Ex Member Posted October 30, 2020 Share Posted October 30, 2020 IME, it does not stick long term to rusty surfaces either. Sand blasted rough is the only thing I've seen make it past 5 years. Now, this is on a vehicle that is used, not a garage queen. Driven all winter in snow, salt and gravel. Normal polyurethanes or enamels are fine and don't peel off with standard surface prep. The POR-15 does not like attaching to things. If you want a durable under vehicle coating, I would suggest regular two part polyurethane or epoxy. Quote Link to comment Share on other sites More sharing options...
jeremy996 Posted October 30, 2020 Share Posted October 30, 2020 I gather it is not good with impact either, which might be your issue. Quote Link to comment Share on other sites More sharing options...
Retroanaconda Posted October 30, 2020 Share Posted October 30, 2020 This may be another option for things being galvanised: https://higalv.co.uk/colourgalv/what-is-colourgalv/ Quote Link to comment Share on other sites More sharing options...
reb78 Posted October 30, 2020 Share Posted October 30, 2020 White90 did a long review of POR15 many years ago on here. I think the overall conclusion was that his chassis was just too clean and shiny when he applied it but the main conclusion was that it wasnt great. For a laugh, i looked up the latest shenanigans of our favourite waxoyler the other day (thankfully very little forum inputs since 2017) but he claims he can no longer get the ingredients for kleenex.... that got worse reviews than POR15. 1 Quote Link to comment Share on other sites More sharing options...
SteveG Posted October 30, 2020 Share Posted October 30, 2020 Hi DD If the bumper is bare steel you could use... https://www.bilthamber.com/paints-and-coatings/electrox Give it two coats as instructed, then after 4 days, scotchbrite it, panel wipe it and then overcoat with whatever paint you find easy to touch up with. Then when you ding it, just touch up. For the top coat CIO or corolless chassis paint are ok, but if you have the hammerite already that will be ok too. cheers steve Quote Link to comment Share on other sites More sharing options...
Dave W Posted October 31, 2020 Share Posted October 31, 2020 Regarding POR-15, I painted my chassis with it 17 years ago. I used the recommended preparation acid stuff etc... My biggest issue with it is that it forms a "skin", sticking to itself really well, that means that if it's damaged or hasn't keyed properly it traps moisture between itself and the chassis with the inevitable results. As I'm currently repairing the bare chassis it's easy to see the parts where it bonded well... and the parts where it didn't. I've touched the paint up a number of times over the years and it's the original bits that looked fine from the outside that are the worst for corrosion. The paint peels off in large sheets like a plastic/powder coating, just a shame that what it was supposed to be protecting is now quite badly corroded. The areas that were "removed" over the years by jet washing etc... and then touched up with zinc primer and chassis black are in far better condition than the POR-15 sections. I'm probably going to get the repaired chassis galvanised this time but if I were to paint it instead I'd stick with the high zinc primer and chassis black over the top simply because those areas that were treated like that 15 years ago, when the POR-15 came off with the jet wash, are fine. 1 Quote Link to comment Share on other sites More sharing options...
reb78 Posted October 31, 2020 Share Posted October 31, 2020 1 hour ago, Dave W said: Regarding POR-15, I painted my chassis with it 17 years ago. I used the recommended preparation acid stuff etc... My biggest issue with it is that it forms a "skin", sticking to itself really well, that means that if it's damaged or hasn't keyed properly it traps moisture between itself and the chassis with the inevitable results. As I'm currently repairing the bare chassis it's easy to see the parts where it bonded well... and the parts where it didn't. I've touched the paint up a number of times over the years and it's the original bits that looked fine from the outside that are the worst for corrosion. The paint peels off in large sheets like a plastic/powder coating, just a shame that what it was supposed to be protecting is now quite badly corroded. The areas that were "removed" over the years by jet washing etc... and then touched up with zinc primer and chassis black are in far better condition than the POR-15 sections. I'm probably going to get the repaired chassis galvanised this time but if I were to paint it instead I'd stick with the high zinc primer and chassis black over the top simply because those areas that were treated like that 15 years ago, when the POR-15 came off with the jet wash, are fine. Theres an irony here ... you have done all of this to protect your chassis and mine has had a couple of sprays over with waxoyl and at 31 years is nearing the need for replacement (it has had a few patches). This isn't a criticism at all. We all feel we are doing the right thing and weigh up time and money in those decisions and it just makes me wonder if we did nothing compared to the effort of painting like you or the intermediate like me.... i still don't think anyone has hit on a solution (other than replacement with a galv chassis) that really works. Quote Link to comment Share on other sites More sharing options...
HoSS Posted November 1, 2020 Share Posted November 1, 2020 On 10/31/2020 at 2:21 AM, Dave W said: Regarding POR-15, I painted my chassis with it 17 years ago. I used the recommended preparation acid stuff etc... My biggest issue with it is that it forms a "skin", sticking to itself really well, that means that if it's damaged or hasn't keyed properly it traps moisture between itself and the chassis with the inevitable results. I cant comment on POR15, but it sounds like the prep was not done correctly, perhaps oil or other contaminants. Even standard paint can stick if done well. My 45 year old Volvo chassis just had standard paint, albeit with a think layer of military bitumen over 80%, and when stripped back the metal is like it left the factory. Even some of the paint does not want to come off easily in blasting. Galv is great, but so is almost any paint if its applied correctly. And theres the tricky part, we do our best, but without industrial blasting, perfect degreasing etc there can be issues. Quote Link to comment Share on other sites More sharing options...
reb78 Posted November 1, 2020 Share Posted November 1, 2020 I guess prep and application are actually really really hard... particularly while the body is on. Its horrible work, especially laying on your back na drive and even with a ramp, some bits of the chassis are near impossible to get to with a brush, wire brush or blaster etc etc so prep is also impossible. Then you paint what you can perfectly and end up with a seam between well prepped and poorly prepped areas that water can get into/under and rust can work forwards from. This is why I went for waxoyl - I thought it stood a chance of working even on the poorly prepped areas. My prep was a really really good wash with an industrial steam pressure washer (but this was far from perfect as I had to do this on the floor even though I am lucky enough to have a ramp (its inside so cant pressure wash in there). Then there is the inside of chassis.... you cant clean or paint properly in there... Quote Link to comment Share on other sites More sharing options...
