I'm looking to repaint the front fork on my army bike, as it has worrying rust. I've gotten a hold of the original one-size-fits-all green army paint, but I thought that maybe I'd want to do a little extra. At a local hardware store, I found a can of "cold galvanizing zinc spray" ("zinkspray, kallgalvanisering," in any case) for use as an undercoat or primer on things like boat trailers.
Would this hurt, help, or do nothing?
(BTW, as long as it still ends up green, I don't care how ugly the paint job turns out.)
I'm looking to repaint the front fork on my army bike, as it has worrying rust. I've gotten a hold of the original one-size-fits-all green army paint, but I thought that maybe I'd want to do a little extra. At a local hardware store, I found a can of "cold galvanizing zinc spray" ("zinkspray, kallgalvanisering," in any case) for use as an undercoat or primer on things like boat trailers.
Would this hurt, help, or do nothing?
(BTW, as long as it still ends up green, I don't care how ugly the paint job turns out.)
go to the hardware store and get one of the paints that stabilizes the oxides. i forget name brands, but you can wire brush, paint, leave 6 weeks [for the chemistry to work], and repaint to your desire. don't bother with that zinc [censored].
If you do go the "cold galv." route, you can help insure the paint adhesion by wiping the galv. w/ a mild acid such as vinegar. Rinse the acid off prior to painting. Cold Galv. works surprisingly well for such a "quick & dirty" option. Just don't paint over shinny zinc.
"Adam Rush" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
I'm looking to repaint the front fork on my army bike, as it has worrying rust. I've gotten a hold of the original one-size-fits-all green army paint, but I thought that maybe I'd want to do a little extra. At a local hardware store, I found a can of "cold galvanizing zinc spray" ("zinkspray, kallgalvanisering," in any case) for use as an undercoat or primer on things like boat trailers.
Would this hurt, help, or do nothing?
(BTW, as long as it still ends up green, I don't care how ugly the paint job turns out.)
Use something like Naval Jelly to strip all the oxide. It leaves an iron phosphate coating that is stable, bites paint, and helps to prevent future corrosion. If you leave rust on the surface then noting layered on top helps or stays put.
As an undercoat before applying your army green paint, I doubt that you'll have problems unless the army green paint is lacquer-based.
What exactly is lacquer? Is that synonymous with acrylic, in practice?
Acrylic fractions may be found in both lacquers and enamels. Most solvent-based paints sold today are enamels.
Lacquer is a type of solvent-based paint which differs in several ways from enamels. It's not used much anymore, but there's a possibility that if it's old stuff, the army-green paint you have might be lacquer. If it is, and if the cold galvanizing compound uses a vehicle that's more like enamel, the whole thing could end up looking like wrinkle-finish paint. If that happens, let it dry a bit, scrape and wipe off the mess with a solvent rag, and then paint again with just the army green paint. -- Typoes are a feature, not a bug. Some gardening required to reply via email. Words processed in a facility that contains nuts.
One other note: In my experience, cold galvanizing coatings will not stop or [censored] corrosion that's already present.
Even if sandpapered off? I'm not to good with Rust Dynamics 101.
Sandpaper levels off the corrosion to the surface of the surrounding metal. If there's any penetration of the corrosion below the surface, sandpaper won't get it out unless used more vigorously than you are likely to want to attempt.
-- Typoes are a feature, not a bug. Some gardening required to reply via email. Words processed in a facility that contains nuts.
"Werehatrack" wrote: (clip)there's a possibility that if it's old stuff, the army-green paint you have might be lacquer. If it is, and if the cold galvanizing compound uses a vehicle that's more like enamel, the whole thing could end up looking like wrinkle-finish paint. (clip) ^^^^^^^^^^^^^^^^^^^ Dear "Rack--I think you may have your facts reversed. It is lacquer that will wrinkle existing enamel. Putting enamel over lacquer should be no problem.
If the surface is rusty AND pitted, then sanding will likely not get all the rust. I suggest using a primer like Rustoleum, which is formulated to penetrate rust and arrest it. There is extra oil in this type of primer which is supposed to penetrate the rust, surround it, and then dry, leaving a stable surface for finishing. There are also spray finishes which are formulated to go directly over rust. They work for me, but I have no long-term results to prove they are REALLY good.
Cold galvanizing compounds do work, but they require meticulous preparation of the base metal. Used correctly they are very effective, but that usually means sandblasting followed by immediate cold galvanizing. This ensures good electrical contact between the zinc in the paint and the base metal. Any trace of rust or other insulating debris on the surface will defeat the project. In a humid atmosphere the interval between cleaning and galvanizing should probably be measured in hours.
The "cover all" rust cure paints work to some extent, with much less careful preparation, usually no more than just removing loose rust with a wire brush. Typically they're a water-based emulsion paint with something like phosphoric acid added. The acid converts the rust to something which does not take part in the rust chemical cycle and ties up any free water. The paint seals out any new water.
My experience was in the late 1970's, I doubt the chemistry has changed much, surely the brand names have. The cold galvanizing compound was from ZRC, I think this might be their website: http://www.zincrich.com/p_zrc.asp
Sorry, but I can't remember the name of the "cover all" antirust paint. [sound of creaky brain cells rubbing together]
"Werehatrack" wrote: (clip)there's a possibility that if it's old stuff, the army-green paint you have might be lacquer. If it is, and if the cold galvanizing compound uses a vehicle that's more like enamel, the whole thing could end up looking like wrinkle-finish paint. (clip) ^^^^^^^^^^^^^^^^^^^ Dear "Rack--I think you may have your facts reversed. It is lacquer that will wrinkle existing enamel. Putting enamel over lacquer should be no problem.
I stand corrected. It's been so long since I encountered it that I had forgotten which order caused the problem, but you're correct.
Quoted message said:
If the surface is rusty AND pitted, then sanding will likely not get all the rust. I suggest using a primer like Rustoleum, which is formulated to penetrate rust and arrest it. There is extra oil in this type of primer which is supposed to penetrate the rust, surround it, and then dry, leaving a stable surface for finishing. There are also spray finishes which are formulated to go directly over rust. They work for me, but I have no long-term results to prove they are REALLY good.
My own experience with the older Rustoleum products was less than stunning, but the later formulations have been better. For real durability, however, nothing can compare with the results obtained by painting a surface that has no corrosion at all.
-- Typoes are a feature, not a bug. Some gardening required to reply via email. Words processed in a facility that contains nuts.
"Adam Rush" <[email hidden]> wrote in message news:[email hidden]...
Quoted message said:
I'm looking to repaint the front fork on my army bike, as it has worrying rust. I've gotten a hold of the original one-size-fits-all green army paint, but I thought that maybe I'd want to do a little extra. At a local hardware store, I found a can of "cold galvanizing zinc spray" ("zinkspray, kallgalvanisering," in any case) for use as an undercoat or primer on things like boat trailers.
Would this hurt, help, or do nothing?
Somewhere between help a little, and nothing. Zinc corrodes faster than iron, the oxides don't hydrate as much. Zinc oxides are easily removed compared to iron oxides, thus galvinizing is very much favored for iron/steel surfaces that won't get a decent paint job.
But if you're going to paint it afterwards, I'd skip the galvinizing in favor of more sanding and priming.
clean, rust-free surfaces clean, rust-free surfaces and in out of the way places unlikely to be trod on by large animals or thrown monkey wrenchs and concrete blocks-the stuff chips then rusts some time later as the ions waft off to pluto for the latter-the rusto system is good but car paint is best looking linseed thinned, allowed to dry(several months in arizona) then coated with rusto is farmall approved but question is REALLY who looks? you forecast crowds coming by to ogle your fork?
oh yeah-its the swedish contingen no, cold galvanizing isn't it. CG is to coat clean surfaces or hopeless surfaces using the linseed based CG i experimented with linseed over a clean wire brushed rusted surface-allowing linseed to dry without intervening water-then coating with the rusto system and several times a metallic latex in between to eliminate water penetration. what this does is trap the rust without additional water or oxygen-the rust hardens and basically goes no further. but this is on a seeable surface and that's not the situation with da forks with da forks you need to eliminate interior rust to eliminate the chances of your diving under the oncoming bus when the foprk collapses like this is an OLD OLD OLD piece your getting your weight on: check around for glenn curtiss in linbe four motocycles-priceless! boil it your self in caustic or take it to the shop. 'car restoration rust removal' is google searchable and there are home shop products for serious rust removal-treat the bike like a '49 maserati touring an assumption you can make-the fork's condition is similar to the other tubes so check those insides then think about the chain stays and consider-at some point- getting the complete frame boiled out by a professional this need not be the first step- for now if pro boiling is out of reach, a thorough thinner-acetone-CHO-cleanout in a dry warm environment followed by thinned white rusto primer-2 coats-will save the frame for several years. using the linseed as a base is a tossup recommended for seriously pitted agricultural type FeO\ anyway-you need to take it apart, clean, regrease and place new bearings into the mechanism, nhow not later so gfet a strong light and inspect the tubes
went to lunch and remembered- cold galvinizing with linseed on unbrushed rusty surfaces eventually produces a lumpy surface with cracks, cracks leak moisture and oxygen and that's square one if the area coated is unseen. this is old information and current products may have solved the problem. a solution would be a hi tech epoxy-flexable and adherent.
