Nickffc Posted November 10, 2017 Report Share Posted November 10, 2017 Just about to have the chassis blasted then etch primed... Going to use the POR 15 stuff to seal and paint. the question is, how much do i need to paint the whole thing? Was also thinging about spraying the inside of the frame with the same using air undersel gun with long flexy tubing for all the hard to get too places. Nick Quote Link to post Share on other sites
Don H. Posted November 10, 2017 Report Share Posted November 10, 2017 I don't think I'd use POR-15 over an etch primer. The stuff likes bare metal, and not perfect metal at that. If over another coating I'm sure there are better choices. POR-15 directly on the blasted metal would be fine. POR-15 is a serious pain to use. It has difficult flow, doesn't like to spray, tends to run, and will dry to an absolutely not-removable coating on anything (including skin). Don't get me wrong -- I love the stuff, and will open a small can this weekend for a few projects, but its strengths do not include application ease. I buy the smallest cans they sell in multipacks to minimize waste. I seal the top with a sheet of polythene film to prevent it from being welded shut and store the cans upside down to minimize the chance of moisture getting in (which is what initiates curing). A little goes a long way. I've not painted an entire chassis, but I'd expect a quart to be too much. Quote Link to post Share on other sites
stallie Posted November 11, 2017 Report Share Posted November 11, 2017 Yes, less that you think. The other thing I’d suggest is por 15 the first coat a gray, then the top coat another colour. Otherwise it’s a pain to see where you’ve done and where you haven’t. The single coat patches you miss look terrible. Quote Link to post Share on other sites
Don H. Posted November 11, 2017 Report Share Posted November 11, 2017 ^ That's a good idea. Black on black definitely will lead to missed spots. Ask me how I know... Quote Link to post Share on other sites
RogerH Posted November 11, 2017 Report Share Posted November 11, 2017 ..Can you over paint POR-15 Hi Nick, seriously think about using the POR-15. It dries to a very hard finish. If it gets bashed then it may chip off rather than scratch. This could lead to hidden corrosion later on. Have you considered using BondaRustPrimer straight onto the metal. https://www.ebay.co.uk/itm/BONDA-RUST-PRIMER-2-5LTR-FREE-DELIVERY/122780389432?hash=item1c96481038:g:UWEAAOSwjk9ZUmVn This sticks extremely well, is easily applied, with all appliances, and there is no need for etch primer (etch prier on steel !!!! ) Will the chassis internals very well. It will take a primer and top coat easily - or just a simple chassis paint. And then a waxoyl type coating to finish. Roger Quote Link to post Share on other sites
Don H. Posted November 11, 2017 Report Share Posted November 11, 2017 Yes, one can paint over POR-15. In fact, one should paint over it, unless the item will never see UV light, as POR-15 isn't UV stable. Regarding chipping. Fat chance. From my experience there is NO WAY that finish is coming off anything it's put on. It ain't getting chipped. Quote Link to post Share on other sites
pinky Posted November 11, 2017 Report Share Posted November 11, 2017 hi nick, the way to go is epoxy paint, it is unbelievable good, pink Quote Link to post Share on other sites
RogerH Posted November 11, 2017 Report Share Posted November 11, 2017 Hi Don, thanks for the info on the over painting and Uv protection. I would have thought very few things would survive a good pounding on the bottom of the chassis. Roger Quote Link to post Share on other sites
88V8 Posted November 11, 2017 Report Share Posted November 11, 2017 This stuff is bomb-proof. http://www.rust.co.uk/em-121-epoxy-rust-proofing-chassis-paint/c28117/ Never tried spraying it though. Ivor Quote Link to post Share on other sites
Don H. Posted November 11, 2017 Report Share Posted November 11, 2017 One could probably sandblast off POR-15 -- but not easily -- and I guess if it were exposed to enough of something similar on the roads it would be abraded away -- but if that's the case, the chassis is going to be down to bright metal with any coating! POR-15 is seriously tough. Quote Link to post Share on other sites
Nickffc Posted November 11, 2017 Author Report Share Posted November 11, 2017 well that set the cat amoungst the pigeons... i thought i was set on using POR15 but now not so sure...!! i get the whole dont bother primeing which makes sence i guess, so it may be that i get the chassis blasted then get it home and hopfully not raining. i do have the luxury of having a heated garage so mosture ingress before painting is not really a problem. the tub and chassis have been in the gargre now for 18 months in various states of bare metal with any surface rust forming. really helpfull replys.. thanks, maybe blinkered towards the POR15 system. chassi is off to blaster next Thursday so i'd better make a decision soon..! cheers Nick Quote Link to post Share on other sites
Nickffc Posted November 11, 2017 Author Report Share Posted November 11, 2017 (edited) did try to creat a poll but gave up... :) Edited November 11, 2017 by Nickffc Quote Link to post Share on other sites
Guest ntc Posted November 11, 2017 Report Share Posted November 11, 2017 (edited) Bondarust on dry frame,then chat with a good paint supplier ,I use humberside paint Scunthorpe they supply cemex/tarmac cement wagons think about it? you can brush or spay but not without face mask. Edited November 11, 2017 by ntc Quote Link to post Share on other sites
Don H. Posted November 11, 2017 Report Share Posted November 11, 2017 There have been a number of people who have tested POR-15 under varying degrees of experimental rigor, and it always comes out equal or better than anything. I've used it for years, and I will swear there's nothing better in preventing rust from starting or returning. No paint as bothersome to use as POR-15 could survive in the market if it didn't give incredible results in protecting against rust. It does that. It's pretty common over here for people to powder-coat chassis, and it might come up in your deliberations, Nick. That's a poor choice, IMO (and I've worked for decades in coating research / polymer technology, BTW). Polyester powder coats look smooth and shiny, which I guess appeals to some before the chassis is under the car. But powder coats are susceptible to cracks in the coating and corrosion running under the coating worse than it would have been with nothing. Powder coats are difficult to repair. Definitely not the solution for a chassis. As an example of powder coating's vulnerability, note the end plate on the receiver hitch on my Toyota pickup: Quote Link to post Share on other sites
ed_h Posted November 11, 2017 Report Share Posted November 11, 2017 I`ve used POR15 and similar competitors quite a bit, including on my TR6 frame. I think it is a good choice for an application that would be difficult to spray. As for durability, I'd put in the same class as a good two part epoxy primer. On my TR6 frame, I used less than a quart each of gray and black. Then topcoated with conventional black for some UV protection. Ed Quote Link to post Share on other sites
stallie Posted November 11, 2017 Report Share Posted November 11, 2017 POR15 actually chemically binds the the metal. If you paint the second coating too soon, you will see small bubbles form, from the first layer as it is still reacting to bind the the metal. Quote Link to post Share on other sites
Nickffc Posted November 12, 2017 Author Report Share Posted November 12, 2017 Powder coat was never an option.... it looks like it might of been PC'ed before as areas come off in sheets. Been reading more about PO15 and expoy paints and i think i will stick with the POR. not going to have the chassis primed, but use the rust preventive first coat grey and then the POR chassis coat black which is not UV sensitive. brush application for the outside and apparently there is a POR thinner that can be used for spray appliaction so i can get the internals done too.... but we will see. there are lots of products for the internal chassis sections so more reading to be done. cheers Nick Quote Link to post Share on other sites
Don H. Posted November 12, 2017 Report Share Posted November 12, 2017 Nick, while POR-15 (the rust protecting stuff) is a special product, Chassis Coat Black is nothing special. No dings against it, but nothing special to commend it either. There are likely many alternatives you could use as a topcoat. POR-15 has instructions for overcoating that are probably worth following. It's not a job one wants to do twice. Quote Link to post Share on other sites
Nickffc Posted December 10, 2017 Author Report Share Posted December 10, 2017 (edited) Chaps Many many thanks for all your input... chassis blasted by a really good bloke local to me who after talking to him and seenig the result i think i will get him to do the boady too... he's really knows his stuff. i will probabaly paint strip all the big flat panles and get him to do the hard to get to places. he had a couple of other classics on site (E-type and an old BMW) so confidence is high... i did use the POR15 in the end and i'm really pleased with the results i've updated the blog if your interested.... http://nickstr6.weebly.com/ all the best nick Edited December 10, 2017 by Nickffc Quote Link to post Share on other sites
Don H. Posted December 10, 2017 Report Share Posted December 10, 2017 Looks good, Nick! Quote Link to post Share on other sites
pfenlon Posted December 10, 2017 Report Share Posted December 10, 2017 It does look good, but why not powder coat it ? Only costs £120. Quote Link to post Share on other sites
Guest ntc Posted December 10, 2017 Report Share Posted December 10, 2017 Because it don't last. Quote Link to post Share on other sites
SeanF Posted December 10, 2017 Report Share Posted December 10, 2017 Looking good Nick. Be careful having outer panels blasted due to the risk of warpage. Don't let them anywhere near the bonnet or boot lid and only do the rounded or swaged areas of the other panels. Quote Link to post Share on other sites
Nickffc Posted December 10, 2017 Author Report Share Posted December 10, 2017 (edited) yeah i know about the outer panles... hes keepng well away from them, he will doing the hard to get to bits... powder coat is personle preferance and after researching found that powder coat is ruined once it chips.... and unfortuntly it will chip and rot the inside of the frame out while the remaing coating stays intact... then its tooo late. TVR powder coat from the factory.... and is one of the main reasons you can pick up cheap TVR's now...! i am powder coating at home all the smaller suspension parts and appreciate that these too will chip but easy to get at and fix... unlike the chassis to each their own.... looks great BTW Nick Edited December 10, 2017 by Nickffc Quote Link to post Share on other sites
pfenlon Posted December 10, 2017 Report Share Posted December 10, 2017 Just 1 of many articles proving Powder coating is a better medium for the chassis, but some people are still covering them with underseal etc ..................... http://www.hotrod.com/articles/ctrp-0908-powder-coating-vs-paint-jobs/ Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.