Dave W Posted November 1, 2020 Share Posted November 1, 2020 In my case I was working on a bare chassis and spent many hours prepping it, following the instructions to the letter. It may be that in lab conditions POR-15 works fine and it may also be that on a chassis which didn't spend half it's life immersed in mud, banging over tree roots and rocks, it would work fine. The reality though is that it's sold for DIY use and it's sold as a way of protecting a chassis and, in that respect it fails on both counts IME. It's annoying because I was sold on the idea that this coating would protect the outside of the chassis for many years, saving me my current rebuild. All it actually did was prevent me adequately "topping up" the protection over the years by hiding the problems that were building up behind it. As I said, the bits where it obviously failed are fine because they were topped up with zinc primer and chassis black, it's the bits that appeared OK where the problems have been. With the above experience in mind I think a more traditional high zinc primer is easier and more reliable to apply in the real world and any issues can be seen and easily resolved over time. The inside of the chassis, especially a used one is the bigger issue. On mine, assuming I get it galvanised after the repairs, I've cleaned out as much of the sand and mud as I can and can only hope that the acid treatment does it's job before the galvanising. Before starting re-building I'll fill the chassis with Dinitrol and paint the outside of they chassis. To be fair, if it lasts another 20 years it'll probably outlast me and I doubt I'll be able to rebuild it again if it doesn't, even if we are still allowed to drive such vehicles in the UK. Quote Link to comment Share on other sites More sharing options...
landroversforever Posted November 1, 2020 Share Posted November 1, 2020 3 minutes ago, Dave W said: In my case I was working on a bare chassis and spent many hours prepping it, following the instructions to the letter. It may be that in lab conditions POR-15 works fine and it may also be that on a chassis which didn't spend half it's life immersed in mud, banging over tree roots and rocks, it would work fine. The reality though is that it's sold for DIY use and it's sold as a way of protecting a chassis and, in that respect it fails on both counts IME. It's annoying because I was sold on the idea that this coating would protect the outside of the chassis for many years, saving me my current rebuild. All it actually did was prevent me adequately "topping up" the protection over the years by hiding the problems that were building up behind it. As I said, the bits where it obviously failed are fine because they were topped up with zinc primer and chassis black, it's the bits that appeared OK where the problems have been. With the above experience in mind I think a more traditional high zinc primer is easier and more reliable to apply in the real world and any issues can be seen and easily resolved over time. The inside of the chassis, especially a used one is the bigger issue. On mine, assuming I get it galvanised after the repairs, I've cleaned out as much of the sand and mud as I can and can only hope that the acid treatment does it's job before the galvanising. Before starting re-building I'll fill the chassis with Dinitrol and paint the outside of they chassis. To be fair, if it lasts another 20 years it'll probably outlast me and I doubt I'll be able to rebuild it again if it doesn't, even if we are still allowed to drive such vehicles in the UK. As Galv places are wary of 'old' chassis, it's probably worth looking at having it chemically stripped elsewhere first. Quote Link to comment Share on other sites More sharing options...
Dave W Posted November 1, 2020 Share Posted November 1, 2020 3 hours ago, landroversforever said: As Galv places are wary of 'old' chassis, it's probably worth looking at having it chemically stripped elsewhere first. The place I spoke to a couple of months ago said they were happy to take it "as is" and said the only problems they'd had was with some water based paints which their cleaning bath doesn't strip. They use some form of acid/stripping bath to clean the chassis prior to the galvanising bath and seemed to think it would be fine. I was surprised they'd take a used chassis TBH as I'd spoken to a few places that wouldn't touch them due to the issues of contamination. As soon as I said what it was I wanted galvanising they seemed to know what to expect and said that their cleaning/stripping process would take care of it. They seem to mainly do structural stuff so referred to Land Rover chassis as being "fragile" so they'd have to handle it separately. 1 Quote Link to comment Share on other sites More sharing options...
Ed Poore Posted November 1, 2020 Share Posted November 1, 2020 I'm lucky enough to have a trailer manufacturer down the road where I can drop anything off and pretty much guarantee to have it back within a week galvanised. Most of the places are happy to accept "rust" coatings and mill-scale on the steelwork but paint was a definite no-no. Some will accept it but you might be liable for a penalty for them having to replace their pre-dip baths. Quote Link to comment Share on other sites More sharing options...
Blanco Posted November 3, 2020 Share Posted November 3, 2020 On 10/29/2020 at 9:55 PM, simonr said: My slightly unusual suggestion is Floor Paint. I have just painted my floor in one part PU floor paint and its qualities had me thinking it would make good chassis paint, or anything paint come to that. I notice that Retropower have mentioned they use colour matched Raptor on the underside of all their builds, but that is after the second blasting and the hot zinc spraying. How involved is hot zinc? I take it that isn't a DIY propostion? Quote Link to comment Share on other sites More sharing options...
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