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Just a quick question.
I was thinking of using por 15 on my steel before I cut it and even though I would have to clean it off my weld joints everything else would be coated.
Good idea or bad idea? What do you think?

I think it would be a waist of time to por 15 it first. That is my I haven't built a locost opinion though, if that is a factor to dismiss. I think a quick wire brush and some good weld through primer after cut and fit would be worth it though. My thought on that is primer isnt the best to stop rust but its better than bare steel. Then with a quick wash maybe a scuff then a wash it is ready for paint. It will look better with out the sand back and touch up. Also it will be a easier and cleaner process that dose not involve acid.

I think it's a good idea to paint the frame grey. That way you can see cracks at the joints. Black makes it look like a blacksmith job...

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I've used POR 15 and won't anymore.

Wipe the steel down with acetone and a rag when you get it and use rustoleum spray cans (another vote for light grey) with the little yellow "stops rust" label on the can. Home Depot is a good place for a wide selection of Rustoleum products.

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If the frame will be powder-coated, don't worry about it; the businesses first media-blast the metal, so any surface rust is a non-issue.

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Cut, weld, then paint. The rust won't get that bad. If you insist on keeping the rust at bay, clean the frame tubes every few days with a 3M finishing pad.

POR-15 isn't really a good coating for clean metal anyway.

I am purposefully leaving the mill oil on the steel of my frame until it is ready for paint. My garage stays quite a bit humid - To the point where many of my impact sockets have surface rust on them LOL.

Once I am ready for paint, I'll wipe the whole thing down with pre kleano, then a day or two later - paint it.

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Tucker

Thank you all very much for the good advice. That's kind of what I thought but wanted some opinions. I doubt if powder coating is in the budget and I doubt if this project will ever be 100% completed anyway. Modifications are part of the fun.

I used POR 15 TopCoat for my CB750 frame a couple years ago, and it worked great. It is NOT the same as the POR 15 Rust Preventative that was available for years.

TopCoat can be used on bare metal or over POR 15 Rust Preventative. My motorcycle frame was bare metal and I have had no issues with the TopCoat. They offer it in several colors now as well. I plan to use it on the Seven also, and it can be rattle-canned or brushed on (I bought a quart and a few spray cans for this job, and I still don't know which will be better). It takes a while to set, but once it has hardened, it seems pretty tough.

I know Eastwood makes a 2K chassis coat as well, which I considered. It's a bit more $ though. I figured I can always reapply if absolutely necessary.

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I used POR-15 to fix my pickup where the paint has basically been sandblasted by driving on dirt roads and it was starting to rust. I don't think it's as durable as it's billed as. It's already come off the rocker panel where I normally tap my boots to knock the mud off, and that's not even close to the abuse that the fenders get from gravel. It's probably great stuff in low wear applications, but I think in the future I'm going to go with the Endura two part stuff my brother likes for his farm projects. That stuff is truly tough.
Kristian

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I replaced a couple fenders on a car trailer a long time ago. There was a gap of about 2 months when I couldn't get around to installing the second fender but the first was on and sitting out in the driveway with no paint.

When I painted the trailer (rustoleum bare metal primer, then topcoat black) one fender started the process looking absolutely brand new and the other one had a nice, even coat of surface rust. I scrubbed the new fender with acetone and pre-heated it with a torch to pull any oil/moisture out, then more acetone cleaning, it was a nice surface. I just blew the rusty fender off with an air hose figuring all was lost anyway.

That new fender threw paint off itself the entire time I owned the trailer, never once stuck even a little bit no matter what I did. The light surface rust fender looked brand new for at least 4 winters, not even a chip.

Moral of the story is that a little surface rust won't hurt a thing and is way preferable to having to sand back paint every time you weld. Trust me, that's going to start to suck a LOT about 3/4 through the project when you're trying to move a bit faster and every single job starts with 2 minutes of smelly, dirty sanding.

Alex

Plus you are supporting a real dyed in the wool car guy.

Google "Jay Esterer" - owner/operator of Endura. Not often I get to vouch for local talent on here.