.
Melting Slicks
Joined: Jul 2001
Posts: 2,609
Likes: 12
From: Massapequa Park NY
Re: POR15 question (PrarieShark)
I used less than a Qt painting top & bottom of the frame, crossmembers, brackets, etc. with two coats by brush. 1 qt should be plenty. Make sure you follow their instructions & wear gloves - that suff will not come off skin once it dries :yesnod:
Melting Slicks
Joined: Mar 2000
Posts: 3,206
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From: WANTED: '68 rear valance with b/u light assemblies IM, e-mail, or PM me here. Thanks!
Re: POR15 question (PrarieShark)
I'm getting ready to do the underside of my car. I only bought 1 qt. of Por15, will this be enough? I'll will be using a brush.
Don't sweat top coating it if it's not going to be in direct sunlight. The chassis of my Cat has no top coat and has been rolled in and out of the garage several times with no signs of discoloration. :thumbs:
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Team Owner
Joined: Jun 2001
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From: Virginia USA
Re: POR15 question (vettery)
Quote. "a local body shop was telling me that POR15 cracks and peels in a short time "
I can't believe that! Not if the instructions are followed.
I can't believe that! Not if the instructions are followed.
Sound like they want to sell you something else. I used POR 15 on my fan shroud and my air cleaner base. This stuff does not peel. I even tried the ball peen hammer test on my shroud and it didn't make even the smallest mark on the stuff. Very tuff. Just follow the directions and wear golves as suggested. I wore some on my finger tip for a few weeks before it wore off. I bought a quart but F'd up and put the top of the can back on without cleaning the top and it glued itself together. I finally got the top off then got smart and placed plastic wrap between the can and the top to keep this from happening again.
POR 15 is Good stuff.
John
Drifting
Joined: May 2001
Posts: 1,329
Likes: 12
Re: POR15 question (Bobbyg75)
A quart will be more than enough to paint a frame. I did mine 6 months ago and took a bit more than half a quart. The guy that said it paints on thick is wrong...if you do that you'll get drippings everywhere. I did 1 lite coat and the 2nd thicker. The frame has been outside in the rain, snow and sun for the past 6 months and there is no signs of peeling, cracking, rusting or discoloring. Actually it looks better than it did before cause this stuff cures with moisture.
Pro
Joined: May 2001
Posts: 608
Likes: 0
Re: POR15 question (Bobbyg75)
I used POR-15 on my engine (I love it)
and I painted the firewall, airbox, underside of hood, and inside fenders with the por-15 semi gloss black.
I did have fisheyes happen on the underside of the hood, 'cause I just couldn't get it clean enough from the stuff the pullies splash up.
There were a couple of areas where the paint flaked off the airbox, and firewall, but I just painted over the old chipped paint, after lightly washing with detergent.
I bought a gallon of POR-15 semi gloss and with it I've painted the engine compartment and the exposed frame therein, the transmission casting, the rear hd diff. cover, the diff. itself, pinion yoke, hd side yokes, driveshafts, axle, trailing arms, steering knuckles, tie rods, sway bar, rear camber rods, radiator core support, ps relay rod, ps cylinder, ps valve, spare tire carrier straps, and still had some left over.
Besides painting over grease and oil, or dirt, the stuff stuck to every other surface, and is going strong now almost 3 years later.
and I painted the firewall, airbox, underside of hood, and inside fenders with the por-15 semi gloss black.
I did have fisheyes happen on the underside of the hood, 'cause I just couldn't get it clean enough from the stuff the pullies splash up.
There were a couple of areas where the paint flaked off the airbox, and firewall, but I just painted over the old chipped paint, after lightly washing with detergent.
I bought a gallon of POR-15 semi gloss and with it I've painted the engine compartment and the exposed frame therein, the transmission casting, the rear hd diff. cover, the diff. itself, pinion yoke, hd side yokes, driveshafts, axle, trailing arms, steering knuckles, tie rods, sway bar, rear camber rods, radiator core support, ps relay rod, ps cylinder, ps valve, spare tire carrier straps, and still had some left over.
Besides painting over grease and oil, or dirt, the stuff stuck to every other surface, and is going strong now almost 3 years later.
