Mower Deck Coating

Evil Spirit

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Rebuilding the deck on one of my lawn assault vehicles and looking for options to coat the underside of the deck. Not really wanting to spend the coin to get the deck blasted and powder coated. So what's a good Plan B? Surface prep will probably be a good scraping and wire wheeling, with a chemical prep if necessary. So I'm looking for proven suggestions for an aerosol can or a brush on coating that inhibits rust and hopefully discourages grass build-up. Right now I'm considering POR-15 or Rustoleum Rust Stop enamel, or both. Any suggestions? Thanks, Willie
 

bertsmobile1

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If you can not or will not strip the deck to bare metal then PO 15 is a waste of time
Onlt 2 things it chemically bonds to
1 POR 15
2 Rust, but that rust has to be sound & dry.
 

Evil Spirit

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I might not have been clear about how much surface prep I hope to get away with. My surface prep will probably only get me a scale free surface with no loose material - there should be plenty of rust for the POR-15 to bite into.
 

bertsmobile1

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Yes it can bind onto rust but it will not bind onto the remenants of the old paint particularly is it is the really cheap nasty powder coated plastic used by most mower companies now days.
 

Boobala

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Here's a GREAT product I've used for many years, just have to get off the heavy crusted surface rust, then paint this right over it I worked at a marina ( salt-water ) and we used this stuff on everything metal everywhere , I used it on the underside of my deck and on a few places on top before I used the red-oxide primer,

http://www.pettitpaint.com/products/primers/below-the-waterline/rustlok-steel-primer/

scroll down and read the product data sheet.....

100_3456.jpg..100_3460.jpg..DSCN1432.jpg..DSCN1435.jpg..DSCN1685.jpg..DSCN1698.jpg..DSCN1751.jpg..DSCN1762.jpg
 

upupandaway

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...looking for options to coat the underside of the deck....

Don't bother. underneath will sandblast anything off the deck. if anything, i paint underneath with used motor oil. I tried coating underneath with car rustproofing\wax coating. I thought because it acts like the blob and is not solid it might not chip off like paint does. It lasted longer than paint but no- eventually the sandblasting took it off.

Evil Spirit - I used Por 15. their "primer" is good. If u paint with regular paint + primer in a short time, you will see rust developing at places like around the bolts, where to panels overlap. etc. With por, it is very good that this didn't happen- even on my snowblower after 5 years(when i gave it away moving to Tx). Their top coat (Hardnose) is lacking colorwise as in less than 10 years it faded with spots of the color that didn't fade.

In the last few years, when repainting, i am using car paint with clearcoat. I figure if my car can look good after 15 years in the sun, It will work for my stuff. This being everywhere except under mower deck of course...
 

bertsmobile1

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Here's a GREAT product I've used for many years, just have to get off the heavy crusted surface rust, then paint this right over it I worked at a marina ( salt-water ) and we used this stuff on everything metal everywhere , I used it on the underside of my deck and on a few places on top before I used the red-oxide primer,

http://www.pettitpaint.com/products/primers/below-the-waterline/rustlok-steel-primer/

scroll down and read the product data sheet.....

View attachment 42280..View attachment 42281..View attachment 42282..View attachment 42283..View attachment 42284..View attachment 42285..View attachment 42286..View attachment 42287

Nice job, the stuff looks good but the important thing is it bonds to BARE STEEL or RUST, not old paintwork.
Worth noting that you did a bare metal strip.
People who know & understand how these finishing systems work take the time & make the effort to do full bare metal strips.
Joe Average who only knows what they see in paint company video presentations still believe you can just knock off the loose rust then slap on some paint & all will be fine.
It does not work that way.
The stuff looks a bit more user friendly than POR 15 which will go off in the can if you store it for too long.
However the warning about gluing the lid on is interesting as I generally put a layer of cling warp over the POR 15 can having suffered the lid gluing on at one time and all we could do was cut the top off the can.
We painted the badly rusted floor with lots of rust pin holes on one of the hire cars with POR 15 chassis coat back in 82. Did not bother with a top coat because it was going to be covered by the carpets.
In 2010 I sold the car which we had not used for over 5 years and found it had been sitting outside with a window open enough to let the rain in.
The wool carpet had rotted away and the seat supports were also rusted through but the floor pan was just as sound as the day we put the carpet back.

What I would stress is the quality of the finish is dependent upon the quality of the preperation and the OP just wanted to knock off the loose rust then paint over.
This will not work with any paint.
Alkaloid & 2 packs will hang on for a while but eventually will fall off or rust through.

All steel I paint gets POR 15 chassis coat then usually an alkaloid top coat.
For mower decks, the strait POR 15 on the underside and POR 15 with an alkaloid top coat on the outside as I have alkaloids in most common colour matches.
Decks that have flaps, over the discharge chute never rust again and the POR 15 chassis coat is still sound on some decks I did for my commercial customers 3 years ago.
When I said bullets bounce off it I mean bullets bounce off it.
We had to remover some one time and nothing touched it.
The sand blaster eventually wore through but it took near 50 lbs of sand to wear off a small patch.
This was before we realized that if you flip it up into the sunlight, UV eventually ( several months ) will cause the surface to start to powder the same as it does to regular paint, just quicker.
So sun, blasting the sun & more blasting eventually got down to bare metal.
The POR 15 that dripped onto the drive took about 2 years to crumble and wear off.
\
Where you really notice how tough the stuff can be is on things like tensioning arms.
The original finish usually wears through at the pivot in less than one season.
POR 15 coated tensioning arms have gone better than 4 years and the coating is still sound.
 

Evil Spirit

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All good info.

I probably should have been clearer in my first post that I am looking for other options to POR - I have used it for years with great success. As I mentioned, my plan was to POR and topcoat with a good paint, so I was inquiring as to what else is out there.

Not trying to sound lazy on the surface prep, but in reality it's a generic AYP stamped steel deck, which is only worth a couple hundred bucks fully reconditioned with new mechanicals. I can get a deck blasted and powdercoated for about $100 bucks. In reality, it will probably be $50-60 for POR and paint. So with that said, I don't really want to spend more than a couple hours at most prepping a deck for coating - it just isn't really cost/time effective. Hence the "lazy" approach to the surface prep. While a 60" welded steel deck is worth the extra prep and materials, IMO doing more than a good scraping and knock-down with a bristle disc or some 2" discs would probably not be time/cost effective.

And more to consider - this is a deck for a 20 year old "box store" rider. While it's drivetrain may appear sound, any startup may be it's last. On a personal note, I've went from pushing 60 to dragging it, so I'm not going for a 20 year plan.

So, with all this said - any cost effective alternatives to POR? I wonder if anybody has tried the aerosol truck bed liner or rock-guard?
 

BlazNT

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I purchased a brand new deck a while ago and wanted to protect the underside of the deck. I tried 3 different bed liners and not one of them lasted one mow. Nothing works that I have tried. I have not tried Por15 as I did not learn about it until I was done with the project.
 

Boobala

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Willie, that Pettit Rustlok 6980 I used lasted about 1 1/2 yrs, gradually wearing down, BUT I put on 4 HEAVY coats, there is still traces of it in areas but as far as "coating" the underside of decks goes, I think most will agree, unless you stay out of sandy areas and RE-COAT at least every 2 years, it's a lost cause, until they build decks out of vagina's, which is impossible to wear-out, except with age, ..:laughing:: we are doomed to live with what it is !
 
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