GuitarMike

Hi,
I'm going to finish getting the scale and loose stuff off my frame, and would like to coat it with POR-15. Not doing the full breakdown, but will be coating everything I can get at. I have a new (junkyard) center crossmember to replace the current (rotted) one; hit it with a wire brush on the angle grinder, and coated it with POR. It seems to be drying up really nice, 4 hrs later!! This is how I'd like to get the rest of the truck.

Question: a lot of people talk about 'marine clean' and other tricks to prep the frame prior to using POR. Is it 'good enough', in the experience of those who've done this, to just wire brush the rust well, wipe the dust down, and hit the dry frame with POR? I'd think any salt or other crap that would interfere would be gone from that prep. This isn't a brand-new ride; I would like to get it done as quickly as possible, given the several hours I already have into pounding scale off, LOL!
Thanks for whatever input you guys have. Great forum; learning tons on here!

Zack1983

I have always got as much stuff off as possible, degrease with simple green aircraft degreaser, rinse and let dry, then spray on por 15 prep and ready, rinse, let dry and then apply the por 15. I have no idea what would happen if you did something else. I figured that I may as well take the time to do it thoroughly and it has always yielded great results for me.

So I have no experience in just putting the por 15 on an unprepared surface, so I would be curious to see if any has and what their results are. It does take a while to do it the way I have done, but I am always working on other stuff while things dry, so no big deal. I figure if you plan on having the truck long enough to make it worth wild to spend the time and money on por 15, you may as well take the time to make sure that it will last.

4Crawler

iTrader: (3)

If the metal is pretty rough or has some good rust pitting, POR-15 will still very well. That is how I did my rear bumper, let it surface rust for a couple of years then POR-16 and you can pound on that coating hard with a hammer and nothing happens to it. If there is shiny metal, then the Marine Clean/Metal Ready (etch) works well. Short of that, hit the bare steel with some CLR or LimeAway (same phosphoric acid at the Metal Ready uses) and keep it wet for 1/2 - 1 hour then sit overnight and it'll flash over with a yellow/red surface coating.

paintthetown

iTrader: (1)

I just finished the under side of my rusty 87 Runner. I did the 3 steps. I ran the Marine Clean through my pressure washer (truck was jacked up). All I could say was damn I didn't know there was so much dirt and grease. WOW, it looked great. After it dried you could see even more rust was hiding under the grease. The prep and ready just prep the rust for paint, any phosphate coating will do. Spraying will look the best. I got a little on my hand and it would not come off for several days (gloves). The stuff is sweet and is hard as nails. Note: I'm not a rep for Por-15 a good friend turned me on to them. Good luck

GuitarMike

Thx. I like the CLR idea....don't have access to a pressure washer and the stuff I'd need to run liquids thru it (well, I can rent one as I do for work, for $65/day - bleh!). Nor the $ for another pricey product!

So far, the cross member is great - wirebrushed, dusted off, and applied. It was pretty rusty but just beginning to scale; perfect for how the advertise POR! It is now rock hard; no way the stuff is coming off!
If you apply the CLR, you just hit it and let it sit, no rinsing?
This stuff is amazing...it LIKES water and rust! I am a painter; never came across a product that lives in that environment! Imagine this stuff on cast iron railings, etc.....wow!

paintthetown

iTrader: (1)

Mike, I'm a painter as well in Florida. Rinse, rinse, rinse before you apply por15. All must be completely dry before applying top coat. Wait, your a painter with no pressure washer ? What? JK man good luck

GuitarMike

LOL, I still rent them. We don't get as much mold etc. here in New England as you might down there....a lot of peeling, old, lead paint! Do a lot of stain work, which doesn't require the washing (people are cheap up here, too!). Someday I'll buy one....

OK, cool - I'll CLR any bare metal that might show up when I use the wire wheel (fat chance THAT'LL happen, ha ha), go 24 hrs, then rinse the crap out of it and let dry. THAT should do it!

Judging by the new crossmember I did yesterday, the stuff isn't THAT picky, altho it would need road abuse to know for sure (salt, water, gravel, sand bouncing off it, etc).

Is anybody actually hitting the POR with a real topcoat, or just leave it be? It's under the truck so it shouldn't get any real UV light....

4Crawler

iTrader: (3)

When I use CLR or the POR-15 Metal Ready, I think the instructions way to keep the surface wet for 30-60 mins. then rinse and dry. I usually use a scrubbing pad to go over the surface as I rinse. Then primer and top coat. I find the primer drying time is highly influenced by the weather conditions. High humidity makes it dry faster and in hot, dry weather it sometimes will stay tacky for hours, really strange stuff. For the top coat, you can either put the first coat on when the primer is just barely dry, while there is just a little drag as you rub a finger over it. Or you can wait for it to fully cure then light sand and top coat.

GuitarMike

Thanks all!