How to paint steel fabricated stuff

[jrcampbe]

Hey guys,

I took a welding class and got myself set up with an oxy fuel (mostly for mechanic work) and a MIG welder (Miller 211). I've been practicing and can make some decent beads.

Now I'm ready to start making all the stuff I want to make. Starting with something like the Steveo bench. Melanie also wants a cooking bench for which I intend to use an IKEA counter top on a welded frame similar, but lighter, than the Steveo bench frame.

So assuming I can actually make the thing, which I believe I can, I'm wondering the best way to paint it. I know all the mill oil needs to be cleaned off the steel, then it needs to be primed and painted some how.

What's the best way to handle these steps (clean, prime, paint), assuming a home garage without automotive painting equipment? Though I have a good air setup and would buy a paint gun if it is indispensable.

Thanks everyone. Big learning curve!

Jim

 

[ZRX61]

Just send it out for powdercoat

 

[rockwithjason]

For most projects a good cleaning with solvent will do. Follow up with self etching primer and paint. For automotive level finnishes you will need much more equipment and knowledge

 

[csp]

You can paint over the mill scale.

Clean all oils with mineral spirits or acetone or other solvent of your choice. Paint with spray bomb can (including a self-etching primer first) until you have a paint gun.

 

[Sea_Chicken1]

Depends on the use. Ideally powder-coat would be the best. I have gotten good results with epoxy appliance paint on parts that get allot of wear. Make sure that you clean whatever you make really good and prime it as well.

 

[Ole Slewfoot]

Sometimes its nice to start with some weld through primer in a spray can.

 

[APEowner]

Don't overlook good old brush on Rustolium. It's easy to apply, flows out nicely, doesn't require any special equipment and holds up surprisingly well.

 

[astroracer]

Get yourself some maroon ScotchBrite. Clean up the bare metal with the ScotchBrite and some mineral spirits. The ScotchBrite will leave a decent tooth for primer.
Rustoleum out of a rattle can will work fine. If you are painting it a dark color. use a dark primer. A light color, use a gray primer.
I have found Rustoleum's Hammered paint to be very tough once it's sprayed and had time to set.
If you warm the rattle cans in hot water before spraying the paint will flow much better.
Mark

 

[sberry]

I do some cleaning before its assembled, did a job a while back where the steel was all primed, tapes where it was to be welded, cleaned some and painted after.
A lot of stuff used indoors can be done simple though, agree with some brush on, get some sponge brushes.

 

[matt_i]

I think you will want to use a combination of flap discs and knotted wire brushes to dispel any weld flash and smooth/roundover corners and edges. A file will work where there's "finer" work to do.

I like to use non chlorinated brake cleaner and "lintless" towels to give the metal surface a good wipedown before painting, and repeat until the surface comes clean. Solvent evaporates quickly.

I sort of hate using rattle cans, the paint drys soooo slowly, although one can't beat the convenience. I usually try to set it out in the sun for a day, weather permitting, to let the radiant heat help bake out the long-chain VOCs. If brush painting, I use cheap brushes and toss them after use, I don't bother to solvent-clean them.

 

[brownbagg]

rattle can from walmart

 

[Wanna Ride]

rattle can from walmart

^^This. Knock the scale off with a quick pass of the grinder with a flap disc, a quick wipe down with rubbing alcohol, a coat of rattle can primer, and rattle can of your preferred color, and it'll look great. Inexpensive, easy and makes for excellent results.

 

[theoldwizard1]

Cleaning is the most important step !

You can do a good job with spray cans, but READ THE LABEL ! Most spray cans will take 2 coats of primer to get complete coverage. Time between coats is important.

Finish coats may require as many as 3-4, but again, READ THE LABEL. Some say wait 10-15 minutes between coats, some say 30 minutes. If you wait overnight, you will likely have to sand.

 

[bjcouche]

I second the rattle can suggestion. If the color you want is available in a rattle can, then go that route. A couple tricks are to prime first, and also to apply several light coats instead of a couple heavy coats. If you try thicker coats, you'll end up with runs and paint that takes forever to dry. Also, keep in mind that glossy finish paints seem to take much longer to dry. When applying the second, third, etc. coat, either wait the recomended time between coats or wait at least 24 hours. If you come back 2 hours later for the second coat, you will either get orange peel, or the second coat will never dry. Lastly, if you can paint the part lying flat, then there is less chance of runs. This isn't always possible, but for things like a door, instead of painting it hanging in the doorway, take it down and lay it flat on some sawhorses to paint it.

Brian

 

[PugetDude]

Anything but Rustoleum spray cans! Although readily available at any big-box store, it takes forever to dry, has an unrealistic recoat window, and chips easily. Tractor/implement paint goes on well and holds up much better.

Rustoleum in a can seems to work OK, but Hammerite is a better choice IMO.

 

[Wanna Ride]

I know this is going to sound crazy, but the best results I've had, with little to no effort or hassle, has always been the cheapest rattle cans. Seems like the expensive stuff is finicky, and always takes MUCH longer to dry. Almost everything I've ever built, has been painted with cheap rattle cans, and lasted as long as, and held up as good as (if not better) than every other paint, sprayed, rolled or brushed.

Powdercoat is anther story all together, but costs lots more. I've used that on a few specific parts that required it, but so far, cheap rattle cans have been the best route for many reasons.

 

[Ign]

I clean with non-chlor brakleen and rattle can Rustoleum. I replace the stupid nozzles w adapters from Art Primo (just a few bucks) and I'm sailing. I prefer Rustoleum Professional.

DO NOT remove the mill scale unless you're prepared to then hit it with something like a Velcro-backed ScotchBrite pad. The minuscule gouges and waves left by a standard grinding wheel will require an extra 2-3 coats to cover up unless you "polish" it after grinding.

Powdercoat is fine but A) costs more and B) is not really at all user-serviceable for touch-up down the road. I prefer rattle cans in readily available colors for future repairs.

All of this applies only to basic weldments and utility-based pieces. If you're looking for automotive, show quality or immaculate finish, disregard all the above.

 

[maxpower_hd]

I use acetone mostly for cleaning metal although many solvents work well. I just feel acetone does the best job of removing the oils...and I like the smell.

I have used brush on rustoleum and it works well. You can thin it and spray it from a gun too. But I do like the more expensive ones better. I have done a couple of truck frames with POR 15 and it works really well. It is thick and takes time to dry.

In a can I really like the implement paint from Tractor Supply. A guy at work turned me on to it and it is good stuff. It is thicker than any other spray can paint I have used.

 

[jimgood]

One thing I'll add is that I prep the tubes BEFORE I weld them. In my opinion, it's easier to run the angle grinder with a scuff pad over a straight tube than to try to do that after you've assembled a structure where you have to get into corners, inside and underneath.

After I assemble (weld) something together, then I just hit the welds with a wire brush then go over everything with dedegreaser (acetone). I usually brush or roll on my paint. I hate spraying and avoid it as much as I can.

 

[A**holes Garage]

I've always painted over the mill scale with a rattle can or had items powder coated.
I'm doing my first large project that requires the steel to have a chemically produced faux patina. I'm removing the mill scale with muratic acid to prep for the chemical patina treatment. Acid takes the mill scale right off in mutes, but once rinsed, it starts rusting immediately.

 

[theoldwizard1]

I have done a couple of truck frames with POR 15 and it works really well. It is thick and takes time to dry.

I have heard that you should NOT use POR15 on new metal. The steel needs to be "weathered" in order to have a good "tooth" for the POR15 to hold on to,

In a can I really like the implement paint from Tractor Supply. A guy at work turned me on to it and it is good stuff. It is thicker than any other spray can paint I have used.

There are several different brands of "implement" paint out there. All have gotten good reviews (assuming proper prep and priming). If you are going to use a spray gun, consider adding some enamel hardener. It will make that stuff almost as tough as epoxy paint !

 

[Farrier]

I use acetone mostly for cleaning metal although many solvents work well. I just feel acetone does the best job of removing the oils...and I like the smell.

I 2nd acetone. Cut all pieces first, de-bur and degrease and weld like an animal.

 

[Flail]

Flap wheel to knock the bird turds and sharp edges off.
Acetone to clean. Mineral spirits takes too long to dry and may stink.
Add Valspar enamel hardener to Rustoleum and it will dry in a few hours instead of days and will be tougher than plain Rustoleum.

When I'm working on a big project I will often first clean the metal outdoors and then prime it.
I then cut to size and flap wheel the areas to be welded areas. When done welding reprime the welds. Why? The local steel yard has a really oily/messy/stinky and black coating that gets on your hands and clothes when handling it. By cleaning and priming it first I don't have to be in rubber gloves all day and then hear my wife ***** about my clothes ruining the washing machine and stinking up the house because of the oil from the metal

 

[lukedwag]

Rustoleum is fairly low grade finish material. It's gloss retention and chalking are the biggest problems over time. PPG makes some great products depending on application. I really like Pitt guard and Pitt Thane ultra products

 

[Joemctag]

Usually, only tube has oil. Angle and flat bar just the black dust from rolling. Remove oil with newspaper or paper towel and solvent (thinner is fine)BEFORE fabricating. Doesn’t have to be totally oil-free. Primer will stick ( Don’t use latex primer on steel, except galvanized where you’re supposed to ). It’s a lot easier to clean a whole length. If the item is going outdoors, I get primer in all the corners with a brush first. Spray doesn’t want to go into corners and crevices. Outdoors, those places will “bleed” rust over time. White primer under light and bright colors will help them look good with fewer coats.

 

[Joemctag]

A 4” roller ( not foam ) can be a great way to put a good coat onto steel. An additive like Penetrol or equivalent from a paint store will make the paint really smooth. It covers less well, though. Hardeners are worth trying too because alkyd paint can take a long tim to r ally harden.”

 

[Kevin54]

Someone opened up a Zombie thread