What is a good clear steel coating?

[Alison]

I welded together some mild steel frames for a friend of mine, and am wondering what are some good ideas to clear coat the steel with? I have used a product supposedly for use on steel if inside (ZIM), but it is water based and creates small rust "blooms" just by being applied. I've used cheap spray on clear coats, but they seem to only help so much. I can't afford fancy and expensive powder coats, and I am looking for something fairly accessible and direct.

Any ideas?

[Araich]

Hi Alison, try a product called Penetrol. It is a clear oil based paint additive that has extremely high penetrating qualitites - pushing out the air and moisture from the pores in the steel which seed rust. You'll need to give the work several coats, the more the merrier, and ultimately rust will find a way under... Just the same as powder coating.
That said, in my experience it is the best coating of them all, and it is cheap.
If it is a complex shape, with hidden seams and pockets, I recommend using a diluted mixture (with turps) and drowning the work as the first coat.
Also, cleaning off the work first with thinners or meths seems to help.

You can buy the stuff (or similar) at any-old hardware store. Best of luck.

[ironman]

Hi, As far as clearcoating goes, I use a wire cup brush on my grinder and get off as much of the loose rust scale that I can. Then I clearcoat with automotive clearcoat using a spray gun. It's not cheap but seems to hold up pretty well. The environment will wreck havoc over time with ANY finish but auto paint products last a long time. I have since gone over to stainless steel and cor-ten steel and although expensive they don't need anything else done to them, as far as I know.

[steponmebbbboom]

VHT Urethane clear is good. It's available at auto paint stores. Clearcoating bare steel is tough if you want to retain the look of bare metal with no patina. It will require maintenance if the work is installed outdoors. You can use a matting agent if you don't want any shine.

[bradjam]

Allison,
I know some pros using Penetrol but there work is considered indoors only. It does create a very nice finish though.

As stated by others wire brushing and a solvent to clean prior to coating is always good. There are also some metal conditioning products that nuetralize the metal prior to coating but can have there own look by altering the natural steel appearance.

I've been using a product called "Permalac" which can be bought in a spray can or in a paintable liquid. It's quite toxic so protect yourself but then most of these products are high in solvents when oil base.

I've tried quite a few products both watrer base and oil and find Permalac to be very durable even outdoors. The only pitfall is it is Satin /Gloss.

You can buy it here http://www.sculptnouveau.com

Good Luck!

[evaldart]

Penetrol is very good; better than urethanes, epoxies, laquers and acrylics, especially over rusted steel. I have pieces outside that have retained their rubbery gloss for a few years and going. I do anticipate, as with ANY clear coat, a restoration down the road. But its quick and easy. Keep your steel thick, your coating clear and use the rust as aggregate...nothing looks better.

[JamesONeil]

I have also used Permalac. As mentioned it uses some nasty solvents, just get plenty of fresh air while spraying. ArtChemicals.com also sells it, or just go direct to the Permalac site.

The Permalac website http://www.permalac.com/ offers some testimony to 10 year durability, etc. and ArtChemicals also offers some testimony to durability.

I have also used the Krylon/RustOleum clear coats and they appear to work well also. I couldn't get Permalac in time for a project.

[nep75]

I also agree with Permalac as it has UV protectors in it. A good way to prep the surface of the steel is to clean it as well as possible. After you get your patina (if you are applying a patina) on and where you want it, brush or spray acetone (definately wear appropriate safety gear, a resperator and gloves outside) on the whole piece. When this evaporates, it will insure that there is no moisture on the steel to get stuck between the coating and the surface. It's not cheap but works well if applied correctly.
Niki

[Mr. Malloy]

I like the thread, About the acetone? I thought it was cheap? I have not used it though. Do you just need to coat the piece? if so, can I brush it on? I wonder. and that can work right on top of the "rusty" finnish?