|09-23-2005 12:33 PM|
Use some 80-180 to clean it up with. Do not sand off the galvanized if you can keep from it.It's just a thin layer over plain steel and if you get aggressive with it,it's gone.
Another reason to use epoxy IMO as even if you sand the galv. off,it's great protection against rust. Just be SURE it's CLEANED well with a wax & grease remover THROUGHLY before any epoxy or any type primer for that matter. Use clean white rag's till there is no residue on the rag after wiping.
|09-23-2005 07:57 AM|
|09-22-2005 12:49 PM|
I work in a sheet metal shop and it's been an old tale for a long time about vinigar use before paint. Galvanized need's a scratch or something to etch into it for the paint to adhere to as it's slick. Like painting chrome or polished metal. The vinigar just is not strong enough to actually etch for paint. It's a fair pre cleaner but all my experience trying it has been flaking paint after a while in the weather.We do chimney cap's,some of which have been on for 10 years,that were etch primed then painted that are still in good shape today.
I'd use an etch IF you already have it,BUT,I'd use 2 coat's of epoxy after stripping/sanding instead as it will provide better long term protection and a better base to work over.I just prefer epoxy on automotive app's as it's a long term,great base compaired to etch.
|09-22-2005 07:13 AM|
So, maybe I should just strip the paint, clean things very good and hit it with self etch primer. You say the vinegar just cuts off the oils and grease but not for long term. What do you mean by that?
|09-21-2005 07:57 AM|
I use an etch primer on a true galvanized metal but the e-coat panels are just scuffed and epoxied then 2k blocking primer.
The problem with using acid such as muriatic is it strips the galvanize completely off and you end up with a piece of bare steel which will flash rust almost instantly defeating the whole purpose of using galvanized in the first place.The vinegar trick dosen't work well as it is not strong enough to actually etch the metal,it just cut's off the oil's and grease so the paint will adhere but not for long term.
|09-21-2005 07:17 AM|
How about a Galvanized Cowl?
The upper cowl on a 68 Mustang I’m going to repaint is galvanized and the old paint is pealing. Should I strip the paint, scuff the metal and just shoot it with a self-etching primer? I have some Dupont Variprime 615S and all the tech manual says is to apply it to “Properly prepared/cleaned steel, aluminum and galvanized”.
|08-13-2005 04:08 PM|
Remove galvanise coat
a poisonous gas off when the chemical reaction take place thereafter coat with primer. I have done gavanized sheet plates it go back to the black plate stage
before it was galvanized
|08-29-2002 03:25 PM|
|philPKP||Metalman ya did"nt have ya fan pointin EAST did ya? <img src="graemlins/sweat.gif" border="0" alt="[sweat]" />|
|08-27-2002 02:28 AM|
Hi, I restore cars for a living and am very impressed with a product called rust destroyer which is basically a special primer that killed rust and corrosion and it can be applied on various metals including galvanized metal. I've used it on galvenized a number of times with great results, it far exceeds its guarantees.
By the way I hope you are welding that stuff in a well ventilated area, the fumes from galvanized metal are known to have killed people almost instantly. I always have a fan nearby when I weld any toxic metal, as well as the big shop blower vent on with a door open at the opposite end. Goodluck ~~Metalman~~
|07-24-2002 10:03 AM|
|bullheimer||painter boss here says zinc chromate primer then you can paint it with anything. as per 2oldster/4jaw|
|07-21-2002 09:48 AM|
|johnny 1986||A real easy and cheap way to etch galvinized metal is white vinegar from the grocery store. It will not work on aluminum and is useless on mild steel. For aluminum use alodine. For mild steel use phophoric acid. Dupont and PPG both sell these chemicals under a "trade name" Read the labels to make sure you are using the appropriate chemical for the application. Back to the original question, scrub the galvinized metal lightly with white vinegar and scotch-brite and rinse with tap water and dry with clean cloth. Do not let air dry. Prime with a catalized type primer only. Lacquer based primer usually will work but it will definitly fail sooner than a catalized type. Why take the chance. Lacquer type primer went out with the high-button shoes. Good luck.|
|07-18-2002 07:36 PM|
[quote]Originally posted by Madd Syntst:
<strong>I know the trill of welding galvanized, but what about painting it? I know there is something you need to prep it with or etch it before primer. I am making a tube grill from electrical EMT </strong><hr></blockquote>
you can use a self etching primer,spies-hecker brand has a real good one,dont know if you have a spies dealer where you are,if not they are located in warren,michigan and will ship to you on cod.
|07-17-2002 07:18 AM|
OK guys, this is what I did. I sanded them down real good and then welded them together. Cleaned the metal again. Washed them down with muratic acid solution (Cheap Buzz there) rinsed real good. Washed in vinegar(Apple cider, not red wine) and rinsed. Scotch brite and Comet, rinse. Self etching primer, and black paint, clear coat. The grill goes in tonight. I will be posting a new photo as my avatar over the weekend for all to see. The real proof will be how does it weather thru the next few months.
Dirtbag, I'm worried about you and your nutritional habits
[ July 17, 2002: Message edited by: Madd Syntst ]</p>
|07-17-2002 12:43 AM|
We always used "Galvaprep" at the body shop when painting anything that had zinc all over it. etches nicely, but don't try to drink it.
|07-16-2002 10:29 PM|
Madd, if you wish to paint galvanized metal, before using a regular primer you must first use a self etching primer. Eg: Martin seniors "Trio Prime" is an excellent product. I have had excellent results with this and have never had a problem with flaking paint etc. Caution is addvised with this product in that you want to have good ventalation and personal safty equipment. read the product data sheet.
This works well for full coverage and for spot repairs. I hope that you find this info helpful...Martin
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