Making paint stick

[darthdicky]

Painting my bumper at the moment and starting to think that either Hammerite isn’t the right thing to use or I need to improve my technique! What’s the best way to get it to really stick well? What’s the best way to prepare the surface? Do I need to put primer on first?

Not looking for spectacular finish, just something that doesn’t scratch off with the slightest touch. Also want to do the axles at some point so want to get this done properly.

[FridgeFreezer]

Rough it up a bit, wipe it down with brake cleaner, don't use hammerite it's pants.

Buzzweld Chassis-In-One or Corroless from ArcRite.

[reb78]

You dont have a galvanised bumper do you?

[landroversforever]

Vote for POR15 here. Waaaaaay better than hammerite. Has it been painted before or Galv?

[miketomcat]

Just about anything is better than hammerite these days. I used jotamast 90 epoxy primer and a truck chassis paint on my chassis and have used por15 both seem ok. Smaller stuff I rattle can some etch and top coat. Either way a good sand up first definitely helps.

Mike

[monkie]

3 steps to a good finish:

1.Proper surface preparation to remove dirt/grease/loose material and provide a good key. If galvanised then you need to acid wash. 

2.Quality etch primer for your bumper. A few thin layers better than 1 thick. I use U-Pol and get good results. 

3. Any of the paints mentioned above. For axles I have used corroless and the finish lasts for years. 

[missingsid]

I used Hammerite Smooth for my axles, when it went on it left brush marks showing metal as it did not stick but a couple of coats and it was fine. Still on some years later.

Next time I will try POR15 as it has great reviews and if it covers in a single coat then that is a win.

[HoSS]

Sandblast & degrease is the best. Etch primer (or special for galva), or an expoxy paint like EM121.
I've just done a chassis in that and it sticks like the proverbial poop and is super tough https://www.rust.co.uk/product/cat/em-121-epoxy-rust-proofing-chassis-paint-7

I've not used POR, but i imagine the EM-121 is similar or even the same.

 

[Retroanaconda]

12 hours ago, FridgeFreezer said:

Buzzweld Chassis-In-One or Corroless from ArcRite.

The Buzzweld CIO on my chassis has stuck well enough but has sadly been destroyed by road salt within a few years.

The chassis is due to be blasted and re-galvanised in the near future and so I will try something else this time. 

[Nonimouse]

Buzweld is good, but it's delivery is utterly useless

[Jon W]

Tractol Paint seems quite good that I have used. Sand it hard, then maybe try spraying lots of light coats to get it to stick better. Primer 1st, then cheap topcoat. Yes hammerite is carp. 

[FridgeFreezer]

Just to note that POR15 is not UV stable, OK on axles/chassis but may fade on bumpers.

[simonr]

My slightly unusual suggestion is Floor Paint.

I used it on a roll cage - and it just would not scrape off in the way anything but powder coating does.

The paint was nothing special, just bought locally from Brewers.  Painted directly on to the metal.

I guess if it survives years of forklift traffic - a bumper, axle or cage is trivial.  I've been using it ever since!

Another tip.  There's a 'certain company' who paints Chassis with something they claim mud will not stick to.  I wondered what it might be - and my conclusion was Anti Vandal paint.  Nothing sticks to it, including other paint but it seemed to work reasonably well.  The only down side of it is the surface needs to be very very clean and with a good key otherwise it just flakes off. 

[HoSS]

Not silly, i have epoxy floor paint in the garage (actually its road white line paint dyed grey. No it didn't fall off the back of a lorry) and that sticks to anything.

[Blanco]

13 hours ago, simonr said:

and it just would not scrape off in the way anything but powder coating does.

Interesting comment,... my only experience of powder coating was a Bearmach winch bumper I had on the D2, it was complete rubbish and most ofit flaked off, after about 4 years I took the bumper off, modified it slightly, shot blasted it and just painted it in ordinary paint, I was totally unimpressed with powder coating.

[simonr]

20 minutes ago, Blanco said:

my only experience of powder coating was a Bearmach winch bumper..........

Maybe I should say, Decent Powder Coating!  Hot zinc spray & powder coat.

[landroversforever]

52 minutes ago, Blanco said:

Interesting comment,... my only experience of powder coating was a Bearmach winch bumper I had on the D2, it was complete rubbish and most ofit flaked off, after about 4 years I took the bumper off, modified it slightly, shot blasted it and just painted it in ordinary paint, I was totally unimpressed with powder coating.

There's a lot of stuff with really poorly done coatings these days, sadly I think just done down to a price. My First Four bumper has had a beating and still looks great. 

[FridgeFreezer]

There's good & bad powder coating, a lot of the cheap stuff is more like plastic-dipped than properly powder coated.

[Snagger]

2 hours ago, Blanco said:

Interesting comment,... my only experience of powder coating was a Bearmach winch bumper I had on the D2, it was complete rubbish and most ofit flaked off, after about 4 years I took the bumper off, modified it slightly, shot blasted it and just painted it in ordinary paint, I was totally unimpressed with powder coating.

Mantec products rusted in weeks through their powder coating.  The problem was not the powder coat itself but the complete lack of metal preparation - they didn’t descale, de-rust or even clean the metal, and they never demurred the edges of stamped parts like window grilles, so the covering was compromised from the start.

[mickeyw]

19 hours ago, simonr said:

Another tip.  There's a 'certain company' who paints Chassis with something they claim mud will not stick to.  I wondered what it might be - and my conclusion was Anti Vandal paint.  Nothing sticks to it, including other paint but it seemed to work reasonably well.  The only down side of it is the surface needs to be very very clean and with a good key otherwise it just flakes off. 

Ahhh, that company. I'd forgotten about them and their grey coating.
Both people I know of that went to them found the product didn't stick very well.

 

On the Buzzweld CIO front, I have used that on my 110 for quote a while. It covers well, dries fast and sticks pretty well (especially to one's hands), but doesn't seem to stay good for that long. After a few off-roading sessions and subsequent jet washes there seems to be rust coming through. 

For painting agri equipment I've been brushing on a zinc rich primer from Arc Rite, followed by one of their satin finish industrial paints. This combo seems pretty resistant to knocks and bumps.

[Ex Member]

On 10/28/2020 at 5:27 PM, landroversforever said:

Vote for POR15 here. Waaaaaay better than hammerite. Has it been painted before or Galv?

Getting POR15 to stick to something (long term) is much harder than most coatings.

[landroversforever]

1 hour ago, Red90 said:

Getting POR15 to stick to something (long term) is much harder than most coatings.

It’s not any more difficult. 

[Ex Member]

11 minutes ago, landroversforever said:

It’s not any more difficult. 

I disagree.  I've used it for 20 years and getting it to stay on for long term is very hard.  Sand blasted surfaces are the only thing I've seen it stay attached to.  3 to 5 years and it starts to peal otherwise.  Normal paint preparation does not work.  It comes loose eventually.

[landroversforever]

I've got several friends that have used it long term without any issues. The only thing it doesn't like is shiny surfaces.

[jeremy996]

POR-15 seems to like a lightly rusted surface to stick.

The Morgan community were using it about 10-15 years ago when it was supposed to be the greatest thing since........

Subsequently, owners have complained about it not being UV stable, coming off in sheets, ruining other coatings, being very toxic and only sticking well to hands and rubber gloves